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Appetite for Construction
Sep 21 2001

By Dr. John M Berardi, Ph.D.
First published at www.t-mag.com.

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A Calorie is a Calorie! (And Elves Live in my Pants)

Q: Okay, Berardi, it's time you cut the crap with all these "special" meal combinations in your diets like Massive Eating and Don't Diet. A calorie is a calorie! Eat fewer calories than you need and you'll lose weight. Eat more calories than you need and you'll gain weight. It's that simple!

A: Nothing about the human body is as simple as your statement implies. Sure, things appear to be simple when you have a very simple understanding of the most preliminary workings of human physiology and nutrient metabolism. Most dietitians, undergraduate students, and individuals who read a lot about nutrition learn just enough to think things are simple without fully understanding them. This is where they become dangerous advocates of such prejudiced statements as "a calorie is a calorie."

Getting back to our undergraduate nutrition "experts," I'm willing to bet that if you asked most of them to define exactly what a calorie is, they simply couldn't tell you despite their "wealth" of knowledge. If that's true, then get as far away from them as you can, just in case ignorance is contagious. Or better yet, print out this column so they can read it and learn something!
Okay, in all fairness, I'll ease up and let you know that while these "calorie is a calorie" types are clearly ignorant in some respects, they're at least definitionally correct. (And yes, I made that word up.) I'll tell you what I mean in a minute.

Basically, what most people commonly call a "calorie" is really a misnomer. When you mistakenly say one gram of protein has four calories, what you should be saying is that one gram of protein has four kilocalories or four kcal. This is because one kcal actually equals 1000 "calories." Over the years, people have mistakenly made the kcal and calorie synonymous in their usage so now one kcal is often mistakenly called one calorie.

With that understood, what exactly is a kcal? By definition one kcal is equal to the amount of energy required to raise one liter of water one degree Celsius. So the energy contained in one scoop of Advanced Protein could either raise the temperature of a 110-liter jug of water by one degree C, or raise the temperature of a one-liter jug of water by 110 degrees C.

So, definitionally, a calorie is certainly a calorie, just like a degree Celsius is a degree Celsius. However, when someone asks the question "Is a calorie a calorie?", they require more information. What they mean to ask is, "When I consume a calorie of protein, does my physiology respond the same way as when I consume a calorie of fat or carbohydrate?" The answer in this situation is a resounding no!

I could write volumes about this in support of my contention that functionally, a calorie is not a calorie, but don't worry, today I'll spare you. Instead let me address just a few points and give a few examples of why a calorie isn't a calorie.

Let's start out with a simple comparison that sounds a bit extreme but will illustrate my point. If I agreed with the idea that a calorie is a calorie, then I'd have to believe that my body would behave the same way if I ate 3000 calories a day from celery (yes, that's a lot of celery) as it would if I ate 3000 calories a day from butter. Is a calorie just a calorie, or might some of the fibrous content in the celery fail to be absorbed, decreasing the amount of calories actually reaching the cells?

Since some of the fibrous calories will indeed fail to be absorbed, we can see that during the first step of physiological food processing (digestion), the inherent caloric value of food is already altered and fewer of the ingested calories reach the cells. So, 3000 calories of celery are certainly different from 3000 calories of butter. If you're eating only celery and 3000 calories constitutes deficit eating for you, then you'll get far less calories than you'd hoped.

In the end, my point here is that reading food labels doesn't give a good indication of the exact amount of calories that'll actually reach the cells for energy provision or storage. Functionally, a calorie is not a calorie.
The next main reason that people ask, "Is a calorie a calorie?" is because they want to try to manipulate their caloric intake so that it'll be below, match, or exceed calorie needs. This is so they can lose, maintain, or gain weight. But the problem with thinking that a calorie is a calorie is that the very act of eating different foodstuffs can change metabolic rate. A good example of this is the thermic effect of food.

The digestion and metabolism of food actually increases the metabolic rate after a meal. Since protein foods have double the thermic effect of food verses carbohydrates or fats, it should be obvious that the metabolic rate will be higher when more protein is consumed. Again, functionally, a calorie is not a calorie!

When on a hypocaloric diet, protein needs are increased. In studies comparing groups on hypocaloric diets that are low in protein and those that are high in protein (calories are the same in both groups), the diets high in protein lead to increased metabolic rates, increased weight loss, and better preservation of lean mass. Clearly, a calorie is not a calorie in this case either.

