A small study found that limiting eating hours may improve blood sugar without raising certain serious risks
A six-month study looked at time-restricted eating in adults with Type 1 diabetes and obesity.
Participants who ate only between noon and 8 p.m. saw a greater reduction in HbA1c than those following a daily calorie restriction.
The approach did not appear to increase the risk of severe low or high blood sugar or diabetic ketoacidosis.
Intermittent fasting has become a popular eating strategy, but there are still plenty of questions about whether it is appropriate for people with Type 1 diabetes. A new study from the University of Illinois Chicago offers some early insight.
Researchers found that time-restricted eating a form of intermittent fasting that limits when someone eats rather than what they eat may help adults with Type 1 diabetes improve their blood sugar levels. The study is particularly notable because researchers say it is the first to examine this approach in people with Type 1 diabetes.
This is the first study to examine the effects of intermittent fasting on people with Type 1 diabetes, and the results are extremely promising, researcher Krista Varady, a leading expert on intermittent fasting who conducted some of the first human studies on the subject, said in a news release.
Type 1 diabetes occurs when the body produces little or no insulin. Because managing blood sugar can be complicated for people with the condition, researchers wanted to see whether a specific eating schedule could offer another tool for managing it.
What did the study involve?
The study included 32 adults with Type 1 diabetes who also had obesity. Participants were randomly assigned to one of three groups and followed for six months.
One group practiced time-restricted eating, eating only between noon and 8 p.m. Participants in this group did not have to count calories. Another group followed a traditional calorie-restriction approach, reducing their daily energy intake by 25%. The third group served as a control and did not make changes to their eating habits.
Researchers primarily wanted to determine whether the different approaches affected body weight. They also looked at measures of blood sugar and whether time-restricted eating created safety concerns for people with Type 1 diabetes.
Blood sugar improved, but weight loss wasn't significantly different
After six months, researchers did not find a significant difference in weight loss between the time-restricted eating group, the calorie-restriction group, and the control group. In other words, limiting eating to an eight-hour window did not prove to be a better weight-loss strategy in this study.
There was, however, a notable difference in HbA1c, a blood test that reflects average blood sugar levels over time. The time-restricted eating group experienced a reduction of about 0.5 percentage points compared with the calorie-restriction group.
Researchers also found no significant differences in total insulin use or average glucose levels among the groups.
Importantly, time-restricted eating did not increase the risk of diabetic ketoacidosis, severe hypoglycemia, or severe hyperglycemia during the study. Still, this was a small, early study, and the researchers say larger studies are needed.
This is the first step to showing time-restricted eating could be a safe, potentially effective method for people with Type 1 diabetes to manage their blood sugar levels, Varady said.
Of course, this is just the first step. 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.
Posted: 2026-09-09 16:17:58
