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5 Responses to “Tired? You're not filled with tryptophan, but with food”

  1. Matt Fisher says:

    I’m sure this is true, but I’m also pretty sure the tryptophan myth predates the 1990s by at least a decade.  I can remember reading it in a glossy magazine (People?) in a house I didn’t live in after 1982.

  2. Dan Hibiki says:

    the holiday tradition of Blaming post Thanksgiving Lethargy on Tryptophan has been replaced with the holiday tradition of articles explaining that Triptophans in the Turkey isn’t what makes you drowsy.

  3. Nick Weaver says:

    Mythbusters also covered it:
    Control, Trytophan tablets, Big Turkey Dinner, Big Dinner with turkey replaced with protien powder, small turkey dinner heavy on the turkey.  Control and Small dinner with lots of turkey == Not Drowsy.  All others == Drowsy.

  4. Torrance Doucheton says:

    Another theory is the postprandial alkaline tide:  with food in your stomach, you must increase your H+ production to maintain a low gastric pH.  Every time your parietal cells produce H+ for the stomach, they must also produce an anion that goes somewhere else.

    The anions produced are bicarbonate (HCO3-), and they go to the blood.  This postprandial alkalosis is believed to have inhibitory CNS effects.  (That’s one theory, anyway.)

    IMO, it doesn’t seem accurate to make the link between increased intestinal blood flow and feeling tired.  Intestinal blood flow is increased after a meal, but blood is being shunted from skeletal muscles and peripheral circulation.  The brain is what determines if you are tired or alert, and the brain always gets preferential treatment when it comes to blood flow and nutrients–it will be the last organ to have blood diverted from it.  Furthermore, wakefulness and sleepiness are functions of neurotransmitters like GABA, histamine, and acetylcholine, which are delivered by neurons, not blood (and perhaps bicarb plays a role also).

  5. Wayne Dyer says:

    Anyone who’s eaten a big Tex-Mex meal can tell you tryptophan is not required.