How to hit your daily vitamin C quota and make the most of your health.
Medically reviewed by Dr Louise Wiseman MBBS, BSc (Hons), DRCOG, MRCGP and words by Rhalou Allerhand
What’s all the fuss about vitamin C? Also known as ascorbic acid, vitamin C is an essential vitamin packed with antioxidants that plays a vital role in the body.
So, how much do we need every day, how do we get it and do vitamin C supplements really work? We speak to Sophie Medlin, registered dietitian and owner at City Dietitians about the important role of vitamin C and how to ensure you get the full benefits:
What is vitamin C?
Vitamin C is naturally present in certain foods. It comes with numerous health benefits, but you do need to eat the right foods to ensure you hit your daily quota.
‘Vitamin C is a water soluble, antioxidant vitamin that is found in lots of foods,’ says Medlin. ‘Humans can’t make vitamin C so it is essential that we get it from our diet.’
Why does vitamin C do?
You might be wondering why do we need vitamin C? Vitamin C has many important functions in the body. ‘It’s essential for the production of collagen, the chemical signals in our brains and the metabolism of protein,’ says Medlin.
‘Vitamin C is also an important antioxidant, which means that is can neutralise cell damage, which may contribute to preventing diseases like some cancers and heart disease. Vitamin C also helps in the absorption of plant based iron.’
(We do not have enough evidence yet that wide supplementation with vitamin C could prevent heart disease but research is ongoing in this area.)
Vitamin C is involved in the following processes in the body:
- Protecting cells from oxidative damage caused by free radicals.
- Helping the body to synthesise collagen, which is required in the structure and function of connective tissues, such as skin and bones.
- Maintaining the normal structure and function of blood vessels and neurological function.
- Increasing the absorption of ironfrom plant sources in the intestines.
🍊 Vitamin C is a water-soluble vitamin, so is not stored in the body. The recommended daily intake for an adult is 40mg per day but smokers may need more.
What happens if we don’t get enough vitamin C?
Severe vitamin C deficiency can lead to scurvy, but unless you’re a sailor planning on spending six months or more at sea, it unlikely to be cause for concern.
‘Vitamin C deficiency is rare in modern society,’ explains Medlin. ‘It was first seen in sailors who didn’t have access to fresh food at sea. The condition it causes is known as scurvy and it causes fatigue and weakness of connective tissues such as gums causing tooth loss and our ligaments causing joint problems.’
Best sources of vitamin C
To hit your daily quote, Medlin recommends you aim for your 5 portions of fruit and vegetables per day. ‘Don’t worry if these are fresh, tinned or frozen,’ she says. ‘Often tinned or frozen veg contain more vitamin C than fresh anyway.’
It is a misconception that it is just fruit that contains vitamin C – many vegetables are even richer in vitamin C,
Medlin outlines the following food groups as top 5 sources of vitamin C in our diets:
- Red peppers – 95mg per serving
- Orange juice – 93mg per serving
- Kiwi – 64mg per serving
- Broccoli – 51mg per serving
- Strawberries – 50mg per serving
Do vitamin C supplements work?
The Department of Health advises that you should be able to get all the vitamin C you need from a healthy balanced diet.
‘Supplements aren’t worth it for most people,’ agrees Medlin. ‘But supplements have been shown to shorten the length of a cold, so many have a supplement if they get the sniffles.’
If you do decide to take a vitamin C supplement, take no more than 1000mg a day. It is often recommended not really more than 400mg a day as the excess will be removed in our urine. High doses of vitamin C can also affect blood sugar tests.
Can you overdose on vitamin C?
Vitamin C supplements are considered as likely safe for most people when taken orally or topically at the correct dosage.
‘Because vitamin C is water soluble, overdosing is quite hard work, we just pee out any that we don’t need,’ says Medlin.
Do vitamin C supplements have side-effects?
Dosages above the recommended safety limit in the UK (1000mg) are deemed possibly unsafe and may cause side-effects, but these symptoms are reversed when supplementation is stopped. If you are concerned, visit your GP.
‘Too much vitamin C can lead to stomach cramps and diarrhoea, as the unabsorbed vitamins draw water to the bowel,’ says Medlin.