By Stephanie Schupska
University of
Georgia

True or false? The L-tryptophan contained in turkey is what
makes a person sleepy after a holiday dinner.

False. L-tryptophan can make a person feel sleepy, but it is
not from eating turkey. University of Georgia extension
specialists say that intense desire to nap after a holiday meal
comes from all the calories people stuff in their stomachs
during holiday dinners.

“You could even have the meal without the turkey and still have
that drowsy effect,” said Kelly Bryant, a UGA Cooperative
Extension nutrition specialist.

The turkey gets a lot dumped on it this time of year. From
gravy to cranberry sauce to mayonnaise on sandwiches, the bird
has several toppings and one issue to deal with.

“It’s a common myth that the turkey is to blame for making you
sleepy,” Bryant said.

The myth starts out with a strong base, because L-tryptophan,
an essential amino acid, has a documented sleep-inducing
effect.

L-tryptophan is used in the body to produce the B-vitamin,
niacin. The body uses niacin to produce serotonin, a
neurotransmitter that exerts a calming effect and regulates
sleep. But L-tryptophan needs to be taken on an empty stomach
and without any other amino acids or protein in order to make a
person drowsy.

Also, L-tryptophan is found in almost any food that contains
protein, like chicken and cheese, Bryant said.

It’s not just the holiday protein that’s causing the desire for
post-dinner shuteye. That sleepy feeling can be blamed on
several things.

“Potatoes, sweet potatoes, breads. The large quantity of
starches is what causes you to feel sleepy,” Bryant said. “It’s
a combination of several things, the type of food, the amount
and the alcohol served.”

It takes a lot of energy to digest a large meal. Blood is
pulled to the stomach from other parts of the body. This causes
drowsiness, she said.

“On holidays, we tend to overeat,” Bryant said. “The average
number of calories in a Thanksgiving meal can range depending
on the meal.”

The average holiday meal, she said, contains between 2,000 to
3,000 calories, equal to or more than the amount of calories
that most people need for a whole day.

Bryant offers several suggestions for balancing holiday
meals:

• Have lower-calorie foods for breakfast and dinner. It’s about
what you eat throughout the day.

• Eat balanced meals and include fresh vegetables with a
balance of protein and carbohydrates.

• Limit portions and eat dessert in moderation.

• Eat slowly. It gives the stomach time to tell the brain that
it’s full.

• After the meal, take a walk or do some type of activity with
your family and friends.

But if you are unable to stick to these suggestions, Bryant
says give in and just take a holiday nap.

(Stephanie Schupska is a news editor with the University of
Georgia College of Agricultural and Environmental Sciences.)