Modern food science is increasingly finding that when we eat is as important as what and how much we eat and the findings often defy what seems to be common sense. One such example is the belly-expanding consequence of skipping meals.

Martha Belury, a professor of human nutrition at Ohio State University, discovered skipped meals send the wrong signals to the body and may do more harm than good, as far as weight loss is concerned. She and her research team compared results of two groups of mice: the control group enjoyed unlimited access to each day’s supply of food but the study group’s food supply began as only half that of the control group.

For three days, the mice in the study group were fed half the calories the freely eating control group was given; this caloric restriction was meant to mimic skipped meals for humans. For three days following caloric restriction, the study group of mice were gradually fed a little more each day until, on day six, their caloric intake was the same as the control group.

Lost Weight Re-Gained

The mice on the restricted diet did lose weight, initially, but gained it back as their food supply was increased. Many humans find the same yo-yo effect happening during and after a severely restrictive weight-loss diet.

Gorging and Fasting

The study mice also developed a habit of gorging themselves with a full day’s supply of food in about four hours time, leaving nothing for them to eat the remaining 20 hours. Belury likens this cycle of gorging and fasting to humans eating just one large meal a day.

Insulin Resistance

Upon further investigation, Belury’s team discovered the study group had developed insulin resistance, a risk factor for type 2 diabetes. In a healthy mouse or human, the liver secretes glucose (the form of sugar the body uses for cellular energy) into the bloodstream when insulin levels are low, such as during sleep. After a meal, the pancreas does two things: it signals the liver to cease glucose production and it secretes insulin to remove the meal’s sugar supply from the blood and into the cells, where it is used for energy.

When meals are skipped, as with the gorging-fasting mice, the liver doesn’t get the signal to stop glucose production. The abundance of sugar in the bloodstream, from both the meal and the now-overproducing liver, cannot be transferred effectively into cellular energy and all the excess sugar is stored as fat. Over time, the liver becomes resistant to the beneficial insulin produced by the pancreas, secretes non-stop glucose, and diabetes develops.

Activation of Fat-Storing Genes

Also, certain genes that promote fat storage and fatter fat cells were activated in the gorging-fasting mice. These same genes promoted the storage of abdominal fat, expanding the bellies of the study mice while the control group, which nibbled all day long, remained slim and healthy. The study group was also found to have higher levels of inflammation than the control group had.

While the study was conducted on mice, it is quite likely similar effects happen when humans skip meals, too: inflammation increases, the liver misses signals from the pancreas, and excess sugar is stored as bigger fat cells right around the waistline, where most people want to lose the most weight. If skipped meals become the habit, insulin resistance is likely to develop, setting the stage for diabetes to begin. Nibbling or eating small meals over the course of the day may prove to be the more effective and healthier approach to weight loss and long-term weight maintenance.

Sources:

  1. Belury, Martha A, et al. "Short-term food restriction followed by controlled refeeding promotes gorging behavior, enhances fat deposition, and diminishes insulin sensitivity in mice." JNB / The Journal of Nutritional Biochemistry. Elsevier Inc., 14 Mar. 2015. Web. 29 May 2015.
  2. "Insulin Resistance and Prediabetes." National Diabetes Information Clearinghouse (NDIC). US Department of Health and Human Services, n.d. Web. 29 May 2015.