A six-month clinical trial found that time-restricted eating may help adults with Type 1 diabetes manage blood sugar without raising health risks. The study appeared in Diabetes Care.
The work was led by Krista Varady, a professor of kinesiology and nutrition at the University of Illinois Chicago. It marked the first examination of intermittent fasting in people with Type 1 diabetes, a condition that affects less than 1% of the U.S. population and requires lifelong insulin therapy.
Study design and key findings
The trial included 32 participants with Type 1 diabetes who were classified as obese. They were divided into three groups: one followed a time-restricted eating schedule, consuming meals only between noon and 8 p.m. without counting calories; another reduced daily calories by 25%; and a control group made no dietary changes.
After six months, the time-restricted group showed a meaningful drop in blood sugar levels, measured by HbA1c tests, compared to those counting calories. HbA1c levels fell by about 0.5% on average. The trial also recorded no increased risk of severe blood sugar fluctuations or diabetic ketoacidosis, a serious complication.
Varady described the results as encouraging but noted the research was preliminary. “We’ve shown that this eating pattern could be safe and effective for some people with Type 1 diabetes,” she said. “But anyone considering changes should consult their healthcare provider first.”
Broader implications and limitations
While time-restricted eating has become popular for weight loss, its impact on Type 1 diabetes had not been thoroughly tested. The study’s participants came from the Chicago area, which may not reflect broader populations.
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The method could provide an easier option than tracking calories, though the small sample size and short duration mean more research is needed. Varady plans larger trials to see if the benefits extend to diverse groups.
Other studies have looked at how meal timing affects cognitive health. A small pilot presented at Nutrition 2026 suggested time-restricted diets might slightly improve cognition in older women with obesity, though those results remain unconfirmed.
A report in The BMJ found that intermittent fasting may lead to greater weight loss than traditional calorie restriction. However, the outlet noted that without reducing overall intake, the approach does not appear to enhance metabolism or heart health.
For now, the Type 1 diabetes study provides early evidence that time-restricted eating might help some patients. Experts stress that responses vary, and medical guidance is essential when adjusting diets.
New beverage lines are also exploring how dietary timing affects health outcomes.