While the previous paragraphs discussed different macronutrients, even different varieties of the same macronutrients have different physiological effects. When low glycemic carb diets are compared to high glycemic carb diets, it's clear that the groups of individuals eating mostly high glycemic carbs have higher body fat percentages, higher fasting glucose and insulin levels, and have higher risks for cardiovascular disease. Functionally, a carbohydrate isn't even a carbohydrate, let alone a calorie a calorie!

Studies done in rats have shown that when they eat diets of identical calorie levels, their body compositions are dramatically altered by the composition of fat in the diet. When omega-3 fatty acids make up a large percentage of the diet, the rats are lean and muscular. When omega-6 fatty acids make up a large percentage of the diet, the rats are obese. A fat isn't even a fat, let alone a calorie a calorie! (You knew that was coming, right?)

I hope it's getting clear that just because a calorie is a calorie by definition, that doesn't mean this definition has any implications for changing our physiques. Just because a carbohydrate is a carbohydrate by structure, that doesn't mean that different carbohydrate sources behave the same way in the body.

Here's a cool study that illustrates my point quite well. This study was done to compare the effects of twelve weeks of a moderate hypocaloric (high protein) diet and resistance training in male police officers. In this study, there were three total groups - a control group that didn't exercise, and two groups that did. In the two exercise groups, two different protein supplements were used to increase protein intake. Several very telling things emerged from this study:

1) Before the study began, the subjects' diets were analyzed. It turned out that subjects had actually been consuming a hypocaloric diet that was approximately 10 to 20% below their calculated calorie needs (15% protein, 60% carbohydrate, 25% fat). Despite the calorie deficit, they were all between 22 and 35% body fat and had been gaining weight over the previous five years! So if a calorie were really just a calorie, they should've been leaner and losing fat, right? But no, they were gaining fat!

2) In the control group that didn't exercise, the macronutrient composition of the diet remained the same as before the study (15% protein, 60% carbohydrate, 25% fat) but subjects made smarter food choices. They simply consumed fewer simple carbohydrates and ate more complex carbohydrates.

In addition, these subjects ate less food before sleep and more during the active hours of their days. If a calorie were a calorie, we wouldn't expect to see any changes in their body compositions. However, these simple changes led to an average 5.5 pound weight loss and an average 2.5% decrease in body fat. If a calorie were just a calorie, then there shouldn't have been a change in weight or body fat percentage!

3) That's already plenty of evidence to make the next person that says "a calorie is a calorie" eat his words, but let's go ahead and kick him while he's down, shall we? Let's discuss the interesting changes between the two exercise/high protein groups.

These subjects consumed the exact same number of calories as they did before the study. In addition, the two groups consumed the same exact percentage of the different macronutrients as each other (26% protein, 52% carbohydrate, 20% fat) and did the same exercise routine. Interestingly, the subjects consuming one type of protein (a casein and milk protein product) lost almost 6.5 pounds more fat and gained nearly 4.5 pounds more muscle than those consuming another type of protein (whey).

Not only was body composition altered, but the subjects in the casein/milk protein group had a 31% improvement over the whey-only group in muscle strength. If a calorie is a calorie, the two groups should've had the same results. Clearly they didn't, so, yet again, a calorie is not a calorie!

I could go on all day but I'll stop here. From this discussion, I hope it's clear that the old notion that a calorie is a calorie is a dying idea. Anyone who continues to make this assertion is completely wrong due to either a lack of current information or due to a closed mind. Whatever the reason, neither type of person has any place giving out nutritional advice.

Post-workout Drinks? That's old news! Pre-workout Drinks Rule!

Q: Have you read about the new study showing that a pre-workout drink may be better than a post-workout drink for increasing muscle mass?

A: Yes, I most certainly have. The study you mention was recently published in the American Journal of Physiology - Endocrinology and Metabolism by Dr. Tipton and colleagues from the University of Texas Medical Branch (281:E197-E206, 2001).

This study is entitled "Timing of amino acid-carbohydrate ingestion alters anabolic response of muscle to resistance exercise." Let me tell you, this study and the group that conducted it are the real deal. The members of this group are the true pioneers in the measurement of the interaction between exercise and protein metabolism (synthesis and breakdown) as they've consistently provided high quality research showing how to maximize protein synthesis and minimize protein breakdown during and after exercise.

