For years textbooks, many “experts”, and the government have said that athletes and bodybuilders do not need more than the recommended daily allowance of protein( 0.6-0.9 grams of protein per pound of weight for very active athletes). Many even suggest, that it may be toxic or unhealthy, to have a high protein diet similiar to what bodybuilders eat. Bodybuilders for decades have taken large amounts of protein, well beyond these recommendations.

Why bodybuilders eat high protein diets:

Bodybuilders during bulking phases, take extra amounts of calories beyond maintenance(daily calorie requirements). This in turn allows them to gain weight, with the goal of it mostly being muscle. Bodybuilders do this because gaining muscle without extra calories is very difficult because if you don’t gain weight, losing fat and gaining muscle simulataneously can only happen to a certain extent. There is only 3 macronutrients you can choose from in a diet; protein, carbs, or fat. If you ate the recommended daily allowance of protein on a calorie surplus, you would be eating mostly carbs and fat. This would leave you bloated, fat, insulin tolerant, and unhealthy. If you are trying to build mainly muscle, then it would make sense that a large amount of your calories should be protein, the building blocks of muscles.

Protein also doesn’t convert to glucose as easy(and therefore stimulate insulin as much), so it is a much “cleaner” way to bulk when trying to get excess calories. If you had a balance of protein (say 30%) of your calories, instead of about 15% on a lower protein diet, your weight gains will be leaner. Protein also helps aid fat loss and muscle preservation during dieting.

The government and many experts, don’t take into account that bodybuilders are not trying to maintain themselves like the average joe. Bodybuilders require more protein and calories because they are breaking the muscle down and then trying to gain more muscle(or maintain large amounts of it). During dieting they are not trying to simply lose weight like the average couch potato, but instead only fat, while trying to maintain their hard earned muscle.

Studies supporting high protein diets:

While there is research supporting that extra protein intake is needed for athletes and bodybuilders, there is little supporting very high protein intake(well past 1 gram of protein per pound of bodyweight) will give even better muscle growth.

The only one I could find that is commonly cited at many other places is published in Nutr. Metabolism 12:259-274, done on 10 polish powerlifters. They found that even when they more than doubled their protein intake past the recommended daily allowance, half of them were still in negative nitrogen balance. In other words, half were still losing muscle because they weren’t getting adequate protein even at that amount.

One study done by Dr. Lemon and published in Nutrition Reviews,” (54:S169-175, 1996), showed strength athletes needed about 0.8 grams of protein per pound of bodyweight to maintain nitrogen positive balance(sign of muscle growth).

Dr. Lemon also has suggested previously that:

This is an important quote because it’s an admission that they really don’t know the optimum protein intake for muscle growth. So if they don’t know the answer, who does? Pro-bodybuilders of course have the answer. I’ll take the advice of pro-bodybuilding mass monsters like Ronnie Coleman and Jay Cutler, who have built themselves up to almost 300 lbs ripped, through very high protein dieting. There has never been a professional bodybuilder that didn’t get to that without a very high amount of protein in their diet. I think part of the reasons why there is lack of studies on very high doses of protein, is probably because researchers aren’t interested in the more extreme protein diets that are well above 1 gm / lb bodyweight.

There is also many studies showing higher protein diets helped fat loss during dieting. One study by Dr. Donald Layman at the university of illinois, had women on high carb low protein diets and high protein low carb diets. Both groups did resistance training for 11 weeks. The high protein dieters lost 22 lbs but only one pound of muscle. The high carb dieters lost only 15 lbs , but also lost 2 lbs of muscle(one more lb than the other group). This study shows that not only did the high protein diet do better at muscle preservation, but it also helped aid fat loss.

Dr. Layman is a well known research, who has done a lot of research over the years on protein intake and fat loss effects. Here is a quote from him on his feelings of high protein diets during dieting:

Layman is recommending above 1.5 grams per kilogram, which is above 0.7 grams per pound of bodyweight. For a 200 lb overweight individual, that is 140 grams of protein. Notice he is recommending amounts significantly higher than the average recommended dosages. He doesn’t say either, what an optimum amount of protein intake is for fat loss. Many studies have also found that older people require a higher protein intake too.

When is it too much protein in a bodybuilder diet?

What we see from the trend in the protein studies out there, is that there is definite benefits to higher protein intakes. The problem lies in the failure for science to have the answer on how much protein is the optimum intake for the most muscle growth or fat loss. So science doesn’t have the answer yet, but bodybuilders have done well on very high protein diets, so the answer for now is with them I believe.

Bodybuilders often recommend around 1.5 grams of protein per pound of bodyweight. Some advocate much higher. Eventually increasing your protein will hit the point it’s unhealthy and overkill. In body physiology, everything works on the “law of diminishing returns”. As you increase your protein diet, eventually the gains will start diminishing per unit of increase. For example, increasing from 1.5 grams to 2 grams per pound of bodyweight is likely to not have the same muscle growth effect as increasing 1 gram to 1.5 grams. Pro-bodybuilders are at the top because they are willing to take massive amounts of protein, even if it only results in a few percent improvement in muscle gains, than if they had done half.

Too much protein is the point, where the cons outweighs any negligible gains in muscle growth. Like with everything else we ingest, having too much protein could be unhealthy and very inconvenient. Protein does cause extra stress on the kidneys and liver. Drinking a lot of water helps ease the stress brought by digestion and elimination of protein in the liver and kidneys. Many health experts believe that high protein diets pose no health risk provided you drink plenty of water, the amount
is not too excessive, and you have no kidney or liver disease. The answer to a near optimum amount for muscle gains, yet still also being a healthy amount for the kidneys and liver, is probably somewhere in around the 1.5 grams per pound mark.