What is vitamin C?

Vitamin C, also known as ascorbic acid, is a water-soluble vitamin that is essential for human health It is a water-soluble vitamin, meaning it is not stored in the body and must be obtained through dietary sources.. Vitamin C is a powerful antioxidant that helps to protect the body from free radical damage, and is also involved in the formation of collagen, the production of hormones, and the absorption of iron.

How does it work?

Vitamin C works for medicinal purposes by serving as an antioxidant, which helps to neutralize harmful free radicals in the body. Additionally, vitamin C is involved in the production of collagen, which is essential for the health of skin, bones, and connective tissue, and is also involved in the production of hormones and neurotransmitters, such as norepinephrine and serotonin.

What are the active ingredients that are important for its medicinal properties?

The active ingredient in vitamin C is ascorbic acid, which is essential for human health.

What forms does it come in?

Vitamin C can be found in various forms including fruits and vegetables, oral supplements (tablets, capsules, and powders), intravenous injections, and topical creams and serums.

What can happen if I have an imbalance or deficiency?

A lack of vitamin C can cause a deficiency, which can result in symptoms such as fatigue, weakness, joint and muscle pain, and a tendency to bruise easily. In severe cases, a deficiency of vitamin C can lead to the development of scurvy, a condition that affects the gums, skin, and bones.

When was it first used for medicinal purposes?

Vitamin C rich foods have been used since Ancient times to treat various conditions. It was first discovered for its medicinal properties in the 1700s.

What does Vitamin C help with?

Vitamin C is a nutrient found in fruit and vegetables. Your body cannot make it, and it stores very little. People take it as a pill, a powder, or a skin serum.

The evidence is strong in some places and thin in others. It is well established that vitamin C helps the gut take up iron. For colds, trials found shorter colds, not fewer of them.

• Getting more iron from food and iron pills
  Strong evidence — human absorption studies; well established nutrition science. Vitamin C is well established to help the body absorb non-heme iron. That is the iron in plant foods and in most iron tablets. Taken with an iron-rich meal or an iron pill, it raised absorption by two to three times.
  Evidence grade A · Traditional tier T0
• Colds and flu
  Strong evidence — many randomised trials of regular daily supplements. Trials of regular daily vitamin C found shorter colds and milder symptoms. They did not find fewer colds in most people. The effect looked stronger in people under heavy physical stress, such as athletes and soldiers.
  Evidence grade A · Traditional tier T0
• Skin firmness, dryness and lines
  Good evidence — human trials of pills and skin serums run over several weeks. Skin holds one of the body's highest stores of vitamin C. In trials lasting several weeks, both pills and serums led to measured gains in firmness and moisture, and less deep wrinkles. Some work also found dark spots faded.
  Evidence grade B · Traditional tier T0
• High blood pressure
  Good evidence — clinical trials showing small, repeated drops. Clinical trials found modest drops in both the top and bottom blood pressure numbers. The change was mild but showed up across trials. Researchers think this comes from more flexible blood vessel walls, but that is a proposed mechanism.
  Evidence grade B · Traditional tier T0
• Ageing eyes: cataracts and macular degeneration
  Good evidence — one large randomised trial of a four-nutrient formula, plus observational data. Vitamin C is one of the four nutrients in the AREDS formula. In that trial, the formula slowed the progress of age-related macular degeneration. People with more vitamin C in their diet and blood had lower cataract risk, but that link is observational.
  Evidence grade B · Traditional tier T0
• Healing after injury or surgery
  Early evidence — studies in people who were low in vitamin C. Vitamin C is known to be needed by the enzymes that stitch collagen fibres together. That is basic nutrition science. People who were low in it healed more slowly, and in those people supplements brought healing speed back to normal.
  Evidence grade C · Traditional tier T0
• Low mood and feeling stressed
  Early evidence — small studies in people with low blood levels of vitamin C. In studies of people with low levels, supplements improved mood scores. Reported stress and anxiety scores also fell. Vitamin C is known to be needed to make norepinephrine and serotonin, two brain chemicals, and the adrenal glands store a lot of it.
  Evidence grade C · Traditional tier T0
• Sore muscles and slow recovery after hard exercise
  Early evidence — small supplement studies, mostly in endurance athletes. Supplement studies found less muscle soreness after intense workouts. Blood markers of inflammation were also lower. Most of this work was done in endurance athletes, so it may not carry over to everyone.
  Evidence grade C · Traditional tier T0
• Bleeding gums and worn joints
  Evidence doesn't support this — observational links only; no trial on file for either use. Bleeding, spongy gums are a classic sign of scurvy, the disease of full deficiency. In surveys, people with even mild low levels had worse gum health and more periodontitis. Higher levels were also linked to less cartilage loss in osteoarthritis, but such links are not proof.
  Evidence grade D · Traditional tier T0

What Vitamin C has not been shown to do

• Regular vitamin C did not cut the number of colds people caught in the general population.
• It has not been shown to work as a standalone answer for high blood pressure; the drops found in trials were small.
• Faster healing showed up in people who were low in vitamin C, not in people who already had enough.
• It has not been shown to rebuild cartilage or turn back osteoarthritis.
• Mood gains were seen in people with low blood levels, not in people whose levels were already fine.
• Vitamin C contains no iron itself, so it has not been shown to stand in for iron treatment in anemia.

How to read this:

Each use above has its own grade, because the studies behind them differ. A means steady results from randomised human trials. B means at least one good human trial. C means small or mixed human studies. D means the human evidence is weak or conflicting. Insufficient means no human study at all. This page lists options and what studies found. It is not medical advice, and it is not a promise of what will happen for you. Talk with your doctor or pharmacist before you start, above all if you take other medicines.

What can Vitamin C help prevent?

• Scurvy (vitamin C deficiency disease): complete prevention with adequate intake
• Upper respiratory infections in high-stress populations (athletes, military personnel) — regular supplementation reduces incidence
• Age-related cataract progression: higher long-term intake consistently linked to reduced risk
• Iron-deficiency anemia worsening: pairing with iron prevents absorption failure
• Gout flares: higher vitamin C intake associated with lower uric acid levels and reduced gout risk in observational studies

Which foods are rich in it?

1. Oranges
2. Bell peppers
3. Kiwifruit
4. Broccoli
5. Strawberries
6. Pineapple
7. Mango
8. Tomatoes
9. Papaya
10. Cantaloupe

What are possible side effects?

Vitamin C is generally well tolerated and has few side effects. The most common side effects include:

• Upset stomach
• Diarrhea
• Nausea
• Heartburn

Taking high doses of Vitamin C can also cause rashes and kidney stones in some people.

What's the recommended daily dose?

The recommended daily dose of vitamin C for adult men and women is 75-90 milligrams per day.

How many days does it take to work?

The effects of vitamin C supplementation can vary depending on the individual and the condition being treated. Some people may notice a difference in as little as a few days, while others may take several weeks to see a noticeable effect.

What time of day is best to take it?

Vitamin C can be taken at any time of day and does not have to be taken with a specific meal.

Is it best to take it with or without food?

Vitamin C can be taken with or without food, but some people may experience gastrointestinal symptoms if taken on an empty stomach.