Eating regularly is crucial to our health. Some folks eat right as the wait and other gorge after a long day. A new study by the University of Surrey suggests our human bodies are able to predict mealtimes.
The research team suggests our bodies can predict mealtimes and that meal size can influence daily blood sugar patterns and meal timing. The University of Surrey research team, led by Professor Jonathan Johnston, Ph.D., first studied if our human circadian rhythm can predict large meals.
Per the National Institute of General Medical Sciences, circadian rhythms are natural cycles that follow a 24-hour period, involving physical, mental, and behavioral variations. They react mostly to light and dark cycles, allowing us to wake up in the morning and sleep at night.
They are generally in sync with environmental cues like light/dark cycles. Prior research in the field centered on animals and is now focusing on human physiology and its ability to anticipate mealtimes.
"We often get hungry around the same time every day, but the extent to which our biology can anticipate mealtimes is unknown. It is possible that metabolic rhythms align to meal patterns and that regularity of meals will ensure that we eat at the time when our bodies are best adapted to deal with them," shared Johnston.
How was the study conducted?
In the study, 24 male participants engaged in eight days of laboratory research accompanied by precise sleep schedules, exposure to light/dark cycles, and meal times. For the first six days, 12 participants took small amounts of food every hour after waking up. The remaining half ate two large daily meals, precisely 7.5 and 14.5 hours after waking up.
Following six days, every participant stuck to the same eating schedule for 37 hours and ate small meals hourly to disclose internal circadian rhythms. The study measured their glucose level every 15 minutes, and levels of hunger were calculated every hour while they were awake on days two, four, and six, and then hourly for the concluding 37 hours.
The eight-day study displayed that glucose concentration in the hourly small meal group heightened once waking up, and stayed high throughout the day before diminishing at the end of their last meal.
In the other group, a comparable increase in glucose concentration was visible once waking up, but a moderate reduction led to the first meal. During the concluding 37 hours, when both groups ate small meals every hour, everyone showed increased glucose concentration when waking up. Despite the increase, the group with two large meals per day began displaying a decrease in glucose levels around their usual large meal time.
They also saw a growth in hunger when nearing their usual mealtime, which intensely diminished once their anticipated mealtime elapsed.
Professor Johnston concluded: "What we have found is that the human body is rhythmically programmed to anticipate mealtimes particularly when food is not readily accessible. This suggests that there is a physiological drive for some people to eat at certain times as their body has been trained to expect food rather than it just being a psychological habit."
- Current Biology - Cell Press. Human glucose rhythms and subjective hunger anticipate meal timing
- National Institute of General Medical Sciences. Circadian Rhythms