Gifts, holidays carols, seasonal decorations, and mulled drinks are all great, but is there really anything better about the holidays than the abundant freedom to nap?

You’ve just wrapped up a festive feast with your family, and everyone mutually agrees to go their separate ways so they can sleep for an hour or two, with no alarm established, no schedule for the remainder of the day required. That’s the beauty of the food coma.

A Look into the Science of Food Comas

Whether you take pleasure in the experience of a nap prompted by a food coma or not, it is plausible that you are acquainted with the phenomenon. It is a frequently referenced rationale for the sensations individuals experience following a substantial meal — however, is it genuine, or are we simply averse to movement when excessively full?

The food science and history podcast Gastropod explored the unexpectedly intricate subject of food comas this week, featuring expert guests Subha Mani, Justine Hervé, and Nikolay Kukushkin who illuminated all that we must understand regarding this phenomenon.

Understanding a Food Coma

A food coma is not the same as a true coma, referenced in medical contexts. A more technical term for it is “postprandial somnolence” which simply means feeling fatigued following a meal.

In the words of Nikolay Kukushkin, a clinical associate professor of life science at New York University, “A food coma is a behavioral response to eating food when the animal, whether it's human or another animal, slows down and relaxes after taking in a meal… Another way to put it is rest and digest.”

Justine Hervé, assistant professor of Economics at the Stevens Institute of Technology provides a more precise definition, stating that “Essentially, it is a reduction in alertness that occurs within one to two hours following the consumption of the meal.”

Scientific Evidence for Food Comas

Hervé and Mani have released research validating that a food coma is not merely a humorous notion we mention after a sizable meal, and demonstrating its concrete impact. Their research involved more than 4,000 students in India participating in various assessments across multiple subjects at different times of the day — some students were given tests shortly after meals, while others undertook assessments several hours later.

Findings indicated that students who undertook examinations within the initial hour following consumption exhibited significantly inferior performance, with Hervé remarking on Gastropod that “Testing in the postprandial period diminished their cognitive ability by 5% to 9% universally across all these categories of tests. "It is a significant decrease in your capacity to execute."

Researchers did consider that students might be exerting less effort on the tests only because they were sleepy after eating. To determine whether or not that was true, they looked at how long students in the postprandial period took to complete an exam, posing the question: Were they not trying as hard because they were tired? However, that was not the situation, and children who had consumed food more recently took, on average, the same amount of time as their counterparts to complete a test.

These findings suggested that a "food coma" is not merely a sensation of fatigue; it also constitutes a cognitive impairment. Twilley articulates on Gastropod that "Subha and Justine assert that those individuals who completed their test within one hour following their meal did indeed put forth their utmost effort. They just didn't have the juice.”