# tryptophan

/tɹˈɪptɒfən/ (UK) · CEFR C2 · Noun

Source: https://englishreference.com/word/tryptophan
Updated: 2026-10-19

## Definition

an amino acid in foods like turkey, eggs, and nuts that your body uses to make protein and chemicals for sleep and mood.

For teachers: an essential amino acid serving as a precursor to serotonin, melatonin, and niacin, obtained through dietary protein. Humans cannot synthesize it and must obtain it from foods such as meat, dairy, nuts, and seeds.

## Examples

- Turkey contains tryptophan that helps your body rest.
- She eats eggs and nuts for breakfast to get enough tryptophan during her busy training season.
- Researchers link dietary tryptophan to serotonin production, though the popular claim that turkey alone causes drowsiness oversimplifies a complex metabolic pathway.

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