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Protein For Fat Loss
If you ask any serious bodybuilder what macronutrient is the most important for adding muscle, you can bet your left biceps that the answer will be protein. Not without good reason, as dietary protein enhances muscle gains by creating an anabolic environment via increased protein synthesis and improved nitrogen balance. The fact that dietary protein can help build muscle is old news, but did you know that it can help you get shredded? That’s right; dietary protein not only builds T-shirt-bursting muscle but can also help melt off unwanted fat.
All Calories Are Not The Same
For many years diets have been based on the idea that “a calorie is a calorie” – meaning calories from protein are the same as calories from carbohydrate and fat. They were all regarded as equal in their ability to regulate fat gain and loss. If that theory were correct, all people who had the same calorie deficit would lose the same amount of fat regardless of how they created the deficit. High protein or low protein, high carbohydrate or low carbohydrate, high fat or low fat – none of it would matter. So long as the calorie deficits were the same, weight loss would be identical.
Recent evidence, however, suggests that’s a totally bogus idea. Several studies have shown that highprotein diets cause more fat loss than normal or low protein diets when the calorie counts in the diets are the same. The experiments show quite clearly that high-protein diets have a metabolic fat-loss advantage over normal and low-protein diets. What’s more, a higher-protein diet has been shown to be superior to lower-protein diets in maintaining muscle mass and improving body composition during a diet. Normal or low-protein diets caused muscle loss while a high-protein diet effectively maintained muscle mass and improved body composition. More muscle, less fat – sounds good, yes? You bet your six-pack it does. Additionally, subjects who followed a high-protein plan after the calorie restriction was complete regained less fat and gained more muscle, improving body composition.
Assuming that the fat-loss fairy isn’t sprinkling magic fat dust on the food of high-protein dieters, what explains the superior fat loss that occurs with high-protein diets? The first possibility is diet-induced thermogenesis, defined as “the increase in energy expenditure above basal fasting level divided by the energy content of the food ingested… commonly expressed as a percentage.” Basically, that refers to the food that you eat increasing your metabolic rate.
Protein, carb and fat can affect metabolic rate differently. Diets high in protein have a much greater impact on thermogenesis – heat production – than typical diets. The thermogenic effects of nutrients are approximately 2 to 3 percent for lipids, 6 to 8 percent for carbohydrates and 25 to 30 percent for protein. Higher-quality animal protein induces greater increases in thermogenesis than vegetable protein does.
It’s Hard To Store Protein As Fat
Another aspect of high-protein diets and improved body composition is the fact that protein is relatively “inefficient” energy. That is, it takes more energy to extract the energy contained in the amino acids that come from dietary protein than the energy contained in carbohydrate and fat. Many amino acids are first converted to glucose before they can be oxidized for energy. That process, called gluconeogenesis, occurs in the liver and requires the body to input energy. That makes it less efficient because it’s harder to store fat from dietary protein if the body must expend energy to convert it to glucose. High-protein diets are so energy inefficient that it’s much more difficult to induce fat gain and obesity on a high-protein diet than on a typical diet.
Protein Fills You Up
Besides, high-protein meals are satisfying, so they are very effective at reducing hunger during calorie restriction. Consequently, a high-protein diet not only increases the number of calories your body burns but also prevents you from overconsuming calories. It’s been argued that the fat-burning effect of high-protein diets is greater because so many of them are low in carbohydrates. Proponents of very-low-carbohydrate, or ketogenic, diets claim that their low-carb nature makes them superior to moderate or high-carb diets. Certainly, high-carb diets can be a problem, as it’s impossible to eat both high protein and high carbohydrate while at the same time restricting total calories. Still, the role of dietary carbs has to be accounted for. A recent study examined just that issue by putting one group of subjects on a very-low- carb diet and another on a moderate-carbohydrate diet while keeping total protein and calorie counts constant. At the end of six weeks both groups had lost statistically similar amounts of bodyfat, with the moderate-carb group actually losing slightly more bodyfat, although it was not statistically significant. It is therefore reasonable to conclude that the high-protein rather than low-carb component of the diet causes greater fat loss and increased thermogenesis. High-protein diets also increase the body’s branched chainamino acids. [Editor’s note: Protein is a collection of amino acids, which include the BCAAs.]
The Importance Of BCAAs
The BCAAs are valine, leucine and isoleucine. Unlike other amino acids, they are not metabolized by the liver, so they make it into the bloodstream in similar quantities as foods containing them. Leucine in particular stimulates protein synthesis, or the process of making new body proteins from amino acids, in muscle. That requires a good deal of energy and can account for quite a few calories burned. A recent study demonstrated that subjects with chronically elevated BCAAs are leaner, more insulin sensitive and
resistant to diet-induced obesity. Leucine itself has been shown to increase insulin sensitivity, essentially enabling insulin to shunt carbohydrates into cells more effectively. BCAAs may also play a role in the muscle-sparing effect of high-protein diets. Supplementing a normal-protein calorie-restricted diet with leucine increases muscle retention better than an unsupplemented, normal-protein diet. It appears that leucine and the other BCAAs are at least partially responsible for many of the metabolic advantages of high-protein diets.
Get 30% Of Your Calories From Protein
By now you’re itching to know what specific conclusions we can draw and recommendations we can make from the research. Keep in mind that there’s no one diet for everyone because everyone tolerates different amounts of calories, carbs and fats when losing bodyfat. Where protein is concerned, however, the studies seem to suggest that getting 30% of your calories from protein is enough to cause a significant difference in bodyfat loss and muscle retention. As for grams of protein per pound of bodyweight, anywhere from 0.7 grams to 1.25 grams per pound can cause significant differences. If you’re more endomorphic and tend to store fat more easily, it might be wise to aim for the higher end of the range and keep carbs down in order to take advantage of the thermogenic effect of greater protein intake. Ectomorphs and mesomorphs, on the other hand, may want to aim more toward the low to middle range.
BCAAs Supplements Enhance Protein
Additionally, evidence suggests that supplementing with BCAAs may enhance the effect of a high-protein diet. I recommend 10 to 20 grams of BCAAs per day, depending on weight and body type. Try to spread your protein and BCAAs, if you choose to supplement with them, over four to six meals, always bearing in mind that a proper resistance-training and cardio program are essential to reaping the maximum benefits from any nutritional plan.