5 Ways To Fight Hunger Cravings

Why the hell can we not stay full during the day? I talk to and overhear a lot of conversations that involve being hungry from busy students or professionals who are at work many hours of the day. What can they do to ensure they stay away from the vending machines at work or on campus or the shitty dining hall/cafeteria food? There’s a few things you can start doing to stave off those hunger cravings.

1: Plan Your Food, Foo

I can’t stress enough how valuable it is to plan your meals ahead of time. Bodybuilders and gym bros/bras have it right with bringing tupperwares of food with them. Now, it isn’t necessary to bring 50 meals with you for an afternoon of work. One large meal should be fine. Take some time either the night before or a few days before to prepare food for the next day or upcoming week.

When you’re prepping, make sure you’re aware of the shelf-life of the food you’re preparing. Chicken is only good for a few days (I never personally go past 3 days) after cooking. Rice and beans last a bit longer, so those are good options.  This link shows a great chart for a wide assortment of foods in terms of their storage life fresh, frozen, cooked, etc. Refer to that link if you’re unsure!

2: A Balanced Meal is King

Having a good mix of protein, carbs, and fat in your meal(s) will provide the best bang for your buck. You get a whole mix of nutrients and can fight off cravings by planning smart! For example, having a carb source that is high in fiber (vegetables, legumes, whole grain bread, etc.) with plant protein or lean meat topped off with a quality fat like avocado (which also has fiber) or canola/olive oil will put you in a great position in terms of feeling full for a long time and getting a lot of nutrients in a short time.

Having a balanced meal also just looks better and tastes better from an aesthetics and palatability standpoint. Having different colors, textures, and tastes in the meal elevates the taste, which is so important. Try it for yourself, and you’ll see even just preparing the food gets you excited to eat it.

3: Fiber, dammit!

I will talk about fiber until the day I die. This is such an important nutrient not only for general health (it helps to lower the risk for heart disease, diabetes, and cancer¹), but it also helps to keep you full and satisfied! If you want to learn more about the intricacies of fiber and why it helps you stay full, read my original post about fiber here.

Fiber is a pretty simply nutrient you can start including in your diet right now. If you’re prepping your food already, you can often exchange the carb sources in the meal for a whole grain or higher fiber option. For example, if you made a sandwich, shoot for the 100% whole grain bread. There’s a difference between 100% whole grain and 12-grain products. 12-grain products are often a hybrid between white bread and whole grain. If whole grain, wheat, etc. is available, go for that for fullness. If not, 12-grain isn’t a bad option.

Fiber is also found in fruits and veggies (why do you think we’re always encouraging you to eat them??). In the position stand by the Academy of Nutrition and Dietetics, they have a great chart outlining a whole bunch of common foods that contain fiber. It’s too long for me to embed here, otherwise I would. Check it out for yourself.

If you’re going out with friends or colleagues, look for options with whole grain bread, fruit, or a side of veggies to increase the fiber and satiety you get from that meal. You can also typically find fiber in protein bars like Quest bars or Complete Cookies. It’s very easy now to get fiber in your diet!

4: Protein!!!!

Protein isn’t just for people who go to the gym or the bro who downs a gallon of protein shake. Protein is known as the most satiating macronutrient compared with carbs and fat². Having high protein meals will absolutely help with feelings of fullness and feeling and staying full between meals. You can even double dip and eat foods that are high in protein AND fiber! Then you’re really winning! For example, legumes (beans, lentils, peas, soybeans, etc.) are high in fiber and contain a good amount of protein as well.

Adding protein to your meals (while minimizing the amount of fat that comes from the protein) will keep cravings at bay all day (See what I did there?).

5: Don’t Be Afraid of a Big Meal

Just because a meal is large and may contain a lot of calories (yes, “healthy” food can have a lot of calories) does not mean in any way, shape or form, that is going to make you fat or that it’s “unhealthy”. As a species, we require calories to survive and thrive. Unfortunately, we can’t always eat whenever we freely want to. This should not deter you from eating a bird’s portion when you do get the chance to eat because you’r afraid of gaining weight. If you haven’t eaten all day, chances are you can have a hefty meal and be fine.

Plus, if you’re following these guidelines when having that one meal (balanced, has fiber and protein, etc.), then you may not even eat it all because it will fill you up before you’re finished! My own meals fill up a medium-sized tupperware up to the lid, but I’m okay with it because I know to reach my goals that I need to eat! Food is your friend, let it help you!

What have you done to fight cravings throughout the day? Share below and help someone else! Thanks for reading!

References:

¹Dahl, W., & Stewart, M. (2015). Position of the Academy of Nutrition and Dietetics: Health Implications of Dietary Fiber. 115(11), 1861.

²Gerstein, Woodward-Lopez, Evans, Kelsey, & Drewnowski. (2004). Clarifying concepts about macronutrients’ effects on satiation and satiety. Journal of the American Dietetic Association, 104(7), 1151-1153.

Low Fat, Low Carb-Either Still Works: Media Misses The Mark Again

Hey everyone, Michael here. This is the first article on the blog from my friend Dr. Chris Berger. He’s an exercise physiologist and university professor, so he has a lot of good information to share. I hope you enjoy!

Admit it – You’ve had it with the latest studies telling you what to do.  I know I have.  As a doctor of my profession, high-quality data are the lifeblood of what I do.  I carefully structure my research and the classes that I teach on the basis of the best science out there.  But even us PhDs have to roll our eyes occasionally at what gets published and, more importantly, how the media run with it.

Consider, for example, the attention a new study got from the New York Times.  On Tuesday the 20th of February, the Times published a piece titled, “The Key to Weight Loss Is Diet Quality, Not Quantity, a New Study Finds”.  Alright.  Let’s break this down shall we?  First, “weight loss” has no key.  Weight is the product of mass times gravity so, I suppose, you could go into orbit and be happy with your weight absent gravity but… I have some bad news for you – you’d still be FAT!  Next, the notion that something as complicated as body composition (and our very personal concepts of what is ideal) does not have a “key”.  Why do we keep thinking that celebrities have a “secret” or that there is some trick to having a healthy body composition?  Any rational expert in the health sciences will tell you that body composition is dynamic and that obesity is multifactorial.  We owe our percent body fat to a lot of things.  Have we engineered physical activity out of our lives? (Yes)  Are we readily exposed to high-calorie palatable foods?  (Yes)  Have we cut the hell out of PE in schools?  (Ask your kid about that one or…do you not want to interrupt his video game?)  My point is that when you see news of a study that concludes that it’s this – this one thing here everybody – that is making us fat, you need to be critical of the work.

Not surprisingly, this study cited by the Times was praised by an MD – a cardiologist to be exact.  Now don’t get me wrong, I respect physicians.  I just wish that they would respect me.  I have something they don’t have – a thorough understanding of how physical activity impacts body structure and function and the research skills to find out more.  And without them, one draws bone-headed conclusions.  Don’t believe me?  Repeating:  The Times published a piece titled, “The Key to Weight Loss Is Diet Quality, Not Quantity, a New Study Finds”.  Yet what the study ACTUALLY concluded was the following (and I’m copying this verbatim):

In this 12-month weight loss diet study, there was no significant difference in weight change between a healthy low-fat diet vs a healthy low-carbohydrate diet, and neither genotype pattern nor baseline insulin secretion was associated with the dietary effects on weight loss. In the context of these 2 common weight loss diet approaches, neither of the 2 hypothesized predisposing factors was helpful in identifying which diet was better for whom.

