Image used for representational purposes only.
London: A recent study by a research team from the University of Surrey in England found that our bodies can predict the timing of regular meals, and the team found that a person's daily blood glucose rhythms may be driven by meal size as well as when it is eaten.
In the first study of its kind, the researchers investigated whether a person's daily regimen anticipates the time of large meals.
Previous studies in this field have focused on animal controls, and to date it has not been determined whether human physiology can predict meal times and food availability.
Jonathan Johnston, Professor of Chronobiology, and Integrative Physiology at the University of Surrey said: "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."
24 male participants conducted an eight-day lab study, with strict sleep-wake schedules, exposure to light-dark cycles, and food intake.
For six days, 12 participants ate small meals every hour throughout the waking period, while the rest of the participants ate two large meals per day (7.5 and 14.5 hours after waking).
After six days, all participants were then put on the same feeding schedule for 37 hours and received small meals hourly in a procedure known to reveal internal circadian rhythms.
Glucose was measured every 15 minutes during the study, and hunger levels were measured hourly during waking hours on days two four and six in the first stage of the study and then hourly for the final 37 hours.
Analyzing results of the first six days of the study, researchers found the glucose concentration of participants in the small meal group increased upon waking and remained elevated throughout the day until declining after their last meal. In the large meal group, there was a similar increase in glucose concentration upon waking however there was a gradual decline leading up to the first meal.
In the final 37 hours, when both groups were fed the same small meals hourly, all participants exhibited an initial rise in glucose concentration upon waking.
However, in those who had previously received two large meals, glucose levels began to decline before the anticipated large meal (which they did not receive) whereas for participants who had always consumed small meals hourly, their glucose levels continued to rise as previously seen.
In addition, in the large meal group, there was an increase in hunger preceding projected mealtimes which sharply declined after the anticipated mealtime had passed.
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."
