Tryptophan & Turkey

America’s annual day of feasting – Thanksgiving – is right around the corner and the main entrée is bound to be turkey on most American’s dinner plates.  Every year, somebody will be blaming the turkey for the excessive sleepiness most of us will feel after stuffing ourselves silly.  Why is the poor turkey usually to blame?  Everyone will answer it’s because of tryptophan found in turkey.  But is turkey really the primary reason for the all-consuming tiredness that hits out of nowhere after eating such a large feast?

The truth is you could completely omit turkey from the menu and you are still going to find yourself in a sleep induced fog enveloping you like a warm blanket once the meal is over.  Turkey does contain tryptophan or L-tryptophan which is an essential amino acid.  Amino acids are the building blocks of protein and Tryptophan is one of the 20 amino acids that has been documented to produce sleepiness.

Tryptophan is necessary to help make niacin, a B vitamin important for digestion, skin and nerves, and it also makes serotonin. Serotonin is a chemical in the brain that acts as a neurotransmitter that can bring about a feeling of well-being and relaxation.  The body cannot make serotonin without tryptophan.  Serotonin, in turn, is needed to make melatonin, a hormone that exerts a calming effect on the body which helps regulate sleep and wake cycles.

So yes, turkey does contain tryptophan but it contains no more of the amino acid than some other foods do.  In fact, there are other foods containing more tryptophan than turkey including chicken, pork, fish, and cheese. But no one ever states they feel like taking a nap after eating a pork loin.  That’s because like turkey, there are other amino acids present in these food besides tryptophan that are not inducing sleep. 

So, if turkey is not the sole cause of you wanting to lie down in a prone position for the rest of the afternoon, what are other reasons for this?

·         Carbohydrate rich meal

The amino acid tryptophan is found in protein rich foods such as turkey but eating a carbohydrate rich meal is what increases the level of tryptophan that leads to the production of serotonin.  Typical carbohydrate rich foods served at Thanksgiving tend to be mashed potatoes, stuffing, dinner rolls, sweet potatoes and cranberry sauce.  These carb-infused foods stimulate the pancreas to secrete insulin causing some amino acids competing with tryptophan to move from the bloodstream into the muscles cells. This causes a higher concentration of tryptophan in the bloodstream resulting in serotonin production creating that sleepy feeling.

·         Fats slow down digestion

The fat found in those buttery mashed potatoes and Aunt Elsie’s rich apple pie will put the brakes on digesting your Thanksgiving dinner.  It takes a lot of energy to digest fat.  In order for that to happen, the body will redirect blood to your digestive system to begin working.  With the blood flow concentrated in your abdominal area away from your brain, this leaves you feeling tired after eating a fat-rich meal.

·         Alcohol intake

If alcoholic beverages are a part of your dinner plans and often times they are, remember that alcohol is a central nervous system depressant.  This will only enhance the feeling of taking a siesta soon after eating.

·         Stuffing yourself

Digesting a large meal is a huge task for the body requiring a lot of energy.  The stomach is full of food waiting its turn to be broken down and absorbed which means blood rushes away from other organ systems including the nervous system to concentrate on the task at hand.  This means nothing will sound better to you than taking a nice, long powernap.

·         An atmosphere of relaxation

No doubt, holidays can be stressful.  There’s the planning, cleaning house, preparing food which all can create a lot of tension and anxiety.  Often the most relaxing part of a Thanksgiving celebration is likely sitting down to eat the meal.  It provides an opportunity to actually sit down and unwind spending time with family and friends you enjoy being with.  That tranquil feeling will usually linger after the meal to where you feel like shutting your eyes dreaming about what a good time you had. 

It comes down to the fact that turkey should not be the fall guy (or food) for you wanting to catch some shut-eye after the Thanksgiving meal.  It’s really a combination of time off from work, visiting with family, feeling more relaxed and oh yes, that piled-high plate of food you just gorged yourself with.