How much protein is enough?
I’ve written a few summaries on studies, which have looked at how protein intake can have an effect on an athlete’s body composition. I find these types of studies interesting because they show that the RDA for protein consumption (0.36 g/lbs.) is too low for athletes. However, how much protein is enough? Well, a 2014 study may shed a little more light on this.
In a study published in the Journal of the International Society of Sports Nutrition, researchers split 30 lean, resistance-trained men and women into two groups. One group group consumed their normal diet and protein intake, which worked out to be, on average, about 0.82 g/lb. So over twice the RDA. While the other grouped added more protein to their diet for a total of 1.98 g/lb., which is 5.5X the RDA for protein. Note: The high-protein (HP) group was able to meet their protein requirements with shakes.
The researchers had both groups follow their diets for eight weeks while they engaged in weight training. After the 8 weeks, the researchers found that the high-protein group consumed about 800 k/cal more a day then when they had started. Despite the additionally calories for the HP group, mostly coming from protein, there was no statistical differences between groups for body weight, fat-free mass, or fat mass. To say this was an eyebrow raiser would be an understatement.
What this suggests is that if you’re lean and experienced in weight training then you may not need a protein intake higher than 2-3X the RDA if you’re on a “bulk”.
So how come there was no changes in body composition with the increased protein intake? Good question. The researchers suggest that it could of been the thermic effect of the protein, which would increase energy expenditure. However, that seems like an educated guess. Irrespective, the take-home message is that more protein, past a point, isn’t necessarily better.
For more information:
Antonio et al. The effects of consuming a high protein diet (4.4.g/kg/d) on body composition in resistance-trained individuals. Journal of the International Society of Sports Nutrition. 2014 May 12;11:19.