When Good Protein Goes Bad … How Much Is Enough?
Sunday, June 13, 2010
A recent article in Consumer’s Reports caused quite a stir, for example see blog link below:
The issue was the amount of heavy metals found in supplements. Just for the record, it seems that the “culprits” were supplements that included not only whey proteins but other ingredients to provide a supplement mix. I didn’t see any mention of products just with pure whey/proteins as being problematic. This doesn’t mean there was a serious problem with the products cited since there have been challenges to the methodologies used for that research.
What I found more interesting was the other buzz around the article implying that too much protein was bad for your health and nobody needs extra protein in their diet. I may be over simplifying but I believe the overall message most people would take away from the article is avoid protein supplements and avoid eating too much protein … both are bad for you.
Consumer Reports aren’t alone in the belief that too much protein is bad for you, a 2009 article cited a long list of statements in educational materials warning of the dangers of excessive protein (Lowery, L. M. & Devia, L. (2009). Dietary protein safety and resistance exercise: what do we really know? J Int. Soc. Sports Nutr, 6, 3). These ranged from kidney damage, liver damage, loss of calcium from bones, dehydration, to plain old weight gain. Of course too much of anything is likely to have undesirable effects but does one have to be very careful not to exceed recommended daily allowances? What is safe?
So here is the Coles Notes Version of What I Learned:
1. This topic has been around for some time back, as far as 1865, even the League of Nations (1936) came up with a recommended daily amount.
2. The recommended daily amount for health adults is 0.8g/kg or just under 0.4/lb (1kg = 2.2 lb).
3. According to the International Society of Sports Nutrition, this amount is not sufficient for people who are engaged in regular exercise or sports – an amount of 1.4g to 2.0g/kg (0.6g to 1.0g/lb) is safe and may have desirable benefits.
4. The amount of protein required varies by the type of exercise. For endurance exercise the recommended range was 1.0 to 1.6g/kg (0.5g to 0.7g/lb), for intermittent sports like soccer, basketball, mixed martial arts recommended level was 1.4g to 1.7g/kg (0.6g to 0.8g/lb) and for strength/power exercise the range was 1.6g to 2.0g/kg (0.7g to 0.9g/lb). Note the amounts recommended in the magazines for bodybuilding/power lifting tend to be in the 1 to 1.5 g per pound range.
5. Protein intakes at these levels for active individuals are not harmful to kidney functions or bone density.
6. You can get all the protein you need from whole foods, but protein supplements can help ensure you get all you need.
7. Protein doesn’t hang around so distribute intake during the day to ensure an adequate supply for your needs. Of course more is needed around training times/post-training.
8. Whey powders don’t taste like chicken!
The above points are based on a position statement published by the International Society of Sports Nutrition (Campbell, B., Kreider, R. B., Ziegenfuss, T., La, B. P., Roberts, M., Burke, D. et al. (2007). International Society of Sports Nutrition position stand: protein and exercise. J Int.Soc.Sports Nutr, 4, 8). A similar finding conclusion that there was no concrete evidence that protein at these levels was harmful is also included in the Lowery and Devia (2009) article, but with less certainty about the safety.