Mnemonic

Vitamin C Functions

A memory aid for the roles of ascorbic acid.

Expansion

Collagen hydroxylation, antioxidant activity and iron absorption

Expansion

Functions

  • Cofactor for prolyl and lysyl hydroxylase in collagen synthesis
  • Antioxidant, regenerating vitamin E
  • Reduces dietary iron from ferric to ferrous, enhancing absorption
  • Cofactor in carnitine, noradrenaline and bile acid synthesis

Scurvy develops after about 8 to 12 weeks of deficiency, and every feature follows from defective collagen:

  • Perifollicular haemorrhage and corkscrew hairs
  • Bleeding, swollen gums and loose teeth
  • Easy bruising, poor wound healing, reopening of old scars
  • Impaired bone growth in children, with subperiosteal haemorrhage
  • Anaemia, partly from bleeding and partly from impaired iron absorption
  • Fatigue and arthralgia

At risk: severe dietary restriction, alcohol dependence, isolated older people, psychiatric illness, and restrictive eating disorders. It still occurs in high income countries and is easily missed.

Treatment produces a dramatic response within days, which is itself diagnostically supportive. Note that high dose supplementation causes oxalate stones and interferes with glucose meters.