I ran across this interesting study from Germany: It seems that Michael Ristow and his fellow researchers have noticed an odd confluence of chemistries. With a small number of volunteers (19 without previous exercise training and 20 with prior exercise training) the researchers subjected their groups to the same vitamin supplementation and exercise rigimens for 4 weeks. The vitamins examined were a combination of vitamin C (1000 mg/day) and vitamin E (400 IU/day). All of the subjects participated in 20 sessions of about 2 hours of supervised training over 4 weeks.
What the researchers after found doing painful things like muscle biopsies and plasma samples was that reactive processes were blocked by the antioxidant vitamins. Those very processes cause good things like insulin sensitivity that exercise and muscle building. The suggestion is that anti-oxidants may block some of the healthful benefits of exercise.
His Take: Ok, first of all, don’t panic. This study suggests not proves that it is possible to do overdo it on certain antioxidants, specifically vitamins C and E. This is a small study that takes a first look at very complicated biochemical processes. There is a good illustration on page 4 of the paper that shows what is going on. The antioxidants are doing their job preventing oxidative stress to the muscles. The oxidative stress is what sets off the other cascades of chemistry that create the benefits of exercise. We are still pretty early in understanding the right dosing of many of these vitamins to balance effects like this with prevention of disease down the road.
I have personally been on and off of 1000 mg of Vitamin C daily over the last several years based on Linus Pauling’s original thoughts. Mind you that even the Linus Pauling Institute has dropped back to recommending the RDA of most vitamins. This 2003 paper from the Journal of Nutrition points out that, “Consumption of 100 mg/day of ascorbic acid is found to be sufficient to saturate the body pools (neutrophils, leukocytes and other tissues) in healthy individuals.” So the dietary pros think the amount in a large grapefruit should be enough and certainly by the time whatever is in your multivitamin is added on, you should be in the clear. It probably doesn’t make sense to add on 1000 mg more of Ester-C.