Find out all about vitamin C, including what it does, how much you need, where to find it, and who might need to supplement their diet
Overview of vitamin C
What is vitamin C and what does it do?
Vitamin C is an essential vitamin, necessary for the healthy functioning of the body.1 Also known as ascorbic acid, vitamin C is a water-soluble vitamin; our bodies don’t store it, so we have to get enough from our diets every day.2
It’s needed for:3,4
- healthy skin, blood vessels, bones and cartilage
- supporting immune function, especially during and after intense exercise
- normal physiological and nervous function
- improved absorption of iron from plant sources
Vitamin C is found in lots of fruits and vegetables, especially citrus fruits and juices, dark green leafy veg, peppers and berries.5 Vitamin C deficiency is rare but can lead to scurvy, which causes symptoms such as fatigue and swollen, bleeding gums.6
Function of vitamin C
What does vitamin C do in the body?
This nutrient has many roles, including:
- an antioxidant – it helps protects cells against damage from free-radicals (oxidation), which has been linked to chronic disease7
- maintaining a healthy nervous system by supporting enzymes that process messages between neurons in the brain8
- contributing to the production of collagen for tendons and ligaments, skin, cornea, bones, blood vessels and cartilage9
- helping the body to absorb non-haem iron from plant sources10
How much vitamin C do I need?
Women and men need 80mg of vitamin C every day.11 That’s the same as half an orange.12
Vitamin C is water soluble so it can’t be stored in the body. This means you need to replace it from your diet every day.13
How much vitamin C do children need?
- 1-10 years – 30mg of vitamin C a day
- 11-14 years – 35mg a day
- 15 years and older – 40mg a day14
Vitamin C foods
Which foods are the best sources of vitamin C?
Foods high in vitamin C include:15
- red and green peppers
- oranges and orange juice
- Brussels sprouts
- other citrus fruits
- dark green leafy vegetables, like spinach, broccoli and cabbage
Vitamin C deficiency
What are the symptoms of a vitamin C deficiency?
Vitamin C deficiency in the UK is extremely rare, as people usually get enough from their diet.
A vitamin C deficiency can lead to scurvy after as little as one month. Symptoms include:16
- skin bruising
- inflamed, bleeding gums
- low energy
- depression and irritability
- joint pain
People with low levels of vitamin C can also develop iron-deficiency anaemia.17
People at risk of scurvy include those whose diets lack fruits and veg, perhaps because of illness, alcohol abuse or smoking: it reduces how much vitamin C is absorbed by the body, increasing your need for the nutrient.18
What happens if I consume too much vitamin C?
High doses of vitamin C may lead to diarrhoea, nausea, vomiting and stomach cramps. It can also cause headaches and insomnia.19
Vitamin C supplements
When should I take vitamin C supplements?
You should be able to get all the vitamin C you need from a balanced diet. But smokers and people who eat very little fruit and vegetables may benefit from a supplement.20
Should children take vitamin C supplements?
The NHS says children under the age of five may not get enough vitamins A and C. So, the government recommends all children aged between six months and five years old take a daily multivitamin containing vitamin C.21
Do women need to take a vitamin C supplement during pregnancy?
There is no specific need, as you should be able to get all the vitamin C you need from a healthy, balanced diet.22
What are the potential benefits of taking a vitamin C supplement?
A 2018 study discovered that taking extra vitamin C could help shorten the length of the common cold.24
Advice is for information only and should not replace medical care. Please check with your GP before trying any remedies.
Written by Carole Beck on November 1, 2018
Reviewed by Dr Carrie Ruxton PhD on November 3, 2018
1. HSIS. Vitamin C (Ascorbic acid). Available from: https://www.hsis.org/a-z-food-supplements/vitamin-c-ascorbic-acid/
2. Joseph Nordqvist. Vitamin C: Why is it important? Available from: https://www.medicalnewstoday.com/articles/219352.php
3. As Source 1
4. NHS. Vitamin C. Available from: https://www.nhs.uk/conditions/vitamins-and-minerals/vitamin-c/
5. MedlinePlus. Vitamin C. Available from: https://medlineplus.gov/vitaminc.html
6. NHS. Scurvy. Available from: https://www.nhs.uk/conditions/scurvy/
7. As Source 4
8. Oregon State University. Cognitive Function In Depth. Available from: https://lpi.oregonstate.edu/mic/health-disease/cognitive-function
9. As Source 4
10. National Institutes of Health. Vitamin C. Available from: https://ods.od.nih.gov/factsheets/VitaminC-HealthProfessional/
11. As Source 3
12. Self Nutrition Data. Oranges, raw, navels Nutrition Facts & Calories. Available from: https://nutritiondata.self.com/facts/fruits-and-fruit-juices/1968/2
13. As Source 4
14. Public Health England. Government Dietary Recommendations. Available from: https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/618167/government_dietary_recommendations.pdf
15. As Source 10
16. As Source 10
17. As Source 10
18. As Source 6
19. Mayo Clinic. Is it possible to take too much vitamin C? Available from: https://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/expert-answers/vitamin-c/faq-20058030
20. As Source 1
21. NHS. Vitamins for children. Available from: https://www.nhs.uk/conditions/pregnancy-and-baby/vitamins-for-children/
22. NHS. Vitamins, supplements and nutrition in pregnancy. Available from: https://www.nhs.uk/conditions/pregnancy-and-baby/vitamins-minerals-supplements-pregnant/
23. Popovic LM, et al. Influence of Vitamin C Supplementation on Oxidative Stress and Neutrophil Inflammatory Response in Acute and Regular Exercise. Available from: https://www.hindawi.com/journals/omcl/2015/295497/
24. Ran L, et al. Extra Dose of Vitamin C Based on a Daily Supplementation Shortens the Common Cold: A Meta-Analysis of 9 Randomized Controlled Trials. Available from: https://www.ncbi.nlm.nih.gov/pubmed/30069463