Ever since the beginning of oxygen-based life, there has been vitamin C. All plants make it from fructose. All animals from glucose. That’s right. Animals make it and in large amounts. 1 gram (1,000mg) is what you get in about 20 oranges. Goats make the human body weight equivalent of over 10 grams and rats about 3 grams.
Why? Because vitamin C is not only an powerful antioxidant, but also has anti-viral, anti-inflammatory and anti-cancer properties. This is the main reason why vitamin C-producing animals have such a low risk of viral diseases and cancer, and why the experimental animal of choice for mimicking human biology is the guinea pig. Guinea pigs, fruit-eating bats, red-vented bulbul birds, a couple of Amazonian fish and all primates have lost the ability to make vitamin C.
Gorillas make up for it by eating 4.5 grams of vitamin C a day from leaves, fruits and roots. Most primates eat at least 1 or 2 grams a day.
We live in a concrete jungle, not a tropical jungle, and eat much less food because we don’t need to as we don’t have to exercise. Modern-day ‘push-button’ life, complete with cars and the internet, is easy. You can just stay at home. No wood chopping, water carrying or need to walk. So, we eat less and less fresh, vitamin C rich food.
So no, a well balanced diet doesn’t give you all the nutrients you need. Whichever way you look at it we need at least 500mg of vitamin C a day (10 oranges worth) for minimal risk of disease (heart disease, cancer, dementia). Studies show that those with good cognitive status consistently have higher vitamin C levels in their diet or bloodstream, while those cognitively impaired have less. 
There’s also a compelling case to take more, circa 8 grams + a day, when under viral attack (see www.vitaminC4covid.com).
If you take more vitamin C than you need, or can absorb, you get looser bowels. That’s called your bowel tolerance level. Most people won’t reach this with up to 3 grams a day. Since vitamin C is water-soluble it is generally in and out of the body in 6 hours. So you get better use of supplements by taking them twice a day, in the morning and afternoon, perhaps with breakfast and lunch.
Most nutritionists take either 1 gram or 500mg twice a day. We recommend you do the same.
If you’d like to know more about vitamin C listen to this podcast interview where Patrick Holford, one of our trustees, interviews vitamin C expert Dr Tom levy, author of Curing the Incurable: Vitamin C, Infectious Diseases, and Toxins. He explains how vitamin C and other antioxidants are the cornerstone of a healthy life – good for brain. Listen here