How ‘eating jet lag’ messes with your health every Monday

As soon as it hits 5 p.m. on Friday, the rigid rules of the work week are thrown out the window. No more self-imposed curfew to make sure you get up in time for work. No more meal prepping. Weekends are for fun, not guidelines. But on Monday, you pay the price.

Not to be a total buzzkill, but as you can imagine, going off the rails on the weekend comes with a catch. According to a new study from the University of Barcelona, published in the science journal Nutrients, many tend to eat irregularly on the weekends, varying the time to eat instead of the set meal times they tend to stick to during the week. This, researchers say, causes what they call “eating jet lag,” creating an imbalance between your biological clock and nutrition.

According to the study, when food is eaten at unusual hours, nutrients aren’t metabolized as efficiently. This may be one reason why people who have unusual work schedules are at a greater risk for gaining weight and developing other health problems. “Eating late at night can have significant metabolic effects,” says Casey Means, MD. She explains that melatonin—which is secreted at night—can negatively impact insulin levels. “This is why, in studies, identical meals eaten at night—when melatonin is in higher concentrations—versus in the morning have very different glucose responses, with higher glucose responses at night.”

Beyond the time to eat, double board certified functional integrative doctor Bindiya Gandhi, MD says many people change what to eat on the weekends, too, which can affect sleep and energy levels negatively. “Many people tend to eat less nutrient-rich foods on the weekends mainly because they’re eating out and engaging in more social events. Gravitating toward sugary or salty foods can impact cortisol production, which in turn negatively affects sleep,” she says, adding that increased alcohol consumption can also negatively impact the REM cycle.

How to practice intuitive eating:

“Research has also shown that higher saturated fat, high in sugar, and lower in fiber may produce less slow wave sleep, more nighttime arousals, and a reduction in overall sleep quality,” says Casey Means, MD. “Unfortunately, weekend foods like typical brunches of pancakes, waffles, butter, and and dinners out with sugary drinks, burgers, fried foods, and desserts, all fit the bill of foods that are going to negatively impact sleep quality.”

All of this can be bad news for your energy levels, too. Have you ever made mental plans to do all sorts of fun activities for Saturday and Sunday only to be too tired to do anything once the time comes? An interrupted sleep cycle due to a change in eating habits could be why. Meals high in refined sugar or refined carbohydrates can cause glucose levels to spike and then drop, says Dr. Means

Consistency (both in terms of when and what you eat) is key to maintaining good energy levels, sleep, and overall health, says Dr. Gandhi. Ensuring that you aren’t living a life of deprivation during the week will mean you’ll be less likely to go off the deep end on the weekends. As with most things, it’s all about balance.

These matcha pancakes are both healthy and decadent—perfect for a weekend breakfast. Plus, why some healthy eating experts advocate making breakfast the biggest meal of the day, whether it’s the weekend or not.