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When you eat might not seem nearly as important as what you eat. And while a balanced, healthy diet is absolutely key, increasingly more evidence is showing that the timing of your meals matters, too. Whether you’re keeping an eye on the clock for your intermittent fasting schedule or are hoping to reduce your odds of developing diabetes, when you eat can make a difference for your health.
Adjusting the timing of your meals, especially if you’re someone who eats meals at night – after typical dinner hours – may have a positive impact on your natural blood glucose control. And that can potentially help you decrease your risk for health concerns like diabetes, heart disease and obesity.
If you’re hoping to keep your health (and your glucose levels) in check, here’s what science says about timing your meals.
Eating meals throughout the night throws off your circadian rhythm
A small clinical trial supported by the National Institutes of Health examined the impact of meal timing on individuals’ blood glucose levels. The researchers set out to determine how eating during the night affects glucose, in comparison to eating during the day. They examined 19 healthy participants, who were each randomly assigned to 14 days of eating on either a nighttime meal schedule or a daytime meal schedule.
Researchers then studied the impact of each meal schedule on the participants’ circadian rhythms. Those who ate their meals at night saw increases in their blood glucose levels, with glucose rising by approximately 6.4 percent compared to daytime eaters. Participants who stuck to typical daytime meals saw no significant increases.
These findings suggest that sticking solely to daytime meals can help keep glucose levels under control. Those who eat their main meals throughout the night, such as those who work night shifts, may see an unexpected increase in blood glucose.
Why, exactly, did eating at night throw off the participants’ blood glucose levels? Your circadian rhythm regulates not only your sleep-wake cycle, but also many other bodily functions – including your metabolism. And the study’s researchers hypothesize that the circadian rhythm becomes out of sync when you’re performing daytime activities (like working and eating your primary meals) during nighttime hours, then sleeping during the day.
When your circadian rhythms get out of whack, or off-kilter from their natural patterns, your brain and your behavioral cycles struggle to synchronize. It messes with natural processes within the body, and it can alter when certain chemicals, hormones and other changes occur. And all of this funky misalignment can lead to higher-than-typical glucose.
Why better blood glucose control matters for your health
Keeping your glucose levels top of mind likely isn’t a daily concern for you, unless you’re living with prediabetes or diabetes. But glucose matters for everyone, especially if you’re hoping to stay as healthy as can be.
Research suggests that getting your glucose in check is important in lowering your risk for ailments like type 2 diabetes and certain types of cancer, in connection with obesity. Achieving better glucose control may potentially lower an individual’s cancer risk by as much as 60 percent.
And, since blood glucose levels can be tied to type 2 diabetes and unhealthy weight gain, there are even more reasons to keep an eye on how much they’re spiking.
What you can do to keep glucose under control
If you’re already eating your daily meals on a typical schedule (during the day, that is), then there’s good news. You likely aren’t experiencing an increase in your glucose levels overall. However, as the clinical trial noted, those who operate on opposite schedules and go about their days during evening hours may be most at risk for an increase.
So, what can you do if you work at night and eat your primary meals in the evening? You don’t necessarily need to flip or uproot your entire lifestyle. The study’s researchers suggest trying to schedule your meals so they’re as in tune with your natural circadian rhythm as much as possible. You can try to time your meals so they occur during typical times, like eating your first meal around dinner time and your “dinner” in the morning. Opting for smaller, more frequent meals rather than a few large meals may also help.
But, most importantly, if you’re concerned about your blood glucose levels and meal timing, check in with your doctor. You can address your specific risk level and work to develop an eating plan that works for you – and helps you work with your unique needs.
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