L’ESSENTIEL
- Selon une nouvelle étude, dîner trois heures avant de se coucher prolonge le jeûne nocturne et améliore certains marqueurs cardiovasculaires et métaboliques.
- Après 7,5 semaines à ce rythme, les participants ont montré une baisse de leur tension artérielle et de leur fréquence cardiaque pendant la nuit.
- Ils avaient aussi un meilleur contrôle de la glycémie en journée, car leur pancréas a régulé la glycémie plus efficacement, en libérant suffisamment d’insuline au bon moment.
Adjusting dinner time could offer a simple way to improve heart and metabolic health, according to fresh research.
Prolonged Overnight Fasting Between 13 and 16 Hours
Researchers at Northwestern Medicine investigated the impact of extending the overnight fasting period by having participants finish meals three hours before bedtime. The study, published in Arteriosclerosis, Thrombosis, and Vascular Biology, suggests aligning eating patterns with the body’s natural sleep-wake cycle may have benefits.
“Adapting our eating schedule to align with our body’s natural rhythms—the circadian rhythm—may improve coordination between the heart, metabolism, and sleep, all of which contribute to cardiovascular health”, said Dr. Daniela Grimaldi, the study’s first author, in a statement.
The research team followed 39 adults between the ages of 36 and 75 who were overweight or obese for 7.5 weeks. Participants were divided into two groups: one group stopped eating three hours before bed, while the control group maintained their usual dinner times. This resulted in fasting windows ranging from 13 to 16 hours for the early-dinner group and 11 to 13 hours for the control group.
After eating, all participants dimmed the lights for three hours before going to bed.
Lower Blood Pressure and Heart Rate
After 7.5 weeks, the group that ate dinner earlier experienced several positive changes, including:
- a 3.5% decrease in nighttime blood pressure;
- a 5% reduction in nighttime heart rate;
- improved daytime blood sugar control, as the pancreas regulated glucose more effectively by releasing sufficient insulin at the appropriate times.
“It’s not just what and how much we eat, but when we eat in relation to sleep that’s crucial for reaping the physiological benefits of food”, explained Dr. Phyllis Zee, the study’s lead author.
These findings build on previous recommendations. In 2024, the French National Agency for Food, Environmental and Occupational Health Safety (Anses) too advised eating dinner early—at least two hours before bedtime—to extend the overnight fasting period, as outlined in their publication. The agency also recommended prioritizing breakfast and reducing calorie intake in the evening.
