Effect of keto and Mediterranean diets on glucose control compared

Christopher D. Gardner, Ph.D., from Stanford University in California, and colleagues performed a small randomized, crossover trial to compare two low-carbohydrate diets with three key similarities (incorporating nonstarchy vegetables and avoiding added sugars and refined grains) and three key differences (incorporating versus avoiding legumes, fruits, and whole, intact grains) for their effects on glucose control and cardiometabolic risk factors among 33 individuals with prediabetes or type 2 diabetes.

The researchers reported that glycated hemoglobin values did not differ between diets at 12 weeks. There was a greater decrease observed in triglycerides with the well-formulated ketogenic diet (WFKD; −16 percent) versus the Mediterranean-plus diet (Med-Plus; −5 percent). Low-density lipoprotein cholesterol was higher for the WFKD (+10 percent) versus Med-Plus (−5 percent); high-density lipoprotein cholesterol increased 11 and 7 percent, respectively. Weight decreased 8 and 7 percent, respectively; however, there was a significant interaction seen for diet × order. While on the WFKD, participants had lower intakes of fiber and three nutrients versus the Med-Plus. Follow-up data suggest the Med-Plus is more sustainable.

“Restricting added sugars and refined grains and emphasizing the inclusion of vegetables should be the focus,” Gardner said in a statement. “There’s no reason to restrict heart-healthy, quality carbohydrate foods above and beyond.”