Vitamin C is an essential water-soluble nutrient found widely in fruit and vegetables. It supports several normal body functions, but high-dose supplements are not a shortcut to preventing or treating disease.
What does vitamin C do?
Vitamin C acts as an antioxidant, supports normal immune function and is needed for normal collagen formation. It also increases the absorption of iron from plant foods. Authorised European claims include contributions to normal collagen formation for skin, bones, cartilage and teeth, protection of cells from oxidative stress, normal immune function and reduction of tiredness and fatigue.
These claims describe normal physiological functions. They do not mean that a vitamin C product cures infections, reverses ageing or treats joint disease.
Food sources come first
Useful sources include citrus fruit, berries, kiwi, peppers, broccoli, cabbage, potatoes and tomatoes. Eating a varied selection of fruit and vegetables also provides fibre and many other nutrients that a single supplement cannot replace.
Long storage and some cooking methods can reduce vitamin C content. Using a mix of raw and gently cooked produce helps maintain variety without needing a complicated routine.
Do different supplement forms work differently?
Vitamin C supplements commonly contain ascorbic acid, calcium ascorbate, sodium ascorbate or combinations with bioflavonoids and plant powders. According to the NIH Office of Dietary Supplements, research has not shown that one common form is generally better than the others.
Choose based on the exact amount, serving, tolerability, added ingredients and how the product fits with other supplements you use.
A verified iWell option
Elexir Vitamin C Complex 120 Tablets provides 500 mg vitamin C per tablet, together with bioflavonoids from quercetin, rutin and acerola plus rosehip powder. The tablets are vegan.
The verified direction is one to two tablets daily with a meal, providing 500–1,000 mg vitamin C. Do not exceed the recommended daily intake. The added bioflavonoids and rosehip are formula features, not permission to promise a superior medical effect.
How much is too much?
High vitamin C intake can cause diarrhoea, nausea or stomach cramps. The NIH lists an adult upper limit of 2,000 mg per day from all sources. People with iron-overload disorders, kidney problems or specific medical treatments should seek individual advice before using high-dose products.
Vitamin C can also interact with some treatments. Tell your doctor, pharmacist or dietitian about supplements you use, particularly during cancer treatment or when managing a diagnosed condition.
How to compare vitamin C products
- compare the amount per full daily serving
- check whether other supplements already contain vitamin C
- choose tablets, capsules or powder based on accurate measuring and tolerability
- review sweeteners, minerals, plant extracts and other added ingredients
- avoid products that promise to prevent or cure disease
Explore the range
Compare live vitamin C products in the Immune System collection, then read the complete product label before choosing.
Official references
NIH Office of Dietary Supplements: Vitamin C
European Commission: Nutrition and health claims