But do you even need a PhD or an MD to translate this for you?  THEY FOUND NO DIFFERENCE.

Americans are fat for a lot of reasons but I’d like it to be the case that when we make personal efforts to improve our health, we do so with good information.  We rely on the news media to so inform us.  Instead, what we often have is a rush to headlines and an “endorsement” by somebody who seems credible.  Clickbait.  Bear this in mind for the next time you hear the “breaking news” on something in the health sciences.  Educate yourself on how to read and be critical of studies using the attached guide from the International Food Information Council Foundation and be careful not to jump to conclusions.  There is a lot to know in the health sciences and it’s not likely that one research paper will tell you it all.

Christopher Berger, PhD, ACSM EP-C, CSCS

References:

Gardner CD et al.  Effect of Low-Fat vs Low-Carbohydrate Diet on 12-Month Weight Loss in Overweight Adults and the Association With Genotype Pattern or Insulin Secretion: The DIETFITS Randomized Clinical Trial. JAMA. 2018 Feb 20;319(7):667-679.

Fresh vs. Frozen (vs. Canned) Produce, Who Wins? Part 3: Canned

WE ARE BACK 

To finish up this monster of a blog post all about The Produce Wars. Which is better, and which is worse?? (SPOILER ALERT) Well, hopefully, by now you’ve seen that each type has its pros and cons, and that not one is better than the other, because each has its own way of processing, storage, cooking method, etc. that will help it retain nutrients or lose some in these processes. With that being said, let’s finish up by discussing canned produce and its trade-offs. We’ll wrap up with some application of where and how you can use this information.

Let’s go

Canned Produce

Processing

Here’s where canned produce can fall short pretty dramatically in terms of nutrient availability. For many canned products, they undergo “Thermal Processing” which simply means heating something to kill bacteria and other microorganisms. As we learned earlier, water-soluble vitamins such as C & B are very sensitive to heat, and are lost in this process.

For example, carrots and broccoli saw losses greater than 80% just from the canning process alone1. Interestingly, however, corn and beets saw very small changes when canned1, perhaps because they’re tougher on the exterior?

The B-vitamins appear to be all over the board in terms of how much of the nutrients are lost. Thiamin (B1) saw 25%-66% losses in spinach, while the same study saw no changes in the Thiamin content of tomatoes2. Honestly, the story seems pretty similar across the other B-vitamins. There was so much variability, that I’m not going to waste your time going into the details behind it all. You can read the review itself if you’re curious1. My takeaway for the B-vitmins since they’re so variable is to try to derive them from non-canned sources if you can since the losses appeared to be higher than the retention for most of the studies1. There’s a helpful chart that you can refer to that pretty much spells it out for you!

When turning to the fat-soluble vitamins, there is a different story. Vitamin A actually saw some increases in its concentration after the canning process! One study found increases ranging from 7%-50% in green beans, sweet potatoes, spinach, and collard greens3. But the picture isn’t perfect. In that same study, peaches showed a 50% drop along with a 13% decrease for vitamin A in tomatoes. Upon further reading of this review, one can see that the research about canning and vitamin A content is actually pretty fuzzy, consisting of studies on both sides4. My opinion on this would be to acquire your vitamin A from a variety of canned products if they’re your only option.

Not much research has been conducted on vitamin E and canned foods because the foods with the highest concentration of the vitamin are not typically canned or fruits/veggies; however, some studies have shown large increases after processing in tomatoes5. It appears as though heat, similar with vitamin A, activates the vitamin within the food and allows it to be extracted/consumed in a greater amount than in the raw form. This only occurs up to a certain extent. After being converted to tomato paste, some losses of vitamin E occurred5. Interestingly, the USDA reports that canned products, when compared with their fresh or frozen alternative, have higher amounts of vitamin E4.

Here is where things get kinda interesting.  The amount of minerals in canned products can actually get increased during the canning process5. When canning, water is often added to preserve the food longer or create a syrup base to the food. Depending on the geographical processing location, the water may actually add minerals such as potassium and calcium5. With this, however, comes the enormous increase in sodium. That is my one caveat if you’re going to get canned, search for low sodium or salt-free options when available and financially feasible.

For fiber, the rule stays the same: physical preparation/removal is going to lower the fiber content. In foods such as tomatoes and asparagus, the researchers saw a 27% drop in fiber content; however, other foods, even after physical prep, did not see changes, largely due to the outer or thicker layers remaining intact2.

Storage

Moving on to storage of canned products, we start again with ascorbic acid (vitamin C). Pretty simple here, and, as you can imagine, not much losses are incurred after storing canned foods for a long time (18 months in these studies). Losses for vitamin C were no more than 15% for a variety of veggies1.

For the B-vitamins, there actually appears to be variety in losses depending on the food. Thiamin, riboflavin, and niacin, which are all B-vitamins, saw significant losses after 8 months in canned tomatoes6, but saw no changes in fiddlehead greens7. I had to google what fiddlehead greens are. I’m not sure we have those in the US or Arizona at least lol.

There were not a whole lot of studies that observed the effect of canned storage on vitamin A, but the few that did showed little to no change in the amount of the vitamin over time when in storage4.

One funny thing that happens with canned foods is that, depending on the material of the can, the food will experience increases or decreases in the amount of iron or copper. Steel-plated tin cans have been shown to increase the amount of iron in a food8. Other than that, other minerals are not really affected during storage8.

There wasn’t much to be said about fiber in canned foods, but the summary is that some foods like fiddlehead greens may experience a decrease as much as 25% if canned and stored for 10 months4.

Cooking

Since canned products are often already cooked, there are few additional losses from cooking for vitamin C, assuming that little if any water is added and the food is cooked only to get heated1.

Many of the studies that considered B-vitamin retention consistently showed that, while frozen and canned products may contain the same amounts of B-vitamins (even though they were low), both forms still have lower amounts than fresh counterparts1.

Vitamin A studies showed that cooked fresh carrots and other veggies had higher amounts than frozen and canned options, but all forms were still good sources of vitamin A1.

Unfortunately, there was not much to report about vitamin E except data from the USDA which showed that canned products compared to fresh and frozen had significantly lower amounts of the vitamin1.

The effects on mineral losses in canned goods was focused primarily on sodium losses. A 1975 study showed that if you rinse the canned food in water before cooking, you can reduce a significant amount of the sodium content by 23-45%9.

There were no mentions of fiber losses from canned products, but I imagine that it would be similar to cooking fresh or frozen foods since the main thing that affects fiber content is physical processing.

Takeaways

This is going to be a bit longer than my normal takeaway, as I’m going to wrap up this entire series, but I hope you have learned something from this small series of posts. The primary idea I wanted to communicate to you was that fruits, veggies, and other produce goods come in different shapes, sizes, and forms. Each form has its own pros and cons, and each contains more or less of certain nutrients than the other. Mainly, this set of posts was to relieve stress that some people feel when getting hung up about buying the fresh or frozen option. Either one is fine. The fact that you’re eating veggies is great, and be happy about that. With that, a quick summary of each option’s yays and nays:

Fresh produce often showed higher amounts of the nutrients, but would degrade significantly faster. Unless you’re going through your produce drawer every three days, I’d advise mixing it up a bit. Fresh produce can also cost more than the frozen or canned, which can be a barrier for many people. No one shouldn’t feel bad about buying cost-appropriate options, as they can contain similar or even more of certain nutrients.

