What Is It?
Vitamin C is a water-soluble vitamin (dissolves in water) and is therefore associated with both intracellular fluids (cytoplasm) and extracellular fluids (blood). Since vitamin C is water soluble, it is difficult to achieve toxic concentrations of this vitamin.
What Does It Do?
Vitamin C supplementation does not produce a dramatic effect (unless you are starting with a rare vitamin C deficiency) however, it does act as an effective antioxidant, both in quenching free radicals and reactive oxygen species as well as regenerating vitamin E in the intracellular fluid. In acute exercise, free radical production is likely and potential DNA damage is a result. Vitamin C removes most free radicals and reactive oxygen species.
In addition to its antioxidant effects, vitamin C can reduce muscle soreness, improve recovery from muscle damage, and normalize stress hormone concentrations.
Where Does It Come From?
Vitamin C is found in many fruits (especially citrus fruits) and vegetables (especially the green leafy ones). It can also be found in tablet form.
How Do I Use It?
Any active person would benefit from 250mg of vitamin C taken 2x per day unless they already have a very high fruit and vegetable intake. Taking more than 250mg of supplemental C at a given time is not advisable as it increases the risk of pro-oxidant effects (vitamin C can oxidize, making it a mild reactive species itself) and oxidative damage.
4/4 - This supplement/regimen has significant scientific backing and can produce significant benefits in most individuals.
3/4 - There exists a sound theoretical basis for its ergogenic effects; may work in certain individuals; further research is needed to elucidate their respective effects.
2/4 - Science is equivocal, animal data and human data may be conflicting; or mechanism of action may be unclear.
1/4 - Little or no science as well as poor theoretical foundation.
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- Alessio, H.M., et al. (1997). Exercise induced oxidative stress before and after vitamin C supplementation. International Journal of Sports Nutrition. 7(1): 1-9.
- Bland, J. (1998). The pro-oxidant effects of vitamin C. Altern Med Rev. 3: 170, 1998.
- Jakemen, P. and Maxwell, S. (1993). Effect of antioxidant vitamin supplementation on muscle function after eccentric exercise. Eur J Appl Physiol 67:426-30.
- Kaminski M, et al., (1992). An effect of ascorbic acid on delayed-onset muscle soreness. Pain. 50(3): 317-21.
- Levine, M., et al. (1998). Does vitamin C have a pro-oxidant effect? Nature. 395: 231-232.
- Podmore, I. et al. (1998). Vitamin C exhibits pro-oxidant properties. Nature. 392: 559.
- Vansankari, T., et al. (1998). Effects of ascorbic acid and carbohydrate ingestion on exercise induced oxidative stress. Journal of sports medicine and physical fitness. 38(4): 281-285.
John M Berardi is one of the world's foremost experts in the field of human performance and nutrition. His company, Science Link, provides unique and highly effective training, nutrition, and supplementation programs for high level athletes as well as recreational exercisers. John is a prolific author and a sought after speaker and consultant. Visit www.johnberardi.com for more information about John and his team. Also, check out his new DVD entitled No Nonsense Nutrition.
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