Tryptophan — is an essential amino acid necessary for the synthesis of serotonin, melatonin, and niacin. It plays a key role in regulating sleep, mood, and immune function.
Since the body cannot synthesize tryptophan on its own, it must be obtained from food. Its deficiency can lead to depression, anxiety, insomnia, and decreased immunity, while excess — can trigger digestive disorders and drowsiness.
Health Benefits
- participates in the synthesis of serotonin — a neurotransmitter that affects mood and behavior;
- ensures the production of melatonin, which regulates sleep and wake cycles;
- is a precursor to niacin (vitamin B3), necessary for energy metabolism;
- helps reduce anxiety and improve sleep;
- supports immune function and digestive health.
Daily Requirement and Sources
The recommended daily dosage of tryptophan is 250–425 mg for an adult, or 4–6 mg per kg of body weight. During high stress and physical exertion, the need may increase.
Main sources of tryptophan:
- meat: turkey, chicken, beef;
- fish: tuna, salmon;
- dairy products: cheese, yogurt, milk;
- nuts and seeds: pumpkin seeds, cashews, walnuts;
- legumes: soybeans, chickpeas, lentils;
- grains: oats, buckwheat, whole grain bread.
For better absorption, it is recommended to combine tryptophan with carbohydrates, which facilitate its transport to the brain.
Possible forms and their absorption
Nutrient forms are listed from best to worst:
Symptoms and Consequences of Deficiency
- depression, anxiety, irritability;
- insomnia and sleep disturbances;
- reduced cognitive functions and attention span;
- decreased appetite and digestive issues;
- weakened immune defense.
Chronic deficiency of tryptophan may contribute to the development of mental disorders and metabolic dysfunction.
Possible Risks of Excess and Their Manifestations
- drowsiness, lethargy, fatigue;
- nausea, diarrhea, bloating;
- allergic reactions — rash, itching, swelling;
- serotonin syndrome with excessive intake from supplements: confusion, tremors, tachycardia.
The safe upper limit of consumption — is about 5 g per day. Such dosages are possible only with the intake of supplements and require specialist supervision.
Serotonin, melatonin and niacin
Tryptophan is used for protein synthesis and can be converted into serotonin, melatonin and vitamin B3. Inflammation, stress, B6, iron, magnesium and gut health influence these pathways.
Sleep and mood do not depend on tryptophan alone. Light exposure, caffeine, stress, deficiencies, medications and meal regularity also matter.
Keto and safety
On keto, tryptophan comes from turkey, meat, fish, eggs, cheese, cottage cheese, nuts and seeds. With adequate protein, deficiency is unlikely.
Tryptophan supplements should not be casually combined with SSRIs, MAOIs, triptans or other serotonergic drugs because of serotonin syndrome risk. Depression, panic attacks and insomnia require medical evaluation.