Vitamin C strengthens muscles in the elderly
The more vitamin C there is in your blood as you age, the stronger your muscles will be, report Japanese epidemiologists in the Journal of Gerontology: Medical Sciences. The Japanese data suggest that not only foods that are rich in vitamin C, but also supplements containing vitamin C can help maintain strength in the muscles of the elderly.

The researchers studied a group of 655 women whose average age was 75. They measured the concentration of vitamin C in the women's blood and used this data to divide the women into four equal-sized groups: one group with relatively low vitamin C levels, a group with slightly higher concentrations, and so on.Results
The researchers then assessed the women's physical functioning. One aspect they looked at was the women's handgrip strength. They noticed that this strength was significantly greater the more vitamin C there was in the women's blood.

The number of seconds that the women were able to stand on one leg was also greater in the group with high levels of vitamin C in their blood.
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The effect was also visible when the researchers had corrected for the effect of fruit consumption. Fruit is the most important source of vitamin C in the Japanese diet, but fruit also contains many other important nutrients. A high vitamin C level can be an indicator of a high intake of these other substances - but those other substances cannot explain the association.


"However, the statistical adjustment for fruit intake did not attenuate the relationship between plasma vitamin C and physical performance, suggesting that vitamin C did have some beneficial effects independently of other nutrients", the researchers write.That would mean that vitamin C supplements might also play a role in muscle maintenance in the elderly. The Japanese then searched the literature for confirmation of this theory, but did not find any supporting evidence. For every study in which vitamin C supplementation stimulated muscle growth or strength, there was one in which vitamin C had no or even a negative effect.
Animal studies have shown that elderly lab rats build up more muscle strength through a training programme if they are also given extra vitamin C and E in their food. In 2009 Canadian researchers discovered a similar effect in a human study. They discovered that elderly people who do weight training build up more muscle mass if they also take vitamin C and E.
J Gerontol A Biol Sci Med Sci. 2012 Mar;67(3):295-301.