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How much vitamin C?

Did you know that almost all animals have the ability to synthesize vitamin C? Humans lost that ability sometime in the distant past, presumably because it was readily available in the foods early humans ate. It has been estimated that most primates consume several thousand mg of vitamin C daily from all the greens and fruits in their diet. This is close to the amount that most human size animals would be synthesizing every day. So if it only takes about 100 mg to prevent scurvy, why are all these animals "wasting" energy making more? Presumably it is for all the other beneficial actions of vitamin C including anti-viral activity, general immune support, anti-oxidant activity and reduction of heart disease and cancer.


Based upon the general similarity of all species close in size to us, I advise most patients to take 1000 mg of vitamin C twice daily. Due to the short half life of vitamin C, taking it just once a day would result in undesirably low levels for about half the day. In cases of infection, injury, surgery and other physiologic stresses, higher levels of 4000-8000 per day can be useful. Doses of vitamin C which exceed absorption will cause gas or even diarrhea. This is a sign to reduce the size of each dose or perhaps to split the total daily dose into three to four smaller doses in order to help absorption. During the current COVID pandemic I am advising patients to take 1000 mg 3-4 times daily as general immune support which may improve resistance to infection.


The efficacy of vitamin C is enhanced when it is combined with bioflavonoids. Bioflavonoids are a large family of plant compounds that have multiple beneficial actions. One of the best and tastiest sources for bioflavonoids are fruits and berries. The more different colors you eat, the better the variety and potency of the bioflavonoids. So aim too consume a rainbow of foods including all the range of colors from green to red, blue, purple, orange, and yellow every day. Your body will thank you!

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