Sources of vitamin C · Vitamin C and health · Health risks due to excess. Vitamin C is one of many antioxidants. Antioxidants are nutrients that block some of the damage caused by free radicals. Vitamin C deficiency is rare in developed countries, but it can occur with a limited diet that provides less than 10 mg a day for a month or more.
Although a cup of orange juice or half a cup of red pepper would be enough to meet the recommended daily intake of vitamin C. The foods richest in vitamin C are citrus fruits, green peppers, strawberries, tomatoes, broccoli, white potatoes and sweet potatoes. The Hujoels study also found that recovering from a vitamin C deficiency takes a long time and requires higher levels of vitamin C. And, since vitamin C is one of the nutrients sensitive to stress, Moyad says that maintaining vitamin C levels may be an ideal marker for overall health.
The Hujoels discovered that the data from this unique study, which has been a cornerstone used by WHO and other agencies to establish healthy levels of vitamin C in humans, required more than just an “ocular” data evaluation method. A major limitation when interpreting many of these studies is that researchers did not measure vitamin C concentrations before or after supplementation. Because of the improved absorption of non-heme iron by vitamin C, there is a theoretical concern that a high intake of vitamin C could cause excessive iron absorption. Serious side effects caused by too much vitamin C are very rare, because the body can't store the vitamin.
In general, currently available evidence does not indicate that vitamin C, taken alone or with other antioxidants, affects the risk of developing AMD, although some evidence indicates that AREDS formulations could delay the progression of AMD in people at high risk of developing advanced AMD. The inconsistency of the data generally prevents the establishment of a specific recommendation for vitamin C above the recommended daily dose for these conditions. This vitamin C intake is more than double the daily intake of 45 mg of vitamin C recommended by the WHO, but it is consistent with the editorial panels of the National Academy of Medicine and (other) countries, they add. Fortunately, many of the best dietary sources of vitamin C, such as fruits and vegetables, are often eaten raw.
Although the body maintains a small reserve of these vitamins, they must be taken regularly to avoid a shortage in the body. People who take these medications on a regular basis should discuss their vitamin C intake with their healthcare providers.