Frozen and canned goods possess a lot of benefits just like fresh foods do. Obviously, they last longer and retain their nutrients for a longer period of time. Also, many food companies are now making strides in nutrient-dense frozen meals that taste freaking awesome! If you’re busy and on-the-go, frozen meals can be an awesome option for you.

Canned goods are great in that they are often enhanced with delicious flavors that would be a pain in the ass to make your own. Or, they are already cooked, and all you have to do is heat them up and you have food! My advice with canned foods is drain the sodium before cooking by rinsing it for a few seconds.

I also think it’s important to note that there were some limitations in the review and research I used, so these data are not going to 100% accurate and correct all the time 24/7. The studies varied greatly on how they measured losses and retention-mostly on a dry weight vs. wet weight basis-and the years that they were published. As time goes on, research methods improve and may even invalidate some older studies, so these papers are not without their faults, but they still provide some valuable information about how you can make smarter decisions about what you eat!

In conclusion, fresh, frozen, and canned foods are all great and can be part of a healthy diet. Learn to experiment with all the options an variety you’re given, and you’ll come across some pretty cool stuff! Let me know some canned or frozen recipes or foods you found that changed your life! Thanks for reading!

References

1Rickman, J., Barrett, D., & Bruhn, C. (2007). Nutritional comparison of fresh, frozen and canned fruits and vegetables. Part 1. Vitamins C and B and phenolic compounds. Journal of the Science of Food and Agriculture, 87(6), 930-944.

22Martin-Belloso O and Llanos-Barriobero EProximate composition, minerals and vitamins in selected canned vegetablesEur Food Res Technol 212182187(2001).

33Lessin WJCatigani GL and Schwartz SJQuantification of cistrans isomers of provitamin A carotenoids in fresh and processed fruits and vegetablesJ Agric Food Chem 4537283732 (1997).

4Rickman, J., Bruhn, C., & Barrett, D. (2007). Nutritional comparison of fresh, frozen, and canned fruits and vegetables II. Vitamin A and carotenoids, vitamin E, minerals and fiber. Journal of the Science of Food and Agriculture, 87(7), 1185-1196.

5Abushita AADaood HGand Biacs PAChange in carotenoids and antioxidant vitamins in tomato as a function of varietal and technological factorsJ Agric Food Chem4820752081 (2000).

6Saccani GTrifiró ACortesi AGherardi SZanotti Aand Montanari AEffects of production technology and storage conditions on the content of water-soluble vitamins in tomato pureesInd Conserve 76107118 (2001).

7Bushway AASerreze DVMcGann DFTrue RHWork TM and Bushway RJEffect of processing method and storage time on the nutrient composition of fiddlehead greensJ Food Sci 5014911492, 1516 (1985).

8Elkins ERNutrient content of raw and canned green beans, peaches, and sweet potatoesFood Technol 336670 (1979).

9Sinar LJ and Mason MSodium in four canned vegetablesJ Am Diet Assoc66155157 (1975).

Fresh vs. Frozen (vs. Canned) Produce, Who Wins? Part 2: Frozen

Welcome back! We’re continuing our discussion on whether you should eat fresh, frozen, or canned fruits/veggies. So far, we’ve seen the pros and cons of fresh produce: High in nutrient density, but loses its nutrients quickly if stored for a few days! How can we combat that?? Hmmm…..??? Got it! Freeze the colorful bastards! Yes! I’m saying freeze your produce or buy frozen if you know you store food for a while. Also, you may get more nutrients from doing this. Let’s look at what the data says about frozen produce in comparison to other methods!

Frozen Produce

Processing:

Last post, I did not include processing as a means of loss because fresh fruits/veggies don’t really experience much processing that could affect nutrient availability. Time was a primary factor in losses from fresh produce. I include it here because the freezing process can have an effect on the nutrients in food.

Processing for produce involves cooking the food then quickly freezing it. This is typically accomplished through blanching. This process involves boiling the food for a very short period of time, enough to cook it. Then, the food is thrown in cold water or an ice bath to freeze! This process can yield some losses in nutrients.

For example, one study found a 63% loss of Vitamin C in green peas just from freezing the food1. Numerous studies were compared to examine the loss of Vitamin C during the blanching and freezing process. Across the board, there was a lot of variance (From 17%-63% losses). Alternatively, while broccoli and spinach showed the greatest losses, asparagus appeared to be the hardiest vegetable, as Vitamin C was shown to retain 90% of its concentration after freezing2. Most of the vegetables reviewed saw fewer losses of ascorbic acid to freezing than canning, with some veggies losing as much as 90% of their Vitamin C just from the canning process2.

Losses of B-vitamins are similar to Vitamin C in that they vary greatly between studies, but the percentages were, on average, lower in terms of percent lost to freezing. Freezing was similarly a more efficient process than canning to preserve B-vitamins2.

For the fat-soluble Vitamin A (specifically beta-carotene), their does not appear to be a major change in loss between canning and freezing; they both appear to lose about the same amount2. Vitamin A was shown, as seen through multiple studies, to have losses ranging from 5%-48%2. The authors of the review made an interesting point that the typical American’s main source of Vitamin A is through lycopene in tomatoes, and these are not normally frozen2, so this may not be a super important point if most of our intake is from tomatoes anyway!

Not much is mentioned of Vitamin E, but it appears that canning may produce a slightly greater amount of the vitamin than fresh and frozen counterparts2.

In terms of minerals, fresh, frozen, and canned veggies all were neck-and-neck. One food would have more calcium when canned, then the next would have more calcium when fresh, and so on and so on. Just from my judgement, with the exception of sodium, it seemed as though fresh and frozen produce showed, on average, higher amounts of the minerals when compared to canned counterparts3.

For fiber and processing, the only time fiber was lost was when some of the fibrous portions of the food were physically removed. There appears to be nothing about canning or freezing the affects fiber if the food is left intact2.

Storage:

As one can imagine, frozen produce does much better than fresh in terms of nutrient retention during storage. Regarding Vitamin C, after one year of storage, one study saw an average decrease of 20%-50% for food such as broccoli and spinach4 whereas fresh foods can see those losses or greater in as little as 24 hours5!

Unfortunately, the data is pretty inconclusive about B-vitamin losses, so I’m not going to include it here.

In regards to Vitamin A, some studies say a small increase in Vitamin A concentration after storage6 while others saw no change or decreases after storage for a period of time7.

Data from the USDA suggest that some foods like tomatoes and sweet potatoes contain higher levels of Vitamin E when canned compared to their fresh and frozen equivalents; however, spinach and asparagus showed higher levels when fresh or frozen8. Basically, the results are inconclusive, there is no clear winner for this category.

As mentioned in the last post, fiber and minerals are much hardier components of food than the other vitamins, so losses from them are very minimal, including when they are frozen for months on end8.

Cooking:

Home-cooking foods can have a significant effect on nutrient losses. Generally, when heat is applied, some losses will occur, especially in the water-soluble vitamins.

When compared with canned and fresh produce, frozen held its own with fresh foods for Vitamin C retention-throughout processing, storage, and canning-being very similar in nutrient quality compared across a range of foods. Canned produce fell short, withstanding significant losses throughout the processing, storage and cooking steps2.

