Interactions of tryptophan with other micronutrients (vital substances):
Tryptophan and niacin
The coenzyme nicotinamide adenine dinucleotide (NAD) can be synthesized in two ways:
- Niacin
- Essential amino acid tryptophan
The synthesis (production) of the vitamin niacin from tryptophan depends on enzymes that require vitamin B6 and riboflavin (vitamin B2) and an iron-containing enzyme. On average, 1 mg of niacin can be produced from 60 mg of tryptophan, which means 60 mg of tryptophan equals one niacin equivalent (NE). This means that adequate tryptophan intake alone could meet niacin requirements. Nevertheless, pellagra studies from the southern United States during the early twentieth century showed that the diets of pellagra sufferers contained enough NE to prevent pellagra, assuming the conversion described above – yet they showed symptoms of deficiency.Another study states that dietary tryptophan content had no effect on the niacin content of erythrocytes (red blood cells) in young men whose niacin levels were depressed due to a niacin-deficient diet.
