How to Take Tryptophan for Sleep?
Tryptophan works best taken on an empty stomach before bed. It is an essential amino acid your body cannot produce on its own, It is the starting point for melatonin production, which is why timing and absorption conditions directly determine how well it works.
Tryptophan from food and supplements travels to the brain via a shared transport system that it competes for with other large neutral amino acids. When you take tryptophan after a protein-containing meal, those competing amino acids significantly reduce how much tryptophan reaches the brain. This is why the Thanksgiving drowsiness story is largely a myth: turkey contains tryptophan, but the protein in the meal actively works against it getting to the brain. A supplement taken between meals, or before bed on an empty stomach, works differently.
Tryptophan converts to 5-HTP, then to serotonin, and finally to melatonin. This conversion requires several enzymatic steps, each of which takes time, which is why tryptophan works more slowly than direct melatonin supplementation. For people who experience grogginess from melatonin, tryptophan is worth trying since it works upstream of melatonin rather than replacing it.