For the B-vitamins, it has been seen that Thiamin, a vitamin important for cell metabolism and growth9, can witness small or significant losses during the cooking process (11%-66% loss of nutrient)10. From other studies, they showed that canned and frozen produce fell equally short to fresh foods after cooking for the B-vitamins11,12.

Vitamin A one again saw increases in availability after cooking. Some of the foods saw even greater percent changes when frozen than when cooked. For example, one study saw only a 5% increase in Vitamin A for carrots when fresh compared to a 21% increase when frozen13

Vitamin E in frozen foods was not really mentioned, so I will skip this portion.

When looking at the minerals sodium, calcium, and potassium, some interesting results were noticed. Across the board, concentrations of potassium and calcium were similar after cooking for fresh, frozen, and canned foods when testing green beans and peas12. One can assume that canned foods will have a higher amount of sodium due to processing12. What this tells us is that generally, produce will have similar amounts of the beneficial minerals. If you’re watching sodium, opt for either non-canned options or those that are sodium-free/no salt added. One caveat, this study only looked at those two vegetables. The results may be different when looking at fruits and vegetables. My personal opinion is that it may not be too different simply because minerals are more resistant to heat and cooking than the vitamins.

In reference to the last post, fiber isn’t really lost from the cooking process unless you physically remove the tough, fibrous, parts of food. Researchers went to the grocery store and purchased some food off the shelf to observe its fiber content and compare fresh, frozen, and canned foods. What they found was that cooked frozen and cooked canned green beans and peas had 25%-35% greater amounts of fiber than the cooked fresh counterpart12.

Keep in mind, this is one grocery trip they took. Fiber content may vary between batches, but it is an interesting point because I think that most people would think that the fresh food will always have more nutrients, which, as we just saw, is not always the case.

Phew, this was a longer post than most of the others. My b. But there was a lot to cover! I will be going over specifically canned produce next week, so look forward to that! Here are my takeaways!

Takeaways

  • Frozen foods last significantly longer than fresh foods. If you plan on having food for a long time or like to stockpile for nuclear war for some weird reason, go frozen.
    • In many cases, frozen foods have similar nutrient amounts to fresh.
  • In addition, frozen foods take a long time on average to lose a lot of their nutrients, so store those babies for a while, you’ll be good!
  • Frozen foods (including meals) are a quick and easy way to make a meal, since the prep work is usually done.
  • Try limiting the time you heat/cook any kind of produce. The longer it stays in hear or water, the greater chance you will lose nutrients
    • On the other hand, don’t drive yourself nuts and only eat raw foods, that’s not the way either. If you can limit water and heat use and still get the same product, great. If not, no biggie, enjoy your damn food.

 

I hope you found this article useful. Let me know how use frozen foods in your meals/meal planning, I’m always looking for ideas!

References

1Fellers CR and Stepat WEffect of shipping, freezing and canning on the ascorbic acid (vitamin C) content of peasProc Am Soc Hort Sci 32627633(1935).

2Rickman, J., Barrett, D., & Bruhn, C. (2007). Nutritional comparison of fresh, frozen and canned fruits and vegetables. Part 1. Vitamins C and B and phenolic compounds. Journal of the Science of Food and Agriculture, 87(6), 930-944.

3Makhlouf JZee JTremblay NBelanger AMichaud MH and Gosselin ASome nutritional characteristics of beans, sweet corn and peas (raw, canned and frozen) produced in the province of QuebecFood Res Int 28253259 (1995)

4Hunter KJ and Fletcher JMThe antioxidant activity and composition of fresh, frozen, jarred and canned vegetablesInnov Food Sci Emerg Technol 3399406(2002).

5Favell DJA comparison of the vitamin C content of fresh and frozen vegetablesFood Chem 625964 (1998).

6Salunkhe DKBolin HR and Reddy NRChemical composition and nutritional quality, in Storage, Processing, and Nutritional Quality of Fruits and Vegetables. Vol. 2: Processed Fruits and Vegetables. CRC Press, Boca Raton, FL, pp. 115145 (1991).

7Elkins ERNutrient content of raw and canned green beans, peaches, and sweet potatoesFood Technol 336670 (1979).

8Rickman, J., Bruhn, C., & Barrett, D. (2007). Nutritional comparison of fresh, frozen, and canned fruits and vegetables II. Vitamin A and carotenoids, vitamin E, minerals and fiber. Journal of the Science of Food and Agriculture, 87(7), 1185-1196.

9Thiamin Fact Sheet From NIH

10Rumm-Kreuter D and Demmel IComparison of vitamin losses in vegetables due to various cooking methodsJ Nutr Sci Vitaminol 36S7S15(1990).

11Lisiewska ZKorus A and Kmiecik WChanges in the level of vitamin C, beta-carotene, thiamine, and riboflavin during preservation of immature grass pea (Lathyrus sativus L.) seedsEur Food Res Technol 215216220(2002).

12Wills RBEvans TJLim JSScriven FM and Greenfield HComposition of Australian foods. 25. Peas and beansFood Technol Aust 36512514 (1984).

13Howard LAWong ADPerry AK and Klein BPβ-Carotene and ascorbic acid retention in fresh and processed vegetablesJ Food Sci 64929936(1999).

Fresh vs. Frozen (vs. Canned) Produce, Who Wins? Part 1: Fresh

People are always going to argue over the stuff that is 5% of the equation while ignoring the actually important 95%. This debate between fresh, frozen, and canned produce is part of that 5%. Why? Because for the most part, a vegetable is a vegetable is a vegetable. While we may want to get all of our nutrition from fresh foods and be #healthy, that’s not always financially, practically, or geographically possible. Luckily, with the technological advancements in food processing (yes, I think processing can be a good thing), we are able to preserve foods and acquire foods we would never have gotten a chance to eat given our location. These developments have not come without criticism, however.

Many will claim that canned or frozen fruits and vegetables are not “as healthy” as their fresh counterpart. First off, please define healthy. You can’t measure something with healthy. “Oh, this food has 5 health”, this isn’t a freaking video game. Talk about nutrient density; that’s a good way to measure the healthfulness of a food. Nutrient density refers to the quantity and variety of nutrients (vitamins, minerals, fiber content, etc.) that are in a food. Obviously, fruits and veggies are extremely nutrient dense; but do they contain the same amount and types of nutrients across the board from fresh to frozen to canned? That’s the topic of discussion for today.

The Research

In 2007, there was a great literature review published in the Journal of the Science of Food and Agriculture that compiled a lot of the research conducted in this area over the last several decades from UC Davis1. This review was broken up into 2 main sections: Water-soluble & lipid-soluble. The difference here is that some nutrients dissolve in water while others dissolve in lipids (or fats). The properties of these nutrients change depending on their solubility. For example, water-soluble vitamins (C & B) are very susceptible to destruction from high temperatures while lipid-soluble vitamins (A, D, E, K) can tolerant high temperatures and still remain in food.

Fresh Produce

Storage:

While it may come as no surprise that fresh produce was shown to have greater amounts of nutrients than frozen or canned, it may be interesting to know that fresh vegetables also degrade the quickest in terms of nutrient availability2. In one study, researchers found 56-100% decreases in Vitamin C content depending on the food item being tested. This was after storing the food at room temperature for 7 days3. Keep in mind, Vitamin C is a very unstable nutrient, so it’s sensitive and will be degraded the quickest of any nutrient, but for water-soluble vitamins, it’s a good estimation. Vitamin B losses were also found during storage, but not as dramatic as Vitamin C1.

