Phew…that was something. We ate and we ate, and drank and drank—I thought we are going to burst. Literally. I hope everybody in our Thanksgiving party (over 30 people) survived intact. Being a doctor, and a worrier, the thoughts of what could go wrong were never quite banished by the pleasures of gluttony. What dangers were going through my mind?

 

The burst stomach

Have you ever seen a snake swallowing a whole turkey? You can actually see the poor creature traveling through the long intestines of the tubular glutton. Well, a burst stomach is extremely rare and happens only in rare conditions where the brain center controlling hunger and satiety is malfunctioning. Normal stomach capacity is about 8 cups, although it can range form 4 to 12, according to Dr. Edward Saltzman of Tufts Medical School, quoted in a New York Times article on the hazards of Thanksgiving. But for us regular gluttons, there are more common dangers lurking in stuffing our faces.

 

Heart attacks

This is probably the most serious problem of serious overeating. Here is what happens:

A normal meal of about 1,500 calories sits in the stomach 1-3 hours, depending on the amount of fat in the diet; fat slows down stomach emptying. How is this night different from all other nights? The average American consumed yesterday 4,500 calories and 229 grams of fat, according to the Calorie Control Council (full disclosure: they represent the makers of low-calorie foods). The average time to empty this humongous amount of fatty food is 8 hours. This, in itself, can cause only a sensation of fullness (loosen your belts) and flatulence (leave the room, please). But what goes on in your physiology is more serious: In order for the stomach and intestines to perform their job, they get an increased supply of blood coursing through the arteries and veins that supply them. This blood is diverted from vital organs such as the heart (vital for all of us) and the brain (less vital for some people I know). Now, if instead of 1-3 hours, the blood has to take an 8-hour detour, and a lot more blood diverted, to boot, you can see the stress the heart and the brain are undergoing. In fact, if the blood supply to the heart is marginal to begin with, this massive diversion of blood volume will tip the balance and result in a heart attack.

To add insult to injury, the high-fat content in a typical Thanksgiving meal results in a massive influx of lipids and triglycerides into the blood. This situation, called hyperlipidemia and hypertriglyceridemia, causes an increase in platelet aggregation. Those tiny cells, when sticking together to form a platelet clot, can cause blockage of the coronary precipitating. Yes, you guessed it, a heart attack. The combination of reduced volume of blood flow to the heart and the increase in blood coagulability is more than additive; the risk is not 1+1=2, it is more like 1+1=10.

 

The gall of it all

In order to absorb dietary fat, our digestive system needs to break it up into microscopically small particles. This is accomplished by the bile, a juice flowing from the gallbladder. Sometimes, the solids in the bile precipitate out and form gallstones. They can then occlude the bile duct, the narrow outlet from the gallbladder to the small intestine. When there is a lot fat in the diet, the hormone cholecystokinin signals that a large amount of bile is required. But if the bile duct is occluded, the bile backs up, and the result is excrutiating abdominal pain that may mimic the pain of a heart attack.

 

What about the brain?

Here the consequences can be just as serious. The reason we feel drowsy after a heavy meal is that blood supply to the brain is reduced. This, in itself, never killed anybody. But add to this, the amount of alcohol we consume with the meal—and put us behind the wheel—and you can see why the accident rate is sky high and Highway Patrol is out in force on Thanksgiving Day.

Before you rush to your computers to berate me for omitting your favorite culprit or theory, here is one subject you shouldn’t bother about: The urban legend that the amino acid tryptophan is the culprit of the meal-induced drowsiness. Tryptophan is indeed the precursor of melatonin, the sleep-inducing hormone. But the amounts required to significantly increase the level of melatonin are much higher than even the most outrageously gluttonous feast can provide.

Now that I told you how badly we behaved yesterday, did I restrain myself? As they say in New York, fuhgeddaboudit; I stuffed my face and enjoyed every calorie of it. Today, though, starts the hard task of atoning for my sins. But I enjoyed it while it lasted. I hope you did, too.

Dov Michaeli, MD, PhD
Dov Michaeli, MD, PhD loves to write about the brain and human behavior as well as translate complicated basic science concepts into entertainment for the rest of us. He was a professor at the University of California San Francisco before leaving to enter the world of biotech. He served as the Chief Medical Officer of biotech companies, including Aphton Corporation. He also founded and served as the CEO of Madah Medica, an early stage biotech company developing products to improve post-surgical pain control. He is now retired and enjoys working out, following the stock market, travelling the world, and, of course, writing for TDWI.