Turning to turkey’s tryptophan to boost mood? Not so fast

Every Thanksgiving, myths of the quasi-magical powers of tryptophan rise again.

There’s the turkey/drowsiness myth: Eating lots of juicy turkey meat supposedly makes people feel tired because it contains an amino acid called tryptophan. This molecule travels into the brain, where it’s converted into a neurotransmitter called serotonin, which in turn is converted into a hormone called melatonin. Voila! Sleepiness.

But science and the internet agree: It’s not the turkey’s tryptophan to blame for your post-feast nap. All protein sources, and even vegetables, contain some tryptophan; turkey isn’t at all special in this regard.

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