USA: Findings from a 16-week CPNET pilot study revealed the positive impact of a Mediterranean-style dietary pattern, supplemented with whey protein and combined with regular exercise, on blood glucose regulation, body composition metrics, and insulin sensitivity in obese people with prediabetes and type 2 diabetes.
These improvements may be beneficial for the prevention and management of type 2 diabetes mellitus (T2DM) and, thus, preventing the complications associated with T2DM.

"Our findings lend support to using diet- and lifestyle-modification recommendations by healthcare providers as a potential first line of defence against, and as a treatment for, type 2 diabetes," the researchers reported in Medicina.
A Mediterranean-style diet (MSD) is a plant-based diet derived from the populations residing in the regions that border the Mediterranean Sea. An MSD typically consists of a high intake of fruits and nuts, vegetables, legumes, whole grains, legumes, and poultry. Monounsaturated fats from olive oil are the main source of dietary lipids, and alcohol is consumed in low-to-moderate amounts, mainly as red wine. An MSD is typically low in non-fermented dairy products and red meat.
Type 2 diabetes is a chronic condition recognized as the inability to maintain glucose homeostasis, typically presenting with systemic inflammation and insulin resistance. With the increasing prevalence of T2DM and major risk factors, such as prediabetes and obesity, it is crucial to address risk factor reduction strategies.
Performing regular physical activity and adhering to a healthy dietary pattern may provide a strategy for decreasing adiposity, increasing insulin sensitivity, and decreasing the inflammatory response linked with metabolic dysregulation.
Stefani A. Derrick, California Polytechnic State University, San Luis Obispo, CA, USA, and colleagues aimed to investigate the effects of modifications to diet on the markers of inflammation, glycemic control, and body composition in individuals with prediabetes and type 2 diabetes, as well as in healthy individuals.
Secondarily, they aimed to determine which group -- prediabetic, metabolically healthy, or T2DM -- showed the most improvement, and if the improvements in the measured outcomes occurred progressively among the prediabetic, T2DM, and healthy groups, which is pertinent to glycemic control. They hypothesized that a Mediterranean-style diet would improve glycemic control in patients with prediabetes and T2DM.
The CPNET study included twenty-two men and women, overweight-to-obese adults with type 2 diabetes, indicators of prediabetes, or metabolically healthy individuals.
The study's protocol included the daily intake of a high-quality whey protein supplement, following a Mediterranean-style diet, and physical activity recommendations for 16 weeks. The researchers collected fasting blood samples and body composition data at the baseline and following the study. only 13 of the 22 participants who started this study were able to return for the second data collection for study completion after the 16-week interventions. This was due to restrictions associated with the outbreak of the COVID-19 pandemic.
The study led to the following findings:
The prediabetic and T2DM groups exhibited reductions in their fasting plasma glucose (12.0 mg/dL reduction in the prediabetic group; 19.6 mg/dL reduction in the T2DM group) to that of normal and prediabetic levels, respectively, while the T2DM group also demonstrated improvement in their haemoglobin A1c (reduced from 6.8% to 6.0%) to prediabetic levels.
The metabolically healthy, overweight group exhibited significant improvements in adiposity, while the obese prediabetic and T2DM groups showed non-significant improvements in all the measured metrics of body composition.
No significant changes were observed in the inflammatory biomarkers.
"Collectively, our findings suggest that adherence to a nutritious, well-balanced diet and activity may improve the parameters of glycemic control and provide benefits to body composition that help to prevent and manage T2D development," the researchers wrote.
"Our study was able to yield significant findings implying that the effects of a Mediterranean-style diet are seen even for a more conservative sample size," they concluded.
Reference:
Derrick, S. A., Nguyen, S. T., Marthens, J. R., Dambacher, L. L., Sikalidis, A. K., & Reaves, S. K. (2023). A Mediterranean-Style Diet Improves the Parameters for the Management and Prevention of Type 2 Diabetes Mellitus. Medicina, 59(10), 1882. https://doi.org/10.3390/medicina59101882