The post-workout knowledge that we have today is due in large part to this group's amazing studies. So after going over the full text article several times with my "fine-toothed comb," I'm not surprised to report that this study is as tight as my girlfriend's perky little be-hind.

Here's the scoop. Researchers brought subjects into the lab the night before the study was to begin and had them fast from 10pm until the next morning. Starting at 6am the next day, subjects were poked and prodded until 8am. During this time, the subjects had catheters inserted into their leg and arm, four blood samples taken, and one muscle biopsy taken. But the fun was just beginning!

Then the subjects performed an intense leg workout from 8am to 9am. This workout consisted of ten sets of eight rep leg presses and eight sets of eight rep leg extensions. During this time, four blood samples and one muscle biopsy were again taken. Next, from 9am to 11am, subjects laid around the laboratory and gave up eight more blood samples and two more muscle biopsies for a grand total of sixteen blood samples and four muscle biopsies. I know what you're thinking, "Where can I sign up?"

Anyway, the purpose of all this blood letting was to measure muscle blood flow, plasma insulin levels, plasma amino acids, skeletal muscle uptake of amino acids, skeletal muscle protein synthesis, and skeletal muscle protein breakdown. The researchers were trying to determine whether an orally administered beverage containing six grams of essential amino acids and 35 grams of carbs (this is the composition of the beverages used in all of their studies) was more effective when given before exercise (PRE) or after exercise (POST).

Now that you have a little basic background on this rather painful study, let's talk about the surprising results:

1) During exercise, blood flow to the legs increased significantly in both groups. However, in the group that drank the beverage before exercise, blood flow increased to a much larger extent (323% increase) than in the group that drank their beverage after exercise (200% increase). Even up to one hour post-exercise, this increase in blood flow remained 66% higher than baseline in the PRE group compared with the POST group (28% higher than baseline).

At two hours post-exercise, the blood flow was back to normal in both groups. This is important because a large increase in blood flow that's saturated with amino acids may lead to more amino acid uptake and eventually, more protein synthesis.

2) Over the course of the entire study, phenylalanine (a representative amino acid used in protein measurement) was taken up by the muscle to a much larger extent in the PRE group (208mg) than the POST group (81mg). This could be due to the increased blood flow discussed above. One important note here is that not all aminos taken up by the muscle are used in protein synthesis.

3) The total amount of the amino acids taken up by the muscle that were actually used in protein synthesis was 180mg for the PRE group and 39mg for the POST group. This indicates that in the PRE condition, most of the aminos taken up were used in protein synthesis (87%) while in the POST condition only 48% of the aminos were used for protein synthesis. It also means that the PRE condition lead to a 351% greater increase in protein synthesis relative to the POST condition.

4) Of the amino acid drink (six grams of orally ingested amino acids, of which 930mg was phenylalanine), about 22% was taken up by the leg muscles during the PRE condition while only about 8% was taken up during the POST condition.

5) There were no differences in protein breakdown between groups.

6) In the PRE group, total protein balance (synthesis-breakdown) was negative at rest, quickly became positive during exercise and one hour after exercise, and returned to zero balance two hours after exercise. In this group, protein balance was a whopping 115 times higher than rest during exercise and one hour after exercise. In contrast, in the POST group, protein balance was negative before and during exercise, became positive one hour after exercise (35 times higher), and returned to zero by the second hour.

So, with these data presented, I'd like to make one point before discussing how we can use this study to our advantage. First, although the pre-workout drink seems to kick butt compared to the post-workout drink, it's important to recognize that if no drinks were taken at all, protein balance would be negative for all the measurement periods examined here. Remember, with no pre or post-workout nutrition, a highly negative protein balance is seen before, during, and after exercise. So clearly, some kind of pre or post-workout nutrition is necessary to build muscle.

Now, what does all this mean to us? In order to stress the importance of these data, I want to say that I've changed my own personal workout drink consumption (with great results) based on this brand new info! In the past I've recommended post-workout drinks like Biotest Surge that consist of the proper ratios of carbs, hydrolyzed proteins, and amino acids to achieve an intake of 0.8g of carbs and 0.4g of protein/kg of body mass (see my "Solving the Post Workout Puzzle" articles, part one and part two). For me, this meant one drink of 72g carbs and 36g of hydrolyzed protein.

