Short for the less palatable term “ni**eritis,” the term is used in both the United States and Caribbean to describe the routine of becoming sleepy after eating a large meal.
“The itis” is jokingly said to affect blacks more than any other group. The term also implies that the person who has “the itis” is lazy, and often too fatigued to return to work after their mid-day meal.
So is it fact or fiction?
It depends.
“All of us are sleepier during early to mid-afternoon,” says Dr. Mark Mahowald, former director of the Sleep Disorders Center at Hennepin Medical Center, and now a professor of neurology at University of Minnesota Medical School. “There is no racial difference in the sleepiness we all experience.”
Most humans have their body clocks set to become sleepier between midnight and 6:00 am, and again around noon. Many people erroneously attribute this mid-day sleepiness to their big lunch, sitting in a dark room, hot weather, or a boring meeting.
However, these things do not cause sleepiness or “the itis,” they simply bring out the mild sleepiness that was already there from their intrinsic body clocks.
“This is why cultures wiser than ours have picked that time for their siesta [or nap] time,” says Mahowald.
Small studies have shown increased sleepiness after eating meals high in carbohydrates or high in fats, but others show no effect.
So where did the “itis” notion come from?
One theory is that, given the predisposition for sleepiness during those times, that any group of people that are also exposed to the heat after eating a large lunch, without taking a nap is set up for “the itis,” so to speak, says Mahowald.
The fact that both now, and decades ago, blacks in the United States and the Caribbean have been overrepresented in outdoors work during warmer climates, makes this theory a strong possibility.
In a subset of African-Americans, a condition called obstructive sleep apnea could play a role. Overall, it tends to affect people who are obese, but African-Americans are more affected despite body habitus. People with obstructive sleep apnea stop breathing several times during sleep, for seconds at a time, usually due to obstruction from the tongue, fat around the neck, or in the case of many African-Americans, the natural construct of their airways – the nose, throat or adenoids.
Because of the lack of restful sleep, people with this condition are often sleepy during the day. This also increases the risk of decreased alertness in the setting of the other factors already mentioned.
Conclusion: Since all people technically get “the itis,” the myth is somewhat true. But, since it doesn’t affect blacks more than other groups as the stereotype says, that makes it fiction.