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Protein. It’s every bodybuilder’s favorite macronutrient and for good reason. Protein is extremely essential, super satiating and amazingly anabolic. Protein is awesome… but you’re consuming too much of it.
Like most myths, the belief that you should take in 1g/lb of body weight has become so deeply entrenched in the fitness world that its validity is rarely questioned. Strangely, very few people think it’s a bit too accidental that the optimal amount of protein your body can assimilate in a day is exactly 1g/lb. 2.2g/kg doesn’t sound as right, does it? Of course, I know you read my articles for their scientific merit, so let’s look at the literature on the effects of daily protein intake to find out if 1g/lb really is the optimal amount of protein intake for maximum muscle gains.
Studies on Optimal Protein Intake
All values in the bullet point list below are expressed as grams of protein per pound of body weight per day. All of these studies controlled for energy intake, either based on individual requirements or by setting energy intake to be equal in all experimental conditions, so that only the proportion of protein in the diet varied between groups. If the studies were based on unreliable methods such as nitrogen balance, a marker of lean body mass changes, I only included them if they controlled for sweating and dietary adaptation periods.
• Tarnopolsky et al. (1992) observed no differences in whole body protein synthesis or indexes of lean body mass in strength athletes consuming either 0.64g/lb or 1.10g/lb over a 2 week period. Protein oxidation did increase in the high protein group, indicating a nutrient overload.
• Walberg et al. (1988) found that 0.73g/lb was sufficient to maintain positive nitrogen balance in cutting weightlifters over a 7 day time period.
• Tarnopolsky et al. (1988) found that only 0.37g/lb was required to maintain positive nitrogen balance in elite bodybuilders (over 5 years of experience, possible previous use of androgens) over a 10 day period. 0.45g/lb was sufficient to maintain lean body mass in bodybuilders over a 2 week period. The authors suggested that 0.55g/lb was sufficient for bodybuilders.
• Lemon et al. (1992) found no differences in muscle mass or strength gains in novice bodybuilders consuming either 0.61g/lb or 1.19g/lb over a 4 week period. Based on nitrogen balance data, the authors recommended 0.75g/lb.
• Hoffman et al. (2006) found no differences in body composition, strength or resting hormonal concentrations in strength athletes consuming either 0.77g/lb or >0.91g/lb over a 3 month period.
Now, there are some old studies based on nitrogen balance that suggest higher protein intakes are beneficial, but, as I stated above, these studies were methodological abominations. Nitrogen balance is a notoriously unreliable method to assess changes in lean body mass, especially at higher amounts, and these studies didn’t control for sweating or dietary adaptation. Significant changes in dietary protein intake are known to result in negative nitrogen balance for up to 2 weeks after the change, even when sufficient energy and protein is consumed. Furthermore, these studies didn’t exclude androgenic-anabolic steroid users though they studied competitive athletes. (Tarnopolsky et al., 1988).It’s no wonder many of these studies didn’t get translated and remain no more than a shady abstract on PubMed, if they’re even featured on there.
A Bayesian Bodybuilder stomping on a methodological abomination.
Based on the sound research, many review papers have concluded 0.82g/lb is the upper limit at which protein intake benefits body composition (Phillips & Van Loon, 2011). This recommendation often includes a double 95% confidence level, meaning they took the highest mean intake at which benefits were still observed and then added two standard deviations to that level to make absolutely sure all possible benefits from additional protein intake are utilized. As such, this is already overdoing it and consuming 1g/lb ‘to be safe’ doesn’t make any sense. 0.82g/lb is already very safe.
The picture below summarizes the literature. As you can see, 1.8g/kg (0.82g/lb) is the point at which additional protein intake ceases to yield any benefits.
http://bayesianbodybuilding.com/the-myth...ybuilders/