We humans suffer from hypoascorbemia, a genetic defect that restricts us from producing ascorbic acid (vitamin C) internally the way almost all other mammals do.

Hypoascorbemia is a genetic disease caused by a defect in the gene that controls synthesis of the enzyme, L-gulonolactone oxidase, the final one of a series of enzymes utilized by the mammalian liver to synthesize ascorbic acid from glucose. Lack of this active enzyme in the liver restricts humans from producing ascorbic acid internally, a synthesis which is performed by almost all other mammals. This genetic defect disables us from utilizing this internal biochemical protective mechanism, thereby making us vulnerable to arthritis, heart attacks, strokes, the aging process, viral infections, and the common cold.

Humans, other primates, guinea pigs, and a fruit eating bat are the only mammals known to be unable to produce ascorbic acid in their livers. All other mammals synthesize ascorbic acid in substantial amounts. The response of these other mammals to biochemical stress is to increase their production of ascorbic acid, while the response in humans is to further deplete our already low stores of this liver metabolite.

Scurvy is a disease resulting from deficiency of vitamin C (ascorbic acid). Early symptoms include weakness, fatigue, and sore arms and legs. Vitamin C is required to make the building blocks for collagen, carnitine, and catecholamines. It also assists the intestines in the absorption of iron from foods.

Symptoms of Scurvy: malaise, lethargy, shortness of breath, bone pain, muscle pain, skin changes (roughness, easy bruising, pinpoint sized spots of bleeding under the skin), gum disease, loosening of teeth, poor wound healing, dry mouth, dry eyes, edema (swelling, puffiness, fluid retention).

Symptoms of Vitamin C Deficiency:
Skin bruises easily, black and blue marks
Hemorrhages or ruptured blood vessels in eyes
Gums bleed easily when brushing teeth
Loose teeth, loss of dental fillings.
Cuts, wounds or sores heal slowly
Fleeting pains in joints or legs, joint tenderness
Broken capillaries or pink spots on skin
Catch colds or viruses easily
Listlessness, lack of endurance, tire easily
Cuticles tear easily
Nosebleeds
Bloating or puffiness in face
Anemia
Fragile bones
Thinning or premature aging of skin

How Much Vitamin C is Required. Humans receive only tiny milligram amounts of ascorbic acid from dietary sources, whereas the synthesis in an equivalent sized mammal would be many grams per day. An adult gorilla in the wild state consuming enormous volumes of fresh vegetation has been estimated to get about 4 to 5 grams of ascorbic acid per day. Linus Pauling observed that in the 1980s, Purina Monkey Chow provided 70 times more ascorbic acid than was recommended for humans (equivalent to 4.2 grams). David Rowland recommends that to compensate for hypoascorbemia, adults need to supplement within the range of 4,000 to 4,500 mg. of Vitamin C daily.

Reference: Rowland D. Vitamin C: Genetic Nutrient Deficiency. OSP Journal of Health Care and Medicine 2021;2(2).