Vitamin C is necessary for human growth and development. However, unlike other animals, people must get their vitamin C from food and other sources as the human body does not produce it naturally. Good food sources of vitamin C include fruits and vegetables, especially citrus fruits. Vitamin C can also be produced synthetically in a laboratory.

The most common use of vitamin C is to reduce the risk of the common cold and reduce its severity if you do catch it. In addition, it is used for other infections such as gum disease, acne, skin infections, bronchitis, bladder, prostate, and stomach ulcers caused by bacteria. Vitamin C has also been known to help with depression, dementia, Alzheimer's disease, reducing physical and mental stress, fighting fatigue, and reducing the symptoms of attention deficit hyperactivity disorder.

Some people also believe that taking vitamin C can help improve heart and blood vessel health. The skin can even benefit from vitamin C as it is known to help protect against the sun, pollutants, and environmental hazards. Vitamin C can also be applied directly to the skin to help reduce the damage from radiation therapy.