Tryptophan is needed for normal growth in infants and for nitrogen balance in adults.
The body uses tryptophan to help make niacin and serotonin. Serotonin is thought to produce healthy sleep and a stable mood.
In order for tryptophan in the diet to be changed into niacin, the body needs to have enough: Iron, Riboflavin and Vitamin B6.
Tryptophan can be found in: Cheese, Chicken, Eggs, Fish, Milk, Nuts, Peanut butter, Peanuts, Pumpkin seeds, Sesame seeds, Soy, Tofu and Turkey.