Eating dinner late at night may promote weight gain and impair blood sugar control, according to a recent study presented by the Endocrine Society. With over 2.1 billion adults worldwide classified as overweight or obese, this raises risks for conditions like diabetes and hypertension. Emerging research links later calorie intake to obesity and metabolic syndrome.
“This study illuminates how a late dinner disrupts glucose tolerance and curbs fat burning. Effects vary by individual and bedtime,” explains corresponding author Jonathan C. Jun, M.D., from Johns Hopkins University School of Medicine in Baltimore. “It highlights why some are more susceptible to late eating's downsides. If repeated over time, these metabolic shifts could contribute to diabetes or obesity.”
Researchers examined 20 healthy participants (10 men, 10 women), comparing metabolism after dinners at 10 p.m. versus 6 p.m., with bedtime at 11 p.m. Late dinners resulted in higher blood sugar and reduced fat oxidation from the meal.
“Peak glucose rose about 18% after late dinners, while nighttime fat burning dropped by roughly 10% compared to earlier meals,” notes lead author Chenjuan Gu, M.D., Ph.D., also from Johns Hopkins. “These changes could be even more significant in those with obesity or diabetes.”
This detailed investigation builds on prior findings. Participants used activity trackers, provided hourly blood samples in a lab setting, received sleep and body composition scans, and consumed traceable non-radioactive fats to measure oxidation rates precisely.
“Further research is needed to assess long-term impacts and whether they're driven by post-meal sleep or circadian rhythms,” Jun adds.
