Nutrition Time – Tryptophan
Many of you might have heard of and even experienced that crazy phenomenon on Thanksgiving where everyone ends up napping at some point during the big day. Some people try to hide it and end up doing the head bob, others just blatantly stretch out and nap away.
Many people blame it on the Turkey and point to the culprit being Tryptophan! “What?” You might ask or “Oh yeah – I know that!”
So, what is Tryptophan and why do most people th ink it makes you sleepy?
First, Tryptophan is naturally found in animal and plant proteins and is an essential amino acid (remember this blog where I talked about protein sources?) and your body can’t make it, so you HAVE to consume it from an outside source (that’s why it’s considered essential). This amino acid is important for the development and functioning of many organs in the body and is used by the body to make niacin, a B vitamin that is important for digestion, skin and nerves, and serotonin.
After absorbing tryptophan from food, our bodies convert it to 5-HTP (5-hyrdoxytryptophan), and then to serotonin. Serotonin is a hormone that transmits signals between nerve cells, causes blood vessels to narrow and changes in the level of serotonin in the brain can alter mood, memory, and sociability. Among other functions, serotonin promotes feelings of calm, relaxation, and sleepiness. Lack of serotonin is associated with depression.
So, many people associate the tryptophan in the turkey to what makes them sleepy because of the supposed increase in serotonin that happens, but THAT’S NOT QUITE RIGHT…
There is a body of evidence suggesting that eating carbohydrates along with protein can increase the tryptophan available to the brain. When carbohydrates are consumed, the body produces insulin, which diverts other amino acids to body muscles but leaves tryptophan untouched. With fewer competitor amino acids in the bloodstream, tryptophan more freely enters the brain, promoting calm and well-being.
So, actually it’s probably all that stuffing, those yams, bread rolls, and pie (carbs!) that make you sleepy and in fact it’s more so that you eat it in copious amounts that makes you tired. The blood in your body has to be recruited to help digest those heaps of food breakdown and that takes a lot of energy.
You can keep telling people it’s the turkey, but ACTUALLY your nap time comes from overeating and/or the high carb foods that in abundance during this holiday. Go ahead and eat the Turkey (sans skin) – it’s high in protein and will help you build muscle, give you energy, and keep that immune system ticking. You’ll be ready to play that backyard game of whatever sport you choose. Then, you can have some candied yams and pie and take a nap. Enjoy the holidays and remember, turkey is good – fat in copious amounts is bad.
[Strand, Erik. “Tryptophan: What Does It Do?” Psychology Today. Sept. 1, 2003. http://www.psychologytoday.com/articles/200310/tryptophan-what-does-it-do]