Early dinner may improve blood sugar control, studies find

Eating dinner at least two hours before bedtime may help the body regulate blood sugar more effectively, according to randomized controlled studies in healthy adults. When the same meal was consumed at 6:00 p.m. rather than 10:00 p.m., 24-hour glucose control and next-morning fat metabolism improved, researchers found. The body's insulin response declines naturally over the course of the day, and mealtimes aligned with the biological clock appear to support glucose regulation, the researchers said. In a randomized crossover study of adults with overweight, confining all calories to an 8:00 a.m. to 2:00 p.m. window improved average 24-hour glucose levels and reduced blood sugar fluctuations. An observational study following more than 103,000 adults for an average of 7.3 years reported that having a first meal before 8:00 a.m. and a last meal before 7:00 p.m. could lower long-term risk of developing type 2 diabetes. Smaller studies in patients with type 2 diabetes found that shifting most calories to earlier meals improved daily glucose control and long-term HbA1c readings, while moving dinner from late hours to before 8:00 p.m. produced short-term improvements in fasting glucose and insulin resistance. Researchers emphasized that there is no single ideal mealtime applicable to everyone, but avoiding food close to bedtime may support glucose regulation.