In a recent clinical study, researchers found that supplementing combination of trans-resveratrol, a phenol found in several types of plant-based foods, and hesperetin, a flavonone found in citrus fruits, was able to significantly reduce insulin resistance in overweight and obese participants. Insulin resistance, a condition in which glucose can’t enter the cells easily and builds up in the blood, is a key metabolic factor in the pathogenesis of type II diabetes.
 
“Epidemiological studies suggest a diet rich in polyphenols decreases the risk of developing type II diabetes mellitus,” the authors of the study said. “This has led to the evaluation of polyphenol dietary supplements for improvement of metabolic health and improved prevention of T2DM.”
 
In the placebo-controlled, double-blind, crossover study, researchers recruited 29 participants with impaired metabolic health – 9 subjects met the criteria of prediabetes, while 20 participants were highly overweight, 11 of whom were obese. The primary endpoint of the study was insulin sensitivity, which was measured with an oral glucose insulin sensitivity test, as well as oral glucose tolerance tests. The researchers also analyzed potential changes to dysglycemia, blood pressure, dyslipidemia, and low-grade inflammation, all of which are associated with insulin resistance. The participants were administered a once-daily supplement containing 90 mg of trans-resveratrol and 120 mg of hesperetin or a placebo for 8 weeks, before switching over from their respective treatments after a washout period.
 
The authors of the study found that supplementation with the phytonutrient combination was associated with a number of metabolic improvements, with significant reductions being observed in dysglycemia, blood pressure, vascular inflammation and dyslipidemia, “a remarkable multiplicity of pathogenic processes,” the authors of the study said.
 
“Moreover, the health improvement was linked to two established mediators of insulin resistance: TXNIP and TNFa. TXNIP is a mediator of insulin resistance in the liver, skeletal muscle and adipose tissue, and impaired pancreatic beta-cell insulin secretion and TNFa decreases insulin receptor signaling in adipose tissue and skeletal muscle, particularly prior to development of T2DM.”