Brightly coloured peppers and cherry tomatoes

How to spot vitamin C deficiency symptoms and what to do

Would you know the signs of low vitamin C levels in yourself or your family?

Everyone knows that oranges contain vitamin C, but you might not know exactly how this vital vitamin works in our bodies – or if you’re getting enough.

Get the lowdown on this essential nutrient and find out how to meet yours and your loved ones’ daily vitamin C needs.

What is vitamin C?

Also known as ascorbic acid, vitamin C was first identified in the 1930’s by researcher Dr Albert Szent-Györgyi. Although it’s hard to imagine now – people would once get very sick or even die  due to lack of vitamin C in their diets.1

Luckily, understanding of vitamins have changed, and vitamin C deficiency in the UK is very rare.

However, having low vitamin C levels is not uncommon, especially in people who don’t eat many fruits and vegetables for various reasons.

Vitamin C has a range of functions, including a key role in the growth and repair of all our body’s tissues. Vitamin C also helps our bodies absorb iron from plant sources.2 Vitamin C is a water-soluble vitamin. This means our bodies can’t store it, and each time we urinate, we lose a little vitamin C. Our bodies can’t make it, either. Therefore, we need to make sure we have food or drink containing vitamin C every day to prevent us from running low.3

Why do we need vitamin C?

  1. It’s an antioxidant
Vitamin C is also a powerful antioxidant that can protect our cell membranes from oxidative damage caused by free radicals.4

  1. It supports immunity
The reason vitamin C is so intrinsically linked with the prevention of colds is because it really does benefit our immune system. In 2017, researchers at the University of Helsinki found that taking up to 8mg of vitamin C every day can shorten the length of colds.5

  1. It is a beauty aid
Looking for a beauty booster? Vitamin C plays an important role in stimulating the production of collagen in our skin needed to give plumpness and elasticity to skin and reduce the appearance of wrinkles.6

Lack of vitamin C is also associated with dry skin and brittle hair.

How to ensure you’re getting enough

To ensure you’re getting enough vitamin C, make sure you eat a wide range of fresh fruits and vegetables. You can find vitamin C in foods such as citrus fruits, berries, peppers, tomatoes, green vegetables and potatoes, especially new potatoes.7 It’s possible to get all the vitamin C you need by eating a healthy diet, but some people top up with a supplement, especially if they don’t always eat at least 5 portions of fruit and vegetables per day.8


Adults need a minimum of 40mg of vitamin C a day.9 This is easy to get through a healthy diet with lots of fruit and vegetables, including red peppers and oranges.

Vitamin C deficiency symptoms go away quickly on you start getting vitamin C, whether through diet or supplements.

What happens if you don’t have enough?

A serious deficiency of vitamin C is rare but can lead to scurvy, a disease once widespread among fruit-deprived sailors in the Victorian era.

Scurvy is only a risk if you don’t have enough vitamin C in your diet for at least three months.10 However, low levels of vitamin C aren’t uncommon. The early symptoms of vitamin C deficiency can include:11
  • tiredness and weakness
  • irritability
  • easy bruising
  • dry skin and hair
  • sore or bleeding gums
The following groups are especially susceptible to low vitamin C, and should be vigilant about vitamin C deficiency symptoms:12
  • Those with drug or alcohol issues who may not have a healthy, balanced diet
  • People with a serious aversion to fruit and vegetables
  • Older people with a reduced appetite and who may eat a less varied diet
  • Smokers are more at risk of a vitamin C deficiency, as smoking reduces the body’s absorption of the vitamin13
  • Pregnant and breastfeeding women because they need higher amounts of vitamin C

Which type of vitamin C is best?

It’s always best to get your vitamins from a healthy, balanced diet if you can.

If you want to take a vitamin C supplement, the choice can be bewildering. You can find it in tablet, capsule, chewable, effervescent, and liquid forms. Vitamin C is found in a lot of multivitamins too.

Most vitamin C supplements will come in the following forms:

  • ascorbic acid – vitamin C in its simplest and most common form
  • time-released vitamin C – this releases the vitamin slowly over several hours, providing better absorption and longer-lasting action
  • Ester-C® – a more gentle form of vitamin C, ideal for sensitive stomachs
  • with bioflavonoids – powerful plant compounds for added immune support

Vitamin C is well-tolerated by the body, and any excess not used is excreted in urine.

However, be careful not to overdo it. People taking too much vitamin C – 1000mg and over – may experience stomach cramps, diarrhoea and wind.14 These symptoms should disappear once you reduce your dose.

Last updated: 17 June 2020

Vitamin C