Vitamin C is a water-soluble vitamin that is found primarily in vegetables and fruit. Many mammals can make vitamin C in their own bodies from glucose, but humans and a few other animals cannot, and have to get it from... Read more
Vitamin C is a water-soluble vitamin that is found primarily in vegetables and fruit. Many mammals can make vitamin C in their own bodies from glucose, but humans and a few other animals cannot, and have to get it from their diet. Vitamin C is best known for supporting a healthy immune system. It also has a vital role in the production of collagen in the body – a protein that is important for the structure of our skin, bones, blood vessels, cartilage and more. Vitamin C is one of the most unstable vitamins in foods – that is, it is easily lost during cooking and even with general exposure to light, air and heat (i.e. in storage).
Primary functions of Vitamin C
How much do we need?
The EU nutrient reference value for vitamin C for adults is 80mg. Nutrient reference values refer to the amount needed to ensure that the needs of nearly all the population (97.5%) are being met.
However, it’s thought that the optimal amount of vitamin C may be much greater than this. Animals make several thousand milligrams (mg) a day in their bodies – and may produce up to tens of thousands of milligrams in some cases. The Linus Pauling Institute advises that 400mg of vitamin C a day is nearer to an optimal and safe level for adult men and women. More than this may be indicated at times of greater need – see Dosages below for more information.
The best food sources of vitamin C include:
As an indication, a kiwi fruit may contain around 80mg of vitamin C, a cup of broccoli (when raw) about 80mg, and half a cup of blackcurrants around 100mg. However, actual levels can be very dependent on how they have been grown and how long – or under what conditions – they have been stored and transported.
Deficiency signs and symptoms*
Symptoms of vitamin C deficiency may include:
When severe, vitamin C deficiency is known as scurvy, and this can cause more severe versions of the symptoms above, as well as diarrhoea, shortness of breath, severe pains in the limbs and the joints, swollen gums and anaemia.
*If you experience any of these symptoms, please consult your doctor or health practitioner.
Forms and bioavailability
There are many different forms of supplemental vitamin C on the market. These include:
Adults: Standard dosages for adults can vary from about 200mg a day to several grams a day. The maximum dose recommended on supplements tends to be between 1,000mg and 3,000mg a day. Some practitioners recommend using vitamin C up to ‘bowel tolerance’ for certain situations or individuals. This means the maximum amount that does not cause digestive irritation for the individual – for some people this may be up to 10g (10,000mg) or more. For general, long-term use, we believe that 500mg a day is a good amount to use, in line with the recommendations of the Linus Pauling Institute. In ‘food-form’ vitamin C supplements, 200mg or less may be enough.
Children: Children’s vitamin C supplements tend to provide no more than about 500mg as a daily dose. Practitioners may advise more than this where required.
What to look out for when buying a supplement
As we saw above, there may not be a great deal of difference in absorption between the different forms of vitamin C.
If you are taking any medications or have any medical condition, please consult your healthcare practitioner before taking vitamin C.
For those not taking medication, vitamin C is generally considered a safe supplement at low or high levels and for most people. ‘Too much’ tends to be very dependent on the individual – if you’ve taken too much (which for most people is somewhere between 2,000 and 10,000mg), then you will experience loose bowels or other digestive upset, and this is an indication that you should lower your dose.
Vitamin C tablets with the synergistic bioflavonoids, and buffered powder. What more do you need?