Lipid-soluble vitamins had a different story. Vitamin A, in some cases, actually saw an increase in availability after a few days. This was seen in carrots refrigerated after 14 days4. Simultaneously, green beans experienced a small 10% decrease during refrigeration from 16 days4.

In part 2 of the review, minerals and fiber were tested in addition to lipid-soluble vitamins. What was seen there was that neither minerals or fiber saw significant losses during storage over many months1, although I wouldn’t eat anything considered fresh produce after a couple months…yikes.

Cooking:

As mentioned previously, water-soluble vitamins can be quickly destroyed if exposed to heat such as from cooking while lipid-soluble vitamins are more tolerant of supa hot fiya. One study tested the Vitamin C content of produce straight from the supermarket after cooking and found that some foods had higher Vit. C levels when fresh and cooked while others had more of the vitamin when coming from a can and then cooked3! In addition, ascorbic acid (Vitamin C) has been shown to see decreases after cooking as high as 55%5.

Thiamin, a B-Vitamin, has seen even greater losses from cooking at 66%6. The cooking method will also be significant factor for how much of the nutrient is lost to cooking; unfortunately, the authors did not specify which methods are better than others for nutrient retention, but my guess would have to be whichever method utilizes heat for the least amount of time would be best.

Lipid soluble Vitamin A had an interesting outcome when exposed to heat; it increased! One study found a 26% increase in the amount of Vitamin A available after cooking fresh broccoli7. Other studies did not find any increase but rather, a decrease1.

Minerals and their quantity in foods are able to be reduced from cooking by leaching into the water or cooking liquid out of the food1. If possible, use that cooking liquid again to get some of that nutrient back into a meal.

Fiber did not see any significant changes when exposed to heat1. The primary way that you’re going to lose fiber from cooking is through processes like peeling, juicing, and removing parts of fruits and vegetables1. For example, asparagus spears have the signature flower part to them and the annoying tough end to them. The reason why that end is tough is because it is loaded with cellulose/fiber. I’m not saying you need to eat all the hard parts of fruits and veggies, but save a little bit of it next time to get a little extra bit of fiber from your meal.

Takeaways

So far, we have only covered what the research has said about fresh fruits and vegetables, and haven’t really made a comparison with frozen and canned veggies. That will come next week when we talk about frozen produce and then the following week with canned products. For now, my takeaways are this:

  • Fresh is not always the best option especially if the produce is going to sit for a couple of days.
  • If possible, place fresh items in the fridge to slow the process of nutrient degradation
  • Cooking can contribute to the greatest loss of nutrients, but don’t eat everything raw either. My point is focus more so on getting fruits and vegetables in the first place. Then, worry about cooking methods and other things.

I hope you found this information useful to you. As I said above, We’ll start actually comparing the three forms next week, then you may be able to make better decisions about what you select at the grocery store! Leave me your comments with your thoughts!

References

1Rickman, J., Barrett, D., & Bruhn, C. (2007). Nutritional comparison of fresh, frozen and canned fruits and vegetables. Part 1. Vitamins C and B and phenolic compounds. Journal of the Science of Food and Agriculture, 87(6), 930-944.

2Favell DJ, A comparison of the vitamin C content of fresh and frozen vegetables. Food Chem 62:59–64 (1998).

3Hunter KJ and Fletcher JMThe antioxidant activity and composition of fresh, frozen, jarred and canned vegetablesInnov Food Sci Emerg Technol 3399406(2002).

4Howard LAWong ADPerry AK and Klein BPβ-Carotene and ascorbic acid retention in fresh and processed vegetablesJ Food Sci 64929936(1999).

5Goyal RKNutritive value of fruits, vegetables, and their products, in Postharvest Technology of Fruits and Vegetables, ed. by VermaLR and JoshiVK. Indus Publishing, New Delhi, pp. 337389 (2000).

6Rumm-Kreuter D and Demmel IComparison of vitamin losses in vegetables due to various cooking methodsJ Nutr Sci Vitaminol 36S7S15(1990).

7Lessin WJCatigani GL and Schwartz SJQuantification of cistrans isomers of provitamin A carotenoids in fresh and processed fruits and vegetablesJ Agric Food Chem 4537283732 (1997).

Basic Nutrition To Fuel Your Not-So-Basic Life Part 4: Fiber

Let me tell you something about fiber. When I first began my study of nutrition about 2 1/2 years ago, my very first nutrition professor was a fiber nerd! She loved fiber and talked to us about it like it was the best thing since sliced (whole grain) bread. Over time, I’ve realized why she was so passionate about this special type of carbohydrate.

It truly is awesome because it plays host to many benefits for our health; they’re vast and highly effective for our body’s proper functioning, so I wanted to take this time to define fiber, talk about why it’s so awesome, and provide some recommendations on how much should be consumed daily.

wtF is Fiber?

Hah. Get it?

Anyway, fiber, as mentioned above and in one of my original posts on my website about carbs, fiber is a type of carbohydrate. But, it’s very special. One reason is because fiber cannot be fully digested. Our bodies do not possess the proper enzymes and digestion systems to fully break it down. Why is it so hard for the body to break down? There’s a few reasons for that.

Fiber, on a very small-scale level is made up of A LOT of sugar molecules. Collectively, these bundles of sugar molecules bonded together are known as polysaccharides. Specifically, fiber is derived from cellulose¹. You may have heard of cellulose as being the cell walls of plant cells. FUN FACT.

Think of a long chain of beads like the picture below.pexels-photo-221550.jpegImagine that each bead represents one molecule of sugar. Now, imagine that this necklace is a chain of at least 1000 beads. That is fiber. Crazy, right? Our body will get fiber from food and there are a few interesting things that happen when we consume fibrous foods.

Function of Fiber

Primarily, our blood sugar begins to level off. When looking at graphs depicting levels of glucose in the blood, we’ll often see a huge spike in blood sugar levels when we eat sugary foods and things containing simple carbohydrates. Keep in mind simple carbs refer to small chains or single units of sugar that the body can quickly break apart and utilize for energy.

With fiber, we don’t see that spike. What we see is a gradual increase in blood sugar and a peak that doesn’t typically get as high as the peak would be from simple carbs. Additionally, blood sugar levels taper down at a slower rate than simple carb spikes. This has a lot of interesting health implications and is the fundamental idea behind diabetes and insulin resistance. I won’t go into how we develop Type 2 Diabetes in this post. I’ll probably talk about Diabeetus another time.

The slow and steady increase and decrease results from the body’s inability to digest fiber. Since we can’t break down fiber completely, it will sit in the gut and become “food” for our gut’s microbiome, a “community” of microorganisms that live inside us. While we don’t have the digestive system to break down fiber, the organisms living in our gut do to some extent. So they will partially break down fibers and convert them into fatty acids that we can break down and use for energy in a process called fermentation. This process takes some time, and we get fatty acids out of it, which take a while to break down in their selves, so this is what leads to that progressive increase and decrease in blood sugar. Pretty cool, right??

