Source Naturals L-Tryptophan, 500 mg , 120 Capsules
120 capsules · Capsules
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Price history
Best price so far: £22.41 at Iherb on 2 Sept 2026
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About this product
Dietary Supplement Mood, Relaxation, Sleep The essential amino acid L-tryptophan helps support relaxation, restful sleep, and positive mood. It plays a part in the synthesis of both melatonin and serotonin, hormones involved with mood and stress response and sleep/wake cycles. L-Tryptophan also supports immune functions because it is the body's precursor to the kynurenines that regulate immunity. If needed, L-tryptophan converts to niacin in the body, which supports circulation, a healthy nervous system, the metabolism of food, and the production of hydrochloric acid for the digestive system. Source Naturals L-TRYPTOPHAN is extremely pure and is regularly tested to ensure the highest standards of quality.