If quinine severely reduces tryptophan uptake, then it follows that people with preexisting tryptophan deficiency, a common occurrence in undernourished populations, would be especially at risk ...

If quinine severely reduces tryptophan uptake, then it follows that people with pre-existing tryptophan deficiency, a common occurrence in undernourished populations, would be especially at risk ...

However, many foods besides turkey contain tryptophan, including cheese, chicken, egg whites, fish, milk, peanuts, pumpkin seeds, sesame seeds, soybeans and sunflower seeds, according to the ...

Such is the case for indoleamine 2,3-dioxygenase 2 (IDO2), an enzyme expressed in the brain and metabolized by the tryptophan–kynurenine pathway (TKP).