This is important for our health because small and slow increases in blood sugar are easier on our pancreas. Our pancreas secretes the hormone insulin that allows sugars to be shuttled into cells for energy. Slower and steadier increases mean less insulin has to be produced and secreted at any given time. Long-term production of insulin for large spikes is a risk factor for diabetes. For this reason, fiber has been noted as a component of the diet that can reduce the risk of Type 2 Diabetes².

Additionally, fiber can help lower your cholesterol and and risk for heart disease². The way this works is that as fiber travels through your digestive system, it will bind to cholesterols that are floating around in the blood, and, since fiber can’t be digested, it will be excreted with some cholesterol still bound to it. The cholesterol that is removed is the LDL or “bad” cholesterol. In effect, this excretion of LDL lowers our blood pressure and risk of heart-related diseases²! I think that’s cool. Maybe just me.

On a side note, fiber also keeps you fuller for a longer period of time than other carbohydrates. When consumed, fiber will slow the rate of digestion for the entire meal, keeping food in your stomach and fighting hunger for a longer period of time. So, if you know that you’re going to be out for a awhile, having a meal high in fiber can ensure that you will be full and energized throughout the day!

Sources of Fiber

But where do we get foods high in fiber? Glad you asked. It’s the typical “healthy” foods. I know, booooo; but, fruits, vegetables, legumes (think beans and peas), and whole grains are the most common sources. Ever have some fruit, then get a sense of fullness afterwards? Happens to me with bananas. That’s the fiber bruh!

Fruits/vegetables are the hallmark of any healthy balanced diet, and fiber is one reason why. Most fruits/veggies will have a fair amount of fiber per serving. Simply check the nutrition facts panel to see how much!

Legumes are things like beans, peas, lentils, etc. They’re often packed with fiber AND protein.  Double whammy!

When I mention “whole grains”, I’m talking about oatmeal, quinoa, brown rice, and whole grain products (bread, pastas, tortillas, etc.). For the last set of products, make sure the package says “whole grain” or “whole wheat” somewhere or on the ingredients label to ensure you’re getting the most fiber possible.

Recommendations

The American Dietetic Association is very credible source (obviously), and they recommend the following for individuals². You can find the source of this chart on the 2nd reference I have listed:

Capture

Of course, you’re not going to die if you don’t hit that fiber number, but it is a good idea to actively aim for around that number listed for your age group. Having a fruit/vegetable at every meal is an easy way to start that. Or just include one more veggie than you’re already having. Small steps is the way to big successes!

Last thing, MORE IS NOT BETTER. Jumping your fiber intake rapidly or getting too much fiber may make you constipated and/or cause a lot of wind-breaking (toots, farting, passing gas, pick your favorite). As you increase your intake, make sure you’re drinking more water too in order for the digestive system to continue moving. Too much fiber can back you up if water isn’t in check. Happy eating!

Takeways

  • Fiber is a type of carbohydrate that can’t be broken down in the body completely
  • Fiber has a lot of health benefits including lowering blood pressure and blood sugar²
  • Sources of fiber are the typical healthy foods like fruits, veggies, whole grains, and legumes
  • An adequate intake of fiber varies with age and sex, refer to the chart to see where you stack up!

Have questions?? Comment below about them or tell me your favorite ways to get fiber in your diet! Thanks of reading!

References

¹Dietary Polysaccharides (Article from Colorado State University)

²Position of the Academy of Nutrition and Dietetics: Health Implications of Dietary Fiber

 

I Made Some Mistakes On My Last Post, So I Fixed Them Here.

Hey y’all. Finals are done. Classes are out for a little while. I feel good. So good that I’ll be able to get back to writing every week!

Upon reading my last post about aerobic glycolysis, I noticed some issues with the article. There were some things that I either glossed over or need to revise, so this post serves as clarification on some of the hiccups in my last post. Nobody is perfect! Let’s wrap this ish’ up.

First off, I’d like to make the point clear that when you are training, energy systems don’t work like an on/off switch. For example, when you begin high intensity exercise, aerobic glycolysis is working along with the creatine phosphate and lactic acid systems. The difference is that most of your energy is obtained from the latter systems over the former at the beginning of your exercise/work that you’re doing; so energy acquired from aerobic systems will come into play later on as the length of exercise progresses, but the process has begun once you start training.

Next, I made a mistake regarding my explanation of aerobic glycolysis. Glycolysis is only part of the pie known as “Oxidative phosphorylation“. Specifically glycolysis refers to the breakdown of glucose for energy. As a reminder, we can get glucose from carbs or gluconeogenesis such as from lactate and glycerol from fats. This system (oxidative phosphorylation) is the sum of all aerobic reactions and pathways that create ATP; part of which being aerobic glycolysis. Proteins can also be used to produce small bits of ATP.

So during OP, energy may be derived from carbs, protein, and fats! Depending on the availability of nutrients will determine what your body goes for primarily. If you’re full of glucose or glycogen, then your body is going to use that because it’s the quickest and “costs” the least amount of energy to get energy. Your metabolism wants to save all the energy that it can for when it really matters.  Once glycogen stores are depleted, then fats and even proteins will take up a larger role.

Keep in mind that this system takes awhile to produce any energy, so it is not as though you can expect to lose weight just from depleting glycogen stores and relying on fat. You’ll eventually crash because the energy demand just for breathing and moving around could be greater than what can be produced. Simply, get off yo’ butt and move!

So it is a bit more complicated than just carbs and other things being converted into glucose then some magic happens and you have energy. But, that’s the exciting thing about learning! You can learn something new every day!

I hope this clarification of things helped the incomplete picture I painted previously. Maybe I just made it even more complicated. Either way, thanks for reading! Share this article and others to educate someone you know!

 

How Do We Acquire and Use Energy From Food? Part 2

Welcome back to our discussion of energy systems! I appreciate you coming back and your desire to learn! That’s the whole goal of this website: to learn ya’ somethin’! Upon reading a comment from the first post, a reader enlightened me on my neglect to go into detail about what ATP is or what is stands for. So, before I dive into the final energy system, aerobic glycolysis, I’m going to briefly talk about what ATP is! Let’s begin!

ATP Revisted

ATP stands for Adenosine TriPhosphate. This is the molecule our body synthesizes from all these different energy systems in order to make us move in all the ways that we do. Chemically, it is composed of a DNA molecule known as Adenine (in this case, adenosine), ribose, and phosphate groups.

Adenine is one of the four components that create DNA (Only four things known as nucleotides make up your entire DNA sequence! That’s amazing!). Adenine then binds (connects) to ribose, a sugar molecule. Finally, this sugar is bound to a chain of 3 molecules known as phosphate groups.

What makes ATP the OG energy molecule is those phosphate groups. These are known as “High-energy bonds” that, when broken off the ATP molecule, release A TON of energy that our muscles, cells, etc. use to do all the activities that we do.

When a phosphate group is removed from ATP, it becomes ADP (Adenosine DiPhosphate) and AMP (Adenosine MonoPhosphate) when two groups are removed. Here’s a nice visual from Khan Academy¹ to summarize what I mean by molecules, phosphate groups, etc.

Untitled design (8)

Phew. Okay. That covers ATP. Now! Onto the star of the metabolic show, aerobic glycolysis!

Aerobic Glycolysis

Why do I refer to this energy system as the star of the show? This is the system that not only provides the most energy, but it is also in use the most amount of time because typically, we aren’t jumping, sprinting, etc. We only do that for a relatively short period of time (even though it may feel like it never ends).

