Vitamin C Vitamin C is probably the most widely recognised of all vitamins. It’s an essential nutrient that must be obtained from the diet; many thousands of years ago, humans lost the ability to manufacture vitamin C in the body. It is destroyed very easily by cooking, storing and food preparation, therefore care needs to be taken to ensure adequate daily intake. Vitamin C is our major water-soluble antioxidant present in blood plasma and cells. This means that it helps prevent oxidation of other water-soluble molecules that could create free radicals – harmful molecules that accelerate the ageing process and cause degenerative disease. Although humans can no longer manufacture vitamin C, fortunately it’s abundant in many fruits and vegetables, therefore is readily available.