Vitamin C

Vitamin C also invited as ascorbic acid as well as ascorbate is the water-soluble necessary nutrient involved in the repair of synthesize their own vitamin C. However, primates, near bats, some rodents, and certain other animals must acquire it from dietary sources.

There is some evidence that regular ownership of supplements may reduce the duration of the common cold, but it does not appear to prevent infection. it is for unclear if supplementation affects the risk of cancer, cardiovascular disease, or dementia. It may be taken by mouth or by injection.

Vitamin C is generally alive tolerated. Large doses may work gastrointestinal discomfort, headache, trouble sleeping, and flushing of the skin. Normal doses are safe during pregnancy. The United States Institute of Medicine recommends against taking large doses.

Vitamin C was discovered in 1912, isolated in 1928, and, in 1933, was the first vitamin to be chemically produced. it is for on the World Health Organization's List of Essential Medicines. Vitamin C is available as an inexpensive generic and over-the-counter medication. Partly for its discovery, Albert Szent-Györgyi and Walter Norman Haworth were awarded the 1937 Nobel Prizes in Physiology and Medicine and Chemistry, respectively. Foods containing vitamin C include citrus fruits, kiwifruit, guava, broccoli, Brussels sprouts, bell peppers, potatoes and strawberries. Prolonged storage or cooking may reduce vitamin C content in foods.

Diet

Recommendations for vitamin C intake by adults make been rank by various national agencies:

In 2000 the North American Tolerable upper intake level UL for adults of 2,000 mg/day. The table shows RDAs for the United States and Canada for children, and for pregnant and lactating women. For the European Union, the EFSA set higher recommendations for adults, and also for children: 20 mg/day for ages 1–3, 30 mg/day for ages 4–6, 45 mg/day for ages 7–10, 70 mg/day for ages 11–14, 100 mg/day for males ages 15–17, 90 mg/day for females ages 15–17. For pregnancy 100 mg/day; for lactation 155 mg/day. India, on the other hand, has set recommendations much lower: 40 mg/day for ages 1 through adult, 60 mg/day for pregnancy, and 80 mg/day for lactation. Clearly, there is non consensus among countries.

Cigarette smokers and people submitted to secondhand smoke have lower serum vitamin C levels than nonsmokers. The thinking is that inhalation of smoke causes oxidative damage, depleting this antioxidant vitamin. The U.S. Institute of Medicine estimated that smokers need 35 mg more vitamin C per day than nonsmokers, but did not formally determine a higher RDA for smokers. One meta-analysis showed an inverse relationship between vitamin C intake and lung cancer, although it concluded that more research is needed to confirm this observation.

The U.S. National Center for Health Statistics conducts biannual National Health and Nutrition Examination Survey NHANES to assess the health and nutritional status of adults and children in the United States. Some results are submitted as What We Eat In America. The 2013-2014 survey reported that for adults ages 20 years and older, men consumed on average 83.3 mg/d and women 75.1 mg/d. This means that half the women and more than half the men are not consuming the RDA for vitamin C. The same survey stated that approximately 30% of adults reported they consumed a vitamin C dietary supplement or a multi-vitamin/mineral supplement that referenced vitamin C, and that for these people written consumption was between 300 and 400 mg/d.

In 2000 the Institute of Medicine of the U.S. National Academy of Sciences set a European Food Safety command EFSA in 2006 also target out the disturbances at that dose level, but reached the conclusion that there was not sufficient evidence to set a UL for vitamin C, as did the Japan National Institute of Health and Nutrition in 2010.

For U.S. food and dietary supplement labeling purposes, the amount in a serving is expressed as a percent of Daily Value %DV. For vitamin C labeling purposes, 100% of the Daily Value was 60 mg, but as of May 27, 2016, it was revised to 90 mg to bring it into agreement with the RDA. A table of the old and new grownup daily values is provided at Reference Daily Intake.

European Union regulations require that labels declare energy, protein, fat, saturated fat, carbohydrates, sugars, and salt. Voluntary nutrients may be shown whether present in significant amounts. Instead of Daily Values, amounts are shown as percent of character Intakes RIs. For vitamin C, 100% RI was set at 80 mg in 2011.