Vitamin C, or L-ascorbic acid, is an important co-factor in eight enzymatic reactions, and necessary for human health. Humans as well as certain primates, guinea pigs, bats and capybaras cannot make vitamin C themselves and must ingest foods containing sufficient amounts of this important vitamin. Insufficient amounts of vitamin C can lead to scurvy, a disease characterized by tiredness, paleness, skin spots and loose teeth. Although scurvy is rare in the Western world, it was once common worldwide and especially prevalent among sailors, who earned the nickname “limeys” after the British government began adding lemon and lime juice in the 1850s to their rum rations to prevent scurvy. While side effects from too little vitamin C can be severe, so too can the effects from ingesting too much vitamin C.
How Much Vitamin C Do People Need?
The Office of Dietary Supplements, part of the United States National Institute of Health, recommends that men over age 18 get 90 milligrams of vitamin C a day, while women over age 18 who are not pregnant should ingest 75 milligrams. During pregnancy, women should get 85 milligrams of vitamin C. And both male and female smokers should take an additional 35 milligrams of vitamin C.
Keep in mind that these amounts are called “adequate intake” amounts, meaning they are the lowest threshold of vitamin C levels people need to prevent scurvy. The actual amount needed for optimal health may be different, and amounts needed by individuals may vary.
Many people take extra vitamin C in the belief that it can ward off the common cold, help them heal faster, or prevent diseases such as cancer and atherosclerosis. The Linus Pauling Institute states that studies do indicate that maximal dietary intake of 100 milligrams of vitamin C does appear to reduce the risk of cardiovascular disease, but the excess amounts should be from dietary sources, not necessarily supplements. When people take too much vitamin C in the form of supplements, certain unpleasant side effects can result.
Side Effects of Vitamin C
Vitamin C is a water soluble vitamin. Excess vitamin C is removed from the body through the urine. However, if too much vitamin C is ingested at once, certain side effects may occur. Most people do not feel side effects until they take as much as 3,000 milligrams. Side effects may include gastrointestinal discomfort such as diarrhea. Other side effects of taking too many vitamin C supplements include the potential to develop kidney stones. Vitamin C may also affect iron absorption, causing excess iron in the body.
Vitamin C in Foods
Vitamin C is a relatively safe vitamin, and it takes an awful lot of it to cause unpleasant side effects. The safest way to enjoy more vitamin C and its potential cardiovascular health benefits is to eat more vitamin C-rich foods. Such foods include citrus foods such as oranges, grapefruits and lemons, which most people think of when they think of vitamin C. But they also include many vegetables. Red and green bell peppers contain abundant amounts of vitamin C, more than the recommended daily amount for both men and women. Among vegetables, broccoli, Brussels sprouts, cabbage, cauliflower, potatoes, spinach and tomatoes also contain good amounts of vitamin C along with other vitamins, minerals, antioxidants and fiber. If you’d like to try taking more vitamin C for health, do it the natural way, through fresh vegetables and fruits.