🕒 The surprising link between late meals, health, and weight gain

Snacking in the evening or eating dinner too late may not only disrupt sleep. A recent study reveals that meal timing has a direct impact on our metabolism, particularly on blood sugar management.


Our body follows a circadian rhythm, an internal clock that regulates biological functions over 24 hours. This rhythm notably influences how we metabolize glucose. According to research by Olga Ramich and her team, eating earlier in the day could improve insulin sensitivity, a key hormone in blood sugar regulation.

To understand this link, researchers analyzed the habits of twins, which helps distinguish genetic effects from environmental ones. The result: up to 60% of eating behaviors may be linked to genetics. Some people might therefore be naturally more inclined to eat late—a behavior associated with an increased metabolic risk.

The study also introduces a new indicator: the "circadian calorie noon," the time of day when 50% of daily calories have been consumed. In people who reach this threshold later, insulin sensitivity is lower, which could increase the risk of developing diabetes.

These findings pave the way for more personalized nutrition recommendations. However, changing meal times isn't always easy, especially when our habits are influenced by genetics or lifestyle.

What is the circadian rhythm?

The circadian rhythm is our internal biological clock, set to a 24-hour cycle. It influences sleep, body temperature, hormone production... and metabolism.

This rhythm is controlled by a small region of the brain, the suprachiasmatic nucleus, which primarily responds to light. When this rhythm is disrupted—due to night shifts, jet lag, or irregular meal times—negative health effects can arise, particularly in glucose regulation.

What's the link between insulin and metabolism?

Insulin is a hormone that allows glucose (sugar) to enter our cells, where it is used as an energy source. During a meal, blood glucose levels rise, and insulin acts to regulate them.

When cells become less sensitive to insulin—a phenomenon called insulin resistance—glucose accumulates in the blood, which can lead to type 2 diabetes.

Better synchronizing our meals with our biological rhythm could therefore be an effective lever for improving metabolic health, especially in at-risk individuals.