Study Reveals Comparative Effectiveness of Dietary Interventions for Type 2 Diabetes and Obesity Management

Various dietary approaches, including intermittent energy restriction (IER), time-restricted eating (TRE), and continuous energy restriction (CER), are all effective in improving blood sugar levels and promoting weight loss in individuals with type 2 diabetes (T2D) and obesity. The study authors, who presented their findings at the Endocrine Society’s 2025 annual meeting, noted that the current research is the first to compare the effects of 3 different dietary interventions.¹

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Obesity and Type 2 Diabetes

The risk of T2D rises with the increase of body weight, as obesity and a lack of physical exercise are known to worsen insulin resistance. This resistance is a component in developing T2D. According to the Obesity Action Coalition, the occurrence of T2D is 3 to 7 times higher in those who experience obesity compared to those at a normal weight. Following, the prevalence is 20 times more likely in individuals with a body mass index (BMI) greater than 35 kg. However, the location of the excess fat deposited in the body is also important in determining the risk and severity of T2D.²

Weight loss is a crucial objective for individuals with excess weight or obesity, especially those with T2D, as a moderate and sustained reduction of 5% to 10% of body weight can enhance insulin sensitivity, lower fasting glucose, and potentially decrease the need for diabetes medications. While diet, exercise, and behavior modification effectively treat obesity, pharmacotherapy or surgery may also be necessary for some patients.²

Clinical Data Research and Evidence

Researchers included 90 patients in their single-center, randomized, parallel-controlled trial conducted at the First Affiliated Hospital of Zhengzhou University from November 19, 2021, to November 7, 2024. Among the total number of individuals included, 63 completed the study—18 females and 45 males with an average age of 36.8 years, a mean diabetes duration of 1.5 years, a baseline BMI of 31.7 kg, and a hemoglobin A_1C (HbA_1C) of 7.42%. The participants were randomly assigned in a 1:1:1 ratio to either the IER, TRE, or CER group, with a weekly caloric intake that was supervised by nutritionists for 16 weeks.¹

The results demonstrated that while all groups showed no significant differences in HbA_1C reduction and weight loss at the end of the study, the IER group exhibited the greatest absolute decreases in both. Compared to TRE and CER, IER significantly improved fasting blood glucose and triglycerides and increased the Matsuda index, which indicates better whole-body insulin sensitivity, with no significant changes in uric acid or liver enzymes across any group.¹

Further results found that mild hypoglycemia occurred in 2 patients in both the IER and TRE groups and 3 in the CER group. The IER group demonstrated the highest adherence at 85%, followed by CER at 84% and TRE at 78%, with IER and CER significantly outperforming TRE.¹

The findings suggest that the results emphasize the feasibility and effectiveness of dietary interventions for individuals that experience obesity and T2D.¹

“The research fills a gap in directly comparing 5:2 intermittent energy restriction with 10-hour time-restricted eating in patients with obesity and type 2 diabetes. The findings provide scientific evidence for clinicians to choose appropriate dietary strategies when treating such patients,” Haohao Zhang, Ph.D., chief physician at The First Affiliated Hospital of Zhengzhou University in Zhengzhou, China, said in the news release.¹

REFERENCES

1. Intermittent energy restriction may improve outcomes in people with obesity and type 2 diabetes. EuerkAlert!. News release. July 13, 2025. Accessed July 20, 2025. https://www.eurekalert.org/news-releases/1090229

2. Rogers, J. Z., & Still, C. D. (2005). Obesity and type 2 diabetes. Obesity Action Coalition. https://www.obesityaction.org/resources/obesity-and-type-2-diabetes/