Almost all animals on earth synthesize their own vitamin C ( ascorbic acid ) from their blood sugar glucose and do not need it in their diet. The few exceptions are humans, other primates, guinea pigs, the red-vented bulbul, the Indian fruit eating bat, the rainbow trout and the Coho salmon. It is interesting to note that humans are missing just one of the enzymes in the sequence of enzymes required to transform blood glucose into vitamin C . Perhaps we still posses the genetic code for this missing enzyme, but we are unable to access it. Judging from the amount of vitamin C synthesized per day by common animals the average person is grossly under-supplied in their daily vitamin C intake. For example when vitamin C needs are given in mg / kg / day we have Goat ( 32 to 190 mg/kg/day ), Cow ( 15 to 18 ), Sheep ( 25 ), Rat ( 39 to198 ), Mouse (33 to 275 ), Squirrel ( 28 ), Gerbil ( 25 ), Rabbit ( 22 to 226 ), Cat ( 5 to 40 ), Dog (5 to 40 ), and Pig ( 8 ).1 Now compare this to the recommended daily allowance ( RDA ) of 0.9 mg / kg / day allotted for humans by the federal government medical professionals.2 Now less you might think that primates are exceptional in their vitamin C needs note that wild baboons have blood levels of vitamin C consistent with 10 mg /kg / day and wild vervet monkeys have blood levels consistent with 3 to 8 mg / kg / day. At this point your common sense should be telling you that the human RDA of 0.9 mg / kg / day is absurd, ridiculous, and some people in government need to leave government. For example the subcommittee on Laboratory Animal Nutrition of the National Research Council has recommended that most primates be fed vitamin C supplements ranging from 1.75 to 3.5 grams a day. Now what about the primate man?