Vitamin C is a water-soluble vitamin, meaning that your body doesn't store it. We have to get what we need from food, including citrus fruits, broccoli, and tomatoes.
You need vitamin C for the growth and repair of tissues in all parts of your body. It helps the body make collagen, an important protein used to make skin, cartilage, tendons, ligaments, and blood vessels. Vitamin C is needed for healing wounds, and for repairing and maintaining bones and teeth.
Vitamin C is an antioxidant, along with vitamin E, beta-carotene, and many other plant-based nutrients. Antioxidants block some of the damage caused by free radicals, substances that damage DNA. The build-up of free radicals over time may contribute to the aging process and the development of health conditions such as cancer, heart disease, and arthritis.
It's rare to be seriously deficient in vitamin C, although evidence suggests that many people may have low levels of vitamin C. Smoking cigarettes lowers the amount of vitamin C in the body, so smokers are at a higher risk of deficiency.
Signs of vitamin deficiency include dry and splitting hair; gingivitis (inflammation of the gums) and bleeding gums; rough, dry, scaly skin; decreased wound-healing rate, easy bruising; nosebleeds; and a decreased ability to ward off infection. A severe form of vitamin C deficiency is known as scurvy.
Low levels of vitamin C have been associated with a number of conditions, including high blood pressure, gallbladder disease, stroke, some cancers, and atherosclerosis, the build-up of plaque in blood vessels that can lead to heart attack and stroke. Getting enough vitamin C from your diet -- by eating lots of fruit and vegetables -- may help reduce the risk of developing some of these conditions. There is no conclusive evidence that taking vitamin C supplements will help or prevent any of these conditions.