Every year, depending on current thinking, we see new reports in the media discussing the merits of Vitamin C as a cure for colds.
There have been many studies into this and, subject to how the studies were undertaken and how much Vitamin C was used, they all produce different results!
The fact is, Vitamin C is a very effective anti-oxidant that can help to mop up highly unstable molecules – known as free radicals – that are responsible for a whole host of diseases and health problems.
As well as this, studies show that relatively high doses (1000mg+) of Vitamin C can help to inhibit colds and other viruses by providing an environment in which they can’t survive. This means that you’ll get fewer colds that that are less severe and have a shorter duration.
The important part here is the dosage. 1000mg is roughly 20 times the RDA (Recommended Daily Allowance), but the RDA is the minimum you would require to prevent diseases such as scurvy.
Patrick Holford – one of the World’s leading authorities on nutrition and health – quotes an examination of studies that looked at Vitamin C (in 1000mg doses or more) versus the common cold. 37 out of 38 of these studies concluded that doses of Vitamin C at these levels had a protective effect. (* See reference details below)
So, to cut through all the claims and counter claims, it looks like taking 1000mg per day will help keep colds and flu at bay and 2000mg per day will help reduce the length of time and severity of a cold significantly.
On the down side, high doses of Vitamin C can cause diarrhoea in some people and continuous, long term doses of over 1000mg can lead to kidney stones – again, only in some people.
(*Ref: Hemila, H. et al., “Vitamin C and the common cold: a retrospective analysis of Chalmers’ review.” Published in The Journal of American College Nutrition. Vol 14:2.)