Still Life with a Turkey Pie, by 17th century Dutch artist Pieter Claesz (Wikimedia Commons)
Three thousand five hundred calories in one meal. Maybe you’re so tired after all that turkey, stuffing, potatoes, vegetables, cranberry sauce, and pie because it’s a big job just lifting the fork to your mouth so many times and chewing all that food.
Or maybe, just maybe, it’s those celebratory beers, cocktails or glasses of vino. What do you think?
Blame the turkey?
For years people have blamed the turkey, saying it’s the natural chemical L-tryptophan in it that is the culprit.
But really, does turkey contain a substance that makes you tired? The answer is yes, but it’s probably not the one you’re thinking of. It may be the stuffing, not the tryptophan. And the Thanksgiving meal of potatoes, bread, rolls and pie also have a lot of carbs that may contribute to a feeling of drowsiness.
And then, your innards are so full of food that the body has to use a lot of energy to digest it all, which also may contribute to drowsiness.
Serotonin to melatonin
The Internet is divided on the question as to whether tryptophan induces sleep. A source we’ve used on this blog before, the National Sleep Foundation,  says tryptophan, an amino acid found in turkey, does indeed make you tired because it spurs the body’s production of serotonin, which in turn turns on the melatonin.
Some vitamin companies make pills out of melatonin to help people regulate their sleep patterns and get to sleep more easily, but the National Sleep Foundation says melatonin pills have no effect in improving people’s sleep.
Turkey day food coma
A blog on HealthyWomen.com  calls postprandial somnolence (after-meal sleepiness) a “food coma.” A dietitian in that posting blames the carbs:
‘Carbohydrates have to be present in order for the serotonin levels to be impacted,’ explains Joy Dubost, PhD, a registered dietitian and a spokesperson for the Academy of Nutrition and Dietetics. ‘Thanksgiving turkey plus stuffing might be the combination needed to do that.’
It’s more likely that plain old overeating and possibly alcohol consumption are what create the sleepiness associated with food comas, she says. Those factors, coupled with the tendency for people to be ‘winding down and relaxing, all leads to a sense of being tired.’
But cheese, eggs, yogurt and other kinds of meat, in a word high-protein foods, also contain tryptophan, and those foods don’t have the reputation for making one sleepier than other kinds of foods. In fact, chicken contains more tryptophan than turkey even. But those high-protein foods also contain other substances that block the brain’s uptake of tryptophan, essentially canceling out its drowsy effects.
This video says tryptophan is a necessary nutrient, not a substance to avoid.
But many of us have had that experience at work where we come back to the office or job site and it’s all we can do stay awake. The same thing happens to many people on Thanksgiving and other holidays—whether the host serves turkey or not.
According to the Huffington Post,  when a person eats high-calorie meals with a lot of carbs, sugar and fat, the body produces a lot of glucose. Glucose, a type of sugar, has a big effect on what scientists call orexin neurons in the hypothalamus that produce a protein that regulates wakefulness. This process involving the parasympathetic nervous system makes the body relax and do the work of digestion instead of going out to seek for more food.
Another chemical produced in the body that is released upon eating a big meal is insulin, which is involved in digestion. Insulin induces the body to release more serotonin and melatonin (again), both of which bring on the drowsiness and, oh happy day, feelings of well-being.
What really seals your fate in dreamland, however, is the fact that you probably just ate way too much food. Regardless of whether you even ate any turkey, eating large portions of anything will leave your body with a ton of food to digest. That takes up a lot of energy, so while your innards are doing their work, your brain is signaling to the rest of your body that it’s time to take it easy and reserve energy.
There isn’t much to read in a quick Google search about avoiding drowsiness after a holiday meal, but there is plenty on how to avoid it after a workday lunch. For one thing, it’s natural for a person to feel sleepy about seven hours after waking, says an article  in The New York Times.
Staying awake after tucking in
The Times gives several ways to avoid the post-lunch dip, as it’s called:
Take a short nap, but make you can rest your head on your desk or the back of the office chair.
Try drinking coffee or taking caffeine in other ways. But some people need to avoid caffeine in the afternoon because it can prevent them from getting to sleep on time at night.
Walk around the office or do some exercises. Talk to a co-worker at their desk, which can kill two birds with one stone if you really need to speak to someone about work matters.
Wake up at the same time every morning, and especially try avoid getting up earlier than usual. This can intensify the post-lunch drowsiness.
Finally, make sure you get a sound night of sleep.
There is one way to avoid feeling so sleepy on Thanksgiving or after other holiday meals: Eat much less food. After all, 3,500 calories are a bit much. Especially if you need to drive home, it’s important to remain alert.
What about caffeine?
Well, after a 3,500-calorie turkey meal, four beers or highballs plus a couple of glasses of wine at dinner, it might seem futile to even try to stay awake. And to add coffee on top of a full stomach!? You would feel like a ... well, a stuffed turkey.
If you think caffeine would help, you might try Viter Energy Mints  with caffeine and invigorating B vitamins. The mints are sugar-free and will freshen your breath too if you are at the relatives' house and can't use a toothbrush. We are not saying your breath stinks! (You tell us, but please, observe proper social distancing.)
Heck, just take a nap
Heck, you probably don’t have to work anyway after your holiday meal anyway. Why not just take a nap after your feast? You might as well put all that serotonin and melatonin to good use.
Erectile dysfunction. In combination, those are two of the ugliest words known to man. But can caffeine help you get it up?
Science hasn't found the definitive answer to this question, but one study concluded that fewer men who consume caffeine have problems performing. The study said:
Caffeine intake reduced the odds of prevalent ED, especially an intake equivalent to approximately 2-3 daily cups of coffee (170-375 mg/day). This reduction was also observed among overweight/obese and hypertensive, but not among diabetic men. Yet, these associations are warranted to be investigated in prospective studies