(Medical Xpress)—A daily vitamin C intake equivalent to eating two kiwifruit a day is required to ensure our muscles maintain optimal levels, researchers from the University of Otago, Christchurch have found.
Professor Margreet Vissers and her team from the Centre for Free Radical Research are involved in a large on-going study to better understand the critical role of vitamin C in the human body. They are also investigating the best way to obtain the vitamin from the diet.
Their paper on the uptake of vitamin C into muscle has just been published in the American Journal of Clinical Nutrition, the most prestigious publication in the field of nutrition science.
The study has shown that skeletal muscle is very sensitive to changes in vitamin C intake and that the vitamin C content in muscle will fall if intake decreases below optimal levels. This is likely to affect muscle function. Muscle is the largest store of vitamin C in our bodies.
Professor Vissers and her team gave 54 males aged between 18 and 35 either half a kiwifruit or two kiwifruit a day over a six week period. They then measured the vitamin C content in muscle and elsewhere in the body.
The researchers found that general energy levels were increased with the 'two per day' kiwifruit dose, and this is likely to reflect the optimal muscle function under these conditions.
She says eating high-value vitamin C foods, like kiwifruit, is the ideal way to maintain healthy levels.
"Many people think that all fruit and vegetables are equally able to supply vitamin C, but this is not the case. The levels in food vary hugely across the spectrum. We should eat a good range daily, but because many fruit contain only one tenth of a healthy daily vitamin C requirement, we would recommend at least one serve per day of a high-value food like kiwifruit. This will help you easily reach an optimal vitamin C intake, as well as delivering other vital nutrients.''