When we’re just walking, sitting, working, doing normal people stuff, we’re using this energy system. ADDITIONALLY, this is the primary energy system in use when we’re doing light to moderate-intensity exercise for a long period of time.

What’s the reason behind this? Well, for everyday stuff, we’re not in dire need of energy at that very moment like we may be if we’re sprinting away from a bear or angry girlfriend (which are equally dangerous).

Our bodies are built for survival. If it doesn’t need energy ASAP, it’s going to break it down slower but provide more of that energy on a per-cycle basis. What I mean by this is for each “cycle” completed of aerobic glycolysis, we get more energy molecules, meaning more energy for us! Woohoo!

After the lactic acid cycle is depleted/unable to work further, this system kicks in for the remainder of the exercise. Interestingly, long-distance runners can actually notice when their metabolism “switches” to aerobic glycolysis. It’s characterized by fatigue, tiredness, and a feeling of “hitting the wall”. They feel this way because energy isn’t being produced as quickly as we need it.

Also a fun fact, this system is aerobic which means it requires oxygen to start working. Ever notice that you start breathing more the longer you exercise?? You’re taking in that oxygen for a reason. Your body knows when it needs oxygen, and so your brain will tell you to breathe more to take in more oxygen! BOOM!

Why does it take so long to acquire this energy? Aerobic glycolysis relies on fat consumed in the diet or from body fat stores once dietary fat is consumed in order to synthesize glucose and/or ATP. I say ‘and/or’ because when we use fat as energy, it actually breaks into its two components (glycerol backbone and three fatty acid chains, refer to this article on fat for a refresher on the structure of fats).

Glycerol produces a small amount of glucose while the fatty acid chains cannot be converted into glucose; so they have their own metabolic pathway to produce ATP. Creating glucose from sources other than carbohydrate (protein, glycerol, lactate) is known as gluconeogenesis². We actually saw this during the lactic acid cycle! Lactate becomes glucose during the cycle!

Back to the question, fat, as an energy source takes a while because of those damn fatty acid chains. These chains are composed of a lot of carbon atoms that go through a lot (a lot!) of steps to become usable energy. This metabolic pathway is known as Beta-oxidation or fatty acid oxidation.

Why Does This Matter?

Well I’m not going to teach you something if it’s not important! Also, this information will be on the test next Thursday, so make sure you study it.

It’s important because if you do long-duration exercise, you will be using this energy system for most of the time. Additionally, this is the system in use most of the time throughout daily life!

Yeah. So what?

So what? SO WHAT?! This is a sign for you to see that dietary fat is not bad for you. It’s an energy source that is very important for prolonged energy production! Also, if you know that you’re going somewhere without food for a few hours, having fat in a meal prior will help you stay energized. ‘Energized’ does not equal ‘full’ though, keep that in mind. Combat stomach emptiness with fiber and protein!

But, if you need energy for a long time because you won’t get to eat, having some fat from nuts, peanut butter, oils, avocados, seeds, etc. will keep you moving forward! THAT’S why this is important, dammit.

Here is a helpful graph from Precision Nutrition³ to summarize what these last two posts were about. I encourage you to read that linked article too. It’s super informative!

As you can see, ATP stores in the muscle are used up almost instantly, followed by the ATP-PC system (Creatine Phosphate) in purple, then the lactic acid system in green after about 2 minutes. Finally, aerobic glycolysis kicks in for the remainder of the activity at the expense of exercise or activity performance aka “Hitting the wall”.

Image result for energy system use over time

Takeaways

  • ATP is the primary energy molecule made of adenosine, a sugar molecule, and phosphate groups
  • Aerobic glycolysis kicks in after the lactic acid system and continues pumping out energy for the duration of exercise or the activity being performed.
  • Dietary fat and body fat are the primary fuel sources for aerobic glycolysis (Does not mean you can sit on your ass and claim you’re burning body fat. It doesn’t work like that.
  • When used for energy, fat is broken into two components that enter two different metabolic pathways (gluconeogensis for glycerol and beta-oxidation for fatty acids)
  • If you can understand what system is used, you can better prepare meals for exercise or if you’re going to be out for the day!

Do you like posts like this where I explain nutrition science topics?? I love talking about this stuff because I feel that science needs to be communicated to the public more often and in a better way. That’s one purpose of this blog if you couldn’t tell by now! Let me know what you think in the comments! All feedback welcome! Thanks for reading!

References

¹Basic concepts in bioenergetics: phosphoryl group transfers and ATP hydrolysis

²Glucose Can Be Synthesized from Noncarbohydrate Precursors

³All About High Intensity Interval Training (HIIT)

How Do We Acquire and Use Energy From Food? Part 1

Ever think about how we, as the crazy people we are, get energy to do everyday stuff? Walk, run, jump, pick up kids, throw said kids because they’re annoying, even getting out of bed! Everything you do takes some bit of energy!

Where do we get that energy? Caffeine? Well, it may seem like it, but caffeine provides no ACTUAL energy. It’s just a stimulant that makes you FEEL energized. There’s a huge difference. We derive our energy from food in the form of calories from carbs, protein, and fat (and alcohol)!

But, let’s dig deeper..how exactly does your body break food down into components that it can use for energy? More importantly, why is this important? Well, if you know what and how your body fuels itself, you can provide it better fuel at better times to feel better, without stimulants!

So, what gives us the energy to live the awesome lives we live? These awesome things known as energy systems!

Energy systems are typically discussed in the context of exercise because that’s one of the few times that all the systems may be utilized during one time period. Typically, at rest, only one (aerobic glycolysis) is used; but, keep this in mind, whenever you’re doing strenuous work like moving or lifting heavy objects, the other sports-related systems may be in use.

There are a few ways our bodies use the different fuel sources. It all depends on the activity you’re doing and the amount of energy needed to perform that activity. Let’s begin by talking about what our body actually uses as energy. Hint: It’s not glucose (technically).

ATP

ATP is THE energy molecule. Whenever we’re doing literally anything, we’re using ATP. While we can acquire ATP from different forms (carbs, fat, protein, alcohol, etc.), it all funnels into ATP and some other secondary molecules. This happens because we have different systems in our bodies to break down the different macronutrients. With that in mind, let’s talk about what they are, when they’re used, and why this applies to you.

In part 1 of this series, I’ll talk about the exercise-focused energy system, Anaerobic Glycolysis; but remember, whenever you’re doing intense, strenuous work, these systems are working, so don’t skip this if you don’t exercise! Part 2 will cover the more general system known as Aerobic Glycolysis.

Anaerobic Glycolysis

To begin, we discuss Anaerobic Glycolysis. This refers to systems that generate energy WITHOUT the use of oxygen. Oxygen is the primary distinction between aerobic and anaerobic systems. Oxygen as a chemical has some interesting properties to it that allows us to create energy in different ways. The next two systems-Creatine Phosphate and Lactic Acid Cycle-do not need oxygen to create energy. Let’s begin!

Creatine Phosphate System

This is the very first system used when doing typically high-intensity exercise or activity. Anything from deadlifting 1000lbs to picking up some heavy furniture. This system is used for, as Deadpool says, MAXIMUM EFFORT. Creatine phosphate is made up of a few atoms-the things on the periodic table-to make a molecule (Chemistry 101 lesson right there, you’re welcome). This molecule, Creatine Phosphate, will donate some atoms to make ATP.

