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New research shows that TRE may have positive effects on blood sugar and fat loss. Tanya Yatsenko/Stocksy
  • Time-restricted eating (TRE) is a type of fasting that involves eating within a certain time window.
  • Researchers recently found that time-restricted eating (TRE), combined with standard nutritional counseling, can help improve glucose control and weight loss among adults with metabolic syndrome.
  • Compared to people who followed standard dietary guidance alone, people who engaged in TRE experienced greater reductions in fat mass and hemoglobin A1C (HbA1c) levels.

Researchers from the Salk Institute for Biological Studies and the University of California San Diego have found that time-restricted eating (TRE), combined with standard nutritional counseling, led to modest improvements in glucose control and weight loss among adults with metabolic syndrome.

The randomized controlled trial involved 108 participants and tracked their eating habits through the myCircadianClock (mCC) app.

Results showed that the TRE group experienced greater reductions in fat mass and improvements in glucose control compared to those who followed standard dietary guidance alone.

This new research, published in the Annals of Internal Medicine, assessed the impact of time-restricted eating (TRE) on glucose regulation, fat mass, and weight loss in adults with metabolic syndrome.

Metabolic syndrome is not a distinct condition; rather, it includes a collection of risk factors that are associated with an increased likelihood of developing type 2 diabetes, cardiovascular disease, and high cholesterol.

This study aimed to evaluate the effectiveness of personalized TRE as a lifestyle intervention, in addition to standard nutritional counseling.

The findings indicated that TRE, combined with standard nutritional counseling, resulted in modestly greater improvements in glucose control and reductions in weight and fat mass compared to standard nutritional counseling alone.

Time-restricted eating (TRE), commonly seen in intermittent fasting, is gaining popularity as a method for weight management. The most prevalent approach involves consuming food within an 8 to 12-hour window each day, while fasting outside that period, allowing only water and calorie-free beverages.

Previous research suggests that TRE may provide several health benefits. These include weight loss, particularly for individuals with overweight or obesity, as well as improved cholesterol and triglyceride levels, which may reduce the risk of cardiovascular disease.

Other potential benefits include enhanced cognitive function, anti-aging and anti-cancer effects, and improved insulin sensitivity.

Participants were randomly divided into two groups; the first group received healthy lifestyle and nutritional advice, such as following the Mediterranean diet. They were instructed to maintain their usual eating patterns and any prescribed medications.

The second group received the same nutritional guidance but was also instructed to follow a personalised 8 to 10-hour eating window.

Researchers remotely tracked the intervention over a three-month period. During this time, participants used the myCircadianClock (mCC) app to log their meal times daily.

The main focus of the study was changes in fasting blood glucose and HbA1c levels.

HbA1c is a blood test that shows your average blood sugar levels over the past 2-3 months to help monitor or diagnose diabetes.

Secondary outcomes included other cardiometabolic health markers, such as low-density lipoprotein (LDL) and high-density lipoprotein (HDL) cholesterol, triglycerides, C-reactive protein, and abdominal fat mass.

The results showed that, compared to the group receiving only standard nutritional guidance, the TRE group experienced a greater reduction in weight, with a larger proportion of the weight loss coming from fat.

This suggests that TRE may reduce the risk of muscle loss typically associated with weight loss.

Although the changes were modest, the TRE group also saw greater improvements in blood sugar control and hemoglobin A1c levels.

These data suggests that TRE is an effective and practical lifestyle intervention with positive impacts on glycemic control and cardiometabolic health.

First author Emily N C Manoogian, PhD, postdoctoral researcher at the Salk Institute for Biological Studies, explained the key findings to Medical News Today.

“Metabolic syndrome is a combination of cardiovascular risk factors and there is no one treatment to cure it. In adults with metabolic syndrome, we found that TRE was safe, even when combined with common medications such as Metformin and Statins, and provided benefits to multiple aspects of this complex syndrome including HbA1c (blood sugar), LDL cholesterol, and body composition (loss of fat while maintaining lean mass).”
— Emily N C Manoogian, PhD

“This is the same amount achieved in the Diabetes Prevention Program, leading to a 58% decrease in Type 2 Diabetes 2.8 years later,” Manoogian added.

“Notably, about 70% of participants were already on medications to improve their cholesterol, so we saw an additive effect.”

Mir B Ali, MD, board certified bariatric surgeon and medical director of Memorial Care Surgical Weight Loss Center at Orange Coast Medical Center in Fountain Valley, CA, not involved in the study, told MNT that the research is “consistent with other studies that have shown a benefit to intermittent fasting/time-restricted eating.”

“As people are more aware of time restricted eating, more people can potentially employ this approach to help lose weight. Of course, choosing the right foods is the most important thing for weight loss, but by fasting for a period of time, it directs the body towards burning fat. Typically there is a window of 8-16 hour, where you are not consuming calories, but calorie free fluids are ok. For most people, it is easiest to do part of this period at night as you will be sleeping for a good part of the time period.”
— Mir B Ali, MD

Manoogian also explained that “this research demonstrates that 8-10 hour TRE is an effective lifestyle intervention that can be combined with medications to improve multiple aspects of cardiometabolic health, specifically glucose regulation, cholesterol, and weight.”

“Additional studies, that are longer duration, have more participants, and run at multiple locations, need to be done to better understand the health impacts of TRE,” Manoogian highlighted.

While more research is needed, the study adds to the growing body of research on TRE and metabolic syndromes.

In addition, the innovative use of the myCircadianClock (mCC) app opens the door for future studies to be conducted remotely and on a larger scale.