However, with these new data, I've been splitting this drink up into two drinks, each containing 36g of carbs and 18g of hydrolyzed protein. I now consume one of the drinks either immediately before I begin lifting weights (within five minutes) or during my training. I then drink the other one immediately after training.

Since the study above showed positive protein balances with both a pre-workout and a post-workout drink, I believe that consuming the appropriate nutrients both before (or during) exercise and then repeating this again after exercise will contribute to an additive, if not synergistic, increase in protein synthesis, leading to enhanced muscle growth.

For Biotest Surge users, this means splitting up your normal serving size into two drinks and consuming one just before or during exercise, and one just after exercise. Then all you have to do is kick back while you synthesize proteins at an alarming rate!

Food, Fun and Football

Q: I see you don't like to combine fats and carbs in the same meal. In effect, you've ruined every snack food I ever ate, including the ones I thought were healthy. So with these guidelines, just what does Mr. Berardi eat when he's watching football?

A: Sorry to have burst your "health food" bubble, but someone had to do it. Since you asked, let me share with you a few food rules that I've found to make a really big difference in keeping me lean and muscular.

Rule #1 - Just because a food is "healthy" doesn't mean it'll give you a body that the ladies want to snack on.

Sitting in my boring old nutrition classes, my chubby RD professors often discussed the health benefits of low-fat cakes and cookies, antioxidant rich chocolate and red wine, cardio protective soy, fibrous vegetarian eating, and high carbohydrate diets. While some of these things may have some health benefits for certain populations (and some do not), not many of the foods or eating strategies these professors discussed were able to help them drop their 30 extra pounds of "winter weight."

It seems like people often try to justify their cravings with this vague concept of "healthy." You know, "I like chocolate and look, it contains antioxidants so it must be healthy." Well, it also contains a whole bunch of sugar and fat. Hmm, is obesity healthy? Remember this, foods that make you look great are most often healthy, but foods that are healthy don't necessarily make you look great. So from now on, choose the foods that are healthy and make you look great.

Rule #2 - Try not to snack.

Whether you're on an Easy Rider style road trip with Dennis Hopper or you're kicking back with your buddies watching the big game, snacking only gets you into trouble. Yep, you're right; this is a tough rule. But think of it this way; if you're eating eight scheduled meals per day (every two to three hours), are you really going to be thinking about food between meals?

Snacking serves to throw off your planned meal schedule at best. At worst, when you do snack, you typically skip meals. Either way, randomly grasping at some bagged up foodstuff throughout the day is probably not the way to reach your goals.

Let's face it, snacking is more psychological than physiological. People often snack because they're bored, not because they're hungry. If you want to look great, stop thinking like every fat, sloppy, untrained, average person out there and start thinking differently. Start thinking of food as fuel. You don't stop at the gas station just because you're bored; you stop because your car needs more fuel.

Rule #3 - Once in a while, throw out the first two rules!

Sometimes it's perfectly acceptable to eat some foods that aren't on your "healthy and make you look good" list. Snacks are okay too occasionally. However, occasionally is the key word. To me this means one meal every week or two; to some, it means one "cheat" meal per day. I think it's best to eat well all week and then plan a day or a single meal where you'll treat yourself to some things that aren't on your meal plan. Eating like this then becomes a real treat while being relatively guilt-free.

Since I follow these rules mentioned above, I usually don't snack unless I'm watching the game on one of my cheat days. If it's my cheat day, I'll snack on foods that don't necessarily follow the "no carbohydrates plus fat" rule. And I promise you, on such days I enjoy these meals so much more because of the fact that I very rarely eat like that.

However, if it's not my cheat day, I simply eat my scheduled protein plus carb and protein plus fat meals when it's time to eat them. I'll make concessions if I'm out while watching games or out on the road. However, in such cases I'll substitute my regular meal with protein bars, protein shakes, or even my very favorite "road meal" - beef jerky and mixed nuts.

While some of you may be shouting, "Come on JB, live a little! Loosen up and have some fun!" my response to you is this - don't worry about me. I certainly live a lot. You see, somewhere along the way people mistakenly associated food with "living" or "having fun." Personally, I believe that there are other things in life much more fun than drinking beer and eating hot wings.