All of this occurs inside the muscle tissues, so energy is able to be generated very quickly, hence why it’s used first; but there is a very limited supply of creatine phosphate in muscles, so this system will deplete in a matter of seconds. So why does this matter? Well, if you’re an athlete, or someone who just likes to exercise (running, lifting, etc.), then this is what jumpstarts you whenever you start your exercise! If you’re going to sprint, that quick jolt of energy is this system at work. Knowing what systems are at work can allow you to better fuel up for training! Creatine is most commonly found in meats. Vegans and vegetarians may have to supplement it.

Creatine supplements work by flooding your muscles with creatine, thereby allowing this system to last longer than a few seconds and continue to produce energy quickly which can lead to better training sessions since your endurance is improved! This is some seriously cool stuff. Think about it next time you pick up something heavy, or move some furniture!

Lactic Acid Cycle

After the Creatine Phosphate system is exhausted, the body shifts over to the lactic acid cycle for up to roughly 2 minutes of continuous work (think two minute run or two minutes straight of lifting). This is typically when someone will start to “Feel The Burn”, especially in terms of weight training. The reason this occurs is because there is an accumulation of hydrogen in the muscles, which causes the muscle tissue environment to become more acidic.

What this results in is that fatigue and tiredness experienced when lifting weights. The acidic environment inhibits the working muscles from contracting and causes that burning sensation and fatigue.

So why do we use this system if it’s just going to burn us? That’s some BS.

Not quite, dear reader!

The lactic acid cycle is great in its ability to produce energy quickly and for a relatively long time. If we couldn’t produce energy this way, we’d be pooped much quicker. Here’s how it works:

The cycle is between the working muscles and your liver. The things that are cycling are glucose and lactate. Remember glucose? That’s the primary source of energy and ATP and guess what? It still is in this case! As glucose enters the muscle cell, the glucose will produce some ATP for the immediate energy demand and then be converted to lactate.

Then, this lactate will travel to the liver to be converted back into glucose. When converted back to glucose, the lactate also produces some ATP for immediate use. The lactate (now glucose) will travel back to the muscle cell to produce more ATP and continue the cycle until the hydrogen atoms inhibit further muscle contractions.

As you can probably imagine, this system pretty much produces energy on demand, meaning that there is none stored for future use. The ATP that is synthesized is immediately used.

Takeaways

Once again, this system only lasts for a few minutes, then the aerobic glycolysis systems kick in and produces a TON of energy but at a slow pace. This will be the topic for part 2 next week! Stay tuned! Check out my other articles about the sources of ATP (Protein, carbs, and fat) to learn more about the awesomeness of our body’s interaction with food! Thanks for reading!

  • The body utilizes the macronutrients through different energy systems for different demands of energy
  • Higher energy demand is derived from anaerobic glycolysis systems
  • The Creatine phosphate system is the initial system used for high-intensity work but only lasts a few seconds
  • The Lactic Acid Cycle allows us to work at high intensities for a couple of minutes until muscle contraction is no longer possible. This is accomplished by cycling glucose and lactate between the liver and muscle cells.

 

New Info. About Sodium and Blood Pressure. Is There an Association?

Recent research conducted by Boston University’s School of Medicine has challenged the notion that blood pressure is negatively impacted by sodium intake. Previously, the idea has been that as you increase your intake of sodium, primarily from salt, blood pressure worsens and leads to increased risk for stroke and other complications. Lynn L. Moore and her team presented their research that goes against this idea.

Disclaimer: I was only able to read the abstract, as I could not find the whole study. I am not sure if it’s available publicly yet since it’s a novel study. With that in mind, some of what I say may be misinterpreted on my part simply because I didn’t have complete access to the paper. I will do my best to avoid this while still giving you good, useful information. Hang with me here!

So, what they found was very interesting. First off, subjects were classified into five groups of increasing sodium intake. Over the groups, the average systolic and diastolic blood pressure levels were quite similar¹, even as intake increased.

Next, potassium intake had an inverse relationship with blood pressure¹. Basically, as intake of potassium increased, blood pressure levels fell. No surprise there. In addition, associations for calcium and magnesium intake were noticed that were similar to potassium (inverse relationship)¹.

Lastly, and probably, the most significant finding, the researchers also had a group where they observed the combined effects of sodium and potassium. Those with the lowest intakes of both had the highest blood pressure and vice versa¹.

What does this mean? It means eat your frickin’ vegetables. Vegetables are LOADED with potassium, and people are certainly more likely to be deficient in potassium than sodium. It’s important to note that just because this study did not find an association between blood pressure and sodium intake does not mean you can go down all the soy sauce and salt you want. In many cases, high-sodium foods are those that are highly processed, containing a lot of calories and little nutrients (like potassium).

These findings suggest the same ol’ story: obtain most of your foods from whole sources (whole grains, fresh or frozen fruits and veggies, etc.) and save some room for your personal treats. This study also suggests that you can enjoy high sodium foods in conjunction with a high intake of potassium. As we saw, high intakes of both did not show an increased risk for high blood pressure. Load up your stir fry with vegetables!

Another important note is that this is simply one study on a topic that is controversial. As I said earlier, research has been published to support both sides of the argument. Learn how your body responds to sodium. Try increasing/decreasing your intake for a week or two and check your blood pressure again to see if improvements were made. Or, in the case of increasing it, if there was no change, you may be able to add in more. Keep in mind, if you increase your sodium, your potassium intake should be moving with it.

Athletes and Sodium Intake

This is an important distinction to make. If you’re an athlete, sodium is an essential nutrient that you should not be skipping out on. Sweating results in the loss of sodium. Some people are even known as ‘salty sweaters’ and eliminate a lot of sodium through sweat. If too low levels of sodium in the blood occur, this is known as hyponatremia. The Mayo Clinic notes that these conditions could occur if hyponatremia ensues:

  • Nausea and vomiting
  • Headache
  • Confusion
  • Loss of energy and fatigue
  • Restlessness and irritability
  • Muscle weakness, spasms or cramps
  • Seizures
  • Coma²

Obviously, none of these issues are good for an athlete. So takeaway for this portion of the post is to make sure, if you’re an athlete, that you’re replenishing yourself with not just water, but some type of source that contains sodium and the other electrolytes. This will ensure you’re fully hydrated and ready for whatever is next.

Takeaway Points

  • Enjoy your sodium, but make sure your potassium intake is near similar to your sodium intake (Vegetables and legumes [think beans] are an awesome, easy way to accomplish this)
  • Don’t go HAM on the sodium (lolz, get it?)
  • Learn how your body responds to sodium by playing around with your intake.
  • If you’re an athlete, don’t be afraid to have sodium for training. It’s essential for good workouts and performance.
  • Talk to your doctor about your blood pressure and learn ways of improving it if need be or simply to understand how to manage it better

Have any burning questions or feeling a little salty after reading this? Post your comments below! Thanks for reading!

References

¹http://www.fasebj.org/content/31/1_Supplement/446.6.abstract?sid=f67e9f3b-d62b-49a0-aebc-8393c1f7f4f1

²https://www.mayoclinic.org/diseases-conditions/hyponatremia/basics/symptoms/con-20031445