- Vitamin C may help your immune system fight off infections from some bacteria and viruses.
- Consuming enough vitamin C is also important because it might lower your risk of stroke.
- Topical application of vitamin C is good for brightening your skin and stimulating collagen production.
- This article was medically reviewed by Samantha Cassetty, MS, RD, nutrition and wellness expert with a private practice based in New York City.
- Visit Insider’s Health Reference library for more advice.
Vitamin C, also known as ascorbic acid, is used for various processes in the body including building bone, collagen, and muscles. It’s also important for wound healing. But the human body doesn’t produce vitamin C on its own, meaning you need to consume it from dietary sources.
Here are five benefits of vitamin C, and how to know if you’re getting enough of it:
1. Vitamin C might help your immune system
“There is some limited evidence that extra-high doses of vitamin C boost the immune system and help fight off the common cold and other types of infections,” says Ben Tanner, a physician assistant and nutrition expert. An extra-high dose of vitamin C is somewhere around 200 mg. “The evidence is pretty weak, but the benefits of taking some extra vitamin C when you are sick probably outweigh any risks, for almost everyone.”
A paper published in the journal Nutrients in 2017 notes that some cells in the immune system require vitamin C to do their jobs, meaning a high supply â€” about 100 to 200 mg a day â€” of vitamin C can enhance immune system functioning.
Additionally, vitamin C deficiency can increase your risk of becoming susceptible to some bacteria and viruses. That said, the Mayo Clinic stresses there is no evidence that vitamin C prevents the common cold.
2. Vitamin C is an antioxidant that can prevent cell damage
“[Vitamin C] is an antioxidant, which limits the damaging effects of free radicals,” explains Amanda Izquierdo, MPH, RD, a Chicago-based registered dietitian.
Free radicals are compounds produced both by normal cell processes and by external sources like pollution or cigarette smoke. If your body accumulates too many free radicals, this can lead to something called oxidative stress, which is linked to ageing and health conditions including:
- Rheumatoid arthritis, a type of autoimmune arthritis that causes joint swelling and pain
- Cardiovascular diseases like high blood pressure
- Neurodegenerative diseases like Alzheimer’s disease, Parkinson’s disease, and multiple sclerosis
Antioxidants â€” like vitamin C â€” can help prevent the accumulation of free radicals. That said, the International Journal of Biomedical Science study concludes that “further research is needed” before experts can unequivocally recommend antioxidant supplements as preventative treatments for some of these conditions linked to free radicals.
Read more about the benefits of antioxidants.
3. Vitamin C might lower your risk of stroke
Thanks to vitamin C’s role as an antioxidant, it may also play a role in heart health.
The researchers concluded that people with a high vitamin C intake â€” ranging from an average of 45 mg to 1,167 mg a day â€” were less likely to have had strokes. Those who took between 200 mg and 550 mg a day of vitamin C saw the greatest reduction in stroke risk.
While researchers are unsure exactly how vitamin C reduces the risk of stroke, they believe it may be due to the vitamin’s ability to lower blood pressure and reduce inflammation.
4. Vitamin C may be good for your skin
A 2017 study published in Nutrients found that normal skin contains high levels of vitamin C because it plays two important roles in skin health: assisting with collagen production and preventing sun damage.
Vitamin C can help stimulate collagen production in the skin. Collagen is a protein that provides skin with its structure and stretch. As we age, our body naturally produces less collagen,resulting in wrinkles and fine lines. Topical application of vitamin C may help regenerate lost collagen.
Vitamin C also removes oxidants caused by exposure to ultraviolet radiation, which helps to prevent sun damage. Ultraviolet radiation causes premature ageing of the skin, resulting in wrinkles, hyperpigmentation, and skin sagging. Vitamin C also inhibits the production of melanin â€” a pigment that can cause dark patches on the skin.
5. Vitamin C helps iron absorption
Vitamin C helps with the absorption of non-heme iron, which is a type of dietary iron found in plant-based foods like leafy vegetables, nuts, and grains. Iron is important for maintaining healthy blood, as it’s a major component of hemoglobin. Hemoglobin is a protein found in red blood cells that transports oxygen to cells and organs. When someone is iron deficient, they develop a condition called anemia that causes muscle weakness and fatigue.
Because vitamin C assists with iron absorption, people with anemia may benefit from taking iron supplements along with vitamin C supplements, or another source of vitamin C like a glass of orange juice.
How much vitamin C do I need?
The amount of vitamin C you need varies depending on your age, according to the National Institutes of Health.
There are not many risks associated with consuming too much vitamin C, Tanner says, because it’s a water-soluble vitamin. That means that any excess is simply flushed out of the body in urine.
“One exception would be people with a condition called hemochromatosis, who have excessively high iron levels,” he says. “Vitamin C increases iron absorption in the gut.”
Izquierdo says that most people don’t experience issues from consuming too much vitamin C, but potential symptoms include:
Where can I get vitamin C?
“The obvious food sources of vitamin C are citrus fruits,” says Tanner. “But many other fruits and vegetables are also good sources.”
Foods rich in vitamin C include:
The bottom line
Vitamin C plays an important role in many processes within the human body, from improving skin health to lowering your risk of stroke. Most people will hit their daily requirements without much effort, provided they eat plenty of fruits and veggies.