Eating Only 8 Hours a Day May Help Control Type 1 Diabetes, Study Suggests

A new study from the University of Illinois Chicago (UIC) suggests that time-restricted eating — limiting food intake to a set window each day — could help adults with Type 1 diabetes control blood sugar. The research was led by Krista Varady, a UIC professor of kinesiology and nutrition who has long studied intermittent fasting; she called it the first study to examine intermittent fasting in people with Type 1 diabetes, and said the results were "extremely promising."

Type 1 diabetes is a chronic condition in which the body produces little or no insulin, the hormone that moves glucose into cells; it affects less than 1% of people in the U.S. Varady's participants were classified as obese under Centers for Disease Control and Prevention body mass index guidelines, a combination she said applies to about 0.5% of the U.S. population. Researchers enrolled 32 Chicago-area participants, randomly split into three six-month groups: one ate only between noon and 8 p.m. without counting calories, another cut calories by 25%, and a control group made no changes.

After six months, the time-restricted eating group showed better blood sugar results than the calorie-reduction group. HbA1c, a blood test reflecting average blood sugar over several months, fell by about 0.5% on average in the time-restricted group. Researchers found no increase in dangerously high or low blood sugar risk, and no added risk of diabetic ketoacidosis, a potentially life-threatening condition from insufficient insulin.

Varady cautioned that this is only a first step, and should not prompt anyone with Type 1 diabetes to change eating habits without medical guidance. "Anyone making changes to their eating habits, especially those with diabetes, must work closely with their endocrinologist or healthcare provider to find a solution that works for them," she said. She next hopes to conduct larger studies across multiple research sites to determine whether the findings hold true in a broader population.