There have been countless studies performed on the role of protein in the muscle growth process to try and determine exactly how much protein you should consume to build muscle mass. Recently, several studies have looked at the role that dietary protein plays in helping you lose fat, and more importantly, helping you keep it off!
One thing scientists have discovered is that eating lean protein foods is important for regulating body composition because it decreases your appetite.
In a 2003 study reported in the journal, Current Opinion in Clinical Nutrition And Metabolic Care (2003; 6(6): 635-638), protein was shown to be more satiating (made you feel fuller) than both carbohydrate and fat both in the short term and the long term.
Eating more lean protein foods has also been proven as an effective strategy to help you burn fat and keep it off because of something called, "dietary thermogenesis" (also known as the thermic effect of food).
In a study published in the British Journal of Nutrition in 2005 (93(2): 281-289), researchers followed a group of 113 overweight subjects after 4 weeks of a very low calorie diet, through a 6 month period of weight maintenance. The subjects were divided into a protein group or a control group. The protein group was simply given an extra 30 grams of protein per day on top of their usual diet.
The researchers found that during weight maintenance, the group with the higher protein intake was less likely to regain the lost weight, and any weight gain in the protein group was lean tissue and not fat. The results were attributed to higher thermic effect and a decrease in appetite.
Although calories will always be the bottom line when it comes to fat loss, studies such as these are confirming what bodybuilders have known for a long time: That calories are not the only factor that can influence your body composition. Your protein intake and your ratios of protein relative to carbohydrate and fat can clearly play a key role in helping you lose fat and keep the fat off.
None of this is news to bodybuilders or to anyone who is already familiar with bodybuilding-style nutrition programs such as Burn The Fat, Feed The Muscle. But it's interesting that such positive results were achieved in studies where protein was increased so conservatively – as little as 30 additional grams of protein per day or a 20% increase above traditional protein recommendations.
Many bodybuilding-style diets (such as Burn The Fat and Body For Life) call for as much as 30%-40% of the total daily calories from protein and some competitive bodybuilders crank up the protein (temporarily) to as much as 50% before competitions.
I'm curious to see if any research is ever conducted with these more aggressive protein intakes. If so, my guess is that we will find once again, that the bodybuilders are ahead of the science when it comes to the manipulation of diet for improving body composition.
The take home lesson is simple: If you remove some carbs and put in some protein – nothing too radical; even as little as trading 30 grams per day of carbs for 30 grams of lean protein – this small change in your diet may decrease your appetite, decrease your body fat and help you keep the fat off after you lose it.
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