A new clinical trial indicates that time-restricted eating (TRE), also known as intermittent fasting, can offer significant health benefits to adults suffering from metabolic syndrome. The study, conducted by researchers at the Salk Institute and University of California San Diego School of Medicine, found that adhering to a consistent eight-to-ten-hour eating window each day for three months led to improvements in several markers of blood sugar regulation and metabolic function. These findings, published in the Annals of Internal Medicine, suggest a practical approach to managing a condition affecting over one-third of American adults and significantly raising the risk of heart disease, stroke, and type 2 diabetes.
Study Details and Findings
The TIMET study, a randomized controlled trial, involved 108 adults with metabolic syndrome who were divided into a time-restricted eating group and a control group. Both groups received standard-of-care treatments and nutritional counseling on the Mediterranean diet. However, the TRE group was instructed to consume all their meals within a consistent eight-to-ten-hour window each day, personalized to their individual schedules. Participants logged their meals using the "myCircadianClock" mobile app.
After three months, the TRE group exhibited notable improvements in key markers of cardiometabolic health. Specifically, they showed improvements in blood sugar and cholesterol levels, as well as lower levels of hemoglobin A1c, a marker of long-term blood sugar control. This reduction was similar in scale to what is typically achieved through more intensive interventions by the National Diabetes Prevention Program. Furthermore, the time-restricted eating group experienced a 3–4% greater decrease in body weight, body mass index (BMI), and abdominal trunk fat, without significant loss of lean muscle mass.
Expert Commentary
"Our bodies actually process sugars and fats very differently depending on the time of day," said Satchidananda Panda, a professor at Salk Institute and co-corresponding author of the study. "In time-restricted eating, we are re-engaging the body's natural wisdom and harnessing its daily rhythms to restore metabolism and improve health."
Pam Taub, professor of medicine at the UC San Diego School of Medicine and a cardiologist, emphasized the urgent need for effective lifestyle interventions. "For many patients, metabolic syndrome is the tipping point that leads to serious and chronic diseases like diabetes and heart disease," she stated. "There is an urgent need for more effective lifestyle interventions that are accessible, affordable, and sustainable for the average American."
Implications for Treatment
The study highlights the potential of time-restricted eating as a practical and accessible intervention for managing metabolic syndrome. Unlike expensive pharmaceuticals, TRE is a simple lifestyle change that doesn't cause side effects and can be maintained indefinitely. Emily Manoogian, a staff scientist in Panda's lab at Salk and first author of the study, noted, "Patients appreciate that they don't have to change 'what' they eat, just 'when' they eat."
The researchers suggest that healthcare providers could consider recommending TRE to patients with metabolic syndrome as a complement to existing treatments. However, they also acknowledge the need for additional long-term studies to determine whether time-restricted eating can sustain these benefits and ultimately reduce the risk of chronic disease.
Metabolic Syndrome Context
Metabolic syndrome is characterized by a cluster of conditions, including high blood pressure, elevated blood sugar, excess abdominal fat, and abnormal cholesterol levels. Western diets high in sugar, salt, and fat, combined with increasingly sedentary lifestyles, are significant contributors. While initial recommendations often focus on eating less and moving more, these lifestyle changes are difficult for many people to sustain long-term, making TRE a potentially valuable alternative.
