We are increasingly learning a lot about the body’s circadian rhythm and how it helps dictate our health. A new study shows that living against the clock, like working night shifts and eating at strange times, can come with real health risks.
Researchers have newfound evidence to explain why it’s not just what we eat that matters, but when we eat that can affect obesity, metabolic syndrome and diabetes.
Secreted by the pancreas and critical in preventing diabetes, insulin levels rise and fall within a 24-hour circadian rhythm. The new study went on to find that mice, unable to tell the time of day, tended to have higher risks for insulin resistance and obesity.
The researchers measured insulin levels in mice at different hours, and doing so revealed a regular pattern. Normal mice become insulin resistant during the day (when they typically sleep) and mice unable to keep the time lost this rhythm and also put on more weight when fed high-fat food.
That insulin responses fluctuate throughout a 24-hour period is a relatively new concept. There is a rhythm, with daytime and nighttime, which keeps us balanced. Within that rhythm, insulin action and blood sugar metabolism are tied to the time of day and to the internal mechanisms that keep track of that time. This can be at odds with the modern world, where our schedules might change, food is always around, and we don’t have to rely on darkness and sunlight to govern our movements.
The researchers say that following a healthy diet, like the Mediterranean diet, where the main meal is consumed in the middle of the day, is the best approach. That, too, makes sense, as a dense supper that ends at 8 p.m. is close to the time when our body begins shutting down for the day. They believe light suppers are ideal, and after-dinner snacking should be avoided. That’s because the body wants to slow down its insulin release, but there we are swallowing a bucket of popcorn during a late movie, or heading to the fridge for leftovers from dinner to satisfy a 10 p.m. craving.
Those cravings are not your body’s way of saying it is hungry. They are completely mental. The body wants to rest and rejuvenate—as proven through insulin and blood sugar levels that slow down later in the day.
A good approach to dieting could be to focus on when you eat, as much as what you eat.
Sources for Today’s Articles:
What “Living Against the Clock” Can Do to Your Health
Shi, S., et al., “Circadian disruption leads to insulin resistance and obesity,” Current Biology; published online February 21, 2013.