The Truth About Tryptophan by Jessica Mills

Jessica_white- smallWith the holidays right around the corner many of us are thinking about indulging in the fun and festive food. Whether it’s the turkey, ham, mashed potatoes and gravy, or your aunt’s special apple pie, we all have our favorites.  Many believe that turkey is the catalyst to make you sleepy due to the tryptophan, but is there any truth behind that?

First let’s talk about what tryptophan really is. Tryptophan affects our levels of serotonin which helps our body to create vitamin B-3 and melatonin. Tryptophan and its byproducts play a huge role in regulating our mood and sleep cycles. It also helps create a feeling of relaxation. Tryptophan is a very essential amino acid that the body doesn’t produce on its own, so it’s important for us to get it from our diets. Tryptophan is found in all different types of foods including poultry, sunflower seeds, cheese, chocolate, fish, eggs and bananas. Turkey actually contains less tryptophan than most other foods we eat on a daily basis. So why does turkey alone have the reputation for making us sleepy?

Although turkey is a good source of tryptophan, when consumed by itself there wouldn’t be enough to boost levels of serotonin. Tryptophan would need assistance from other foods high in carbohydrates to actually make a difference. So when consumed with  mashed potatoes, rolls, cookies, pies, alcohol, etc. the high levels of carbohydrates combined with turkey affects the serotonin levels causing you to feel tired. The body digests all amino acids, not just tryptophan. It becomes a competition of which amino acids make it to the brain. As Elizabeth Somer, RD stated, “It would be like standing in line when the Harry Potter movie comes out and you didn’t get in line early enough. The chances of getting in to see the movie are pretty slim. Tryptophan has to compete with all the other amino acids. It waits in line to get through the blood-brain barrier and very little of it makes it across.”

Additionally, if you overeat, your body takes a lot more energy to digest all of the food which directs the blood away from other functions of the body such as your nervous system, which would make you tired. As Dawn Jackson Blatner, RD, LDN said, “Don’t incriminate the turkey that you ate, incriminate the three plates of food you piled high.”


The information provided is for general interest only and should not be misconstrued as a diagnosis, prognosis or treatment recommendation. This information does not in any way constitute the practice of medicine, or any other health care profession. Readers are directed to consult their health care provider regarding their specific health situation. Marque Medical is not liable for any action taken by a reader based upon this information.

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