Category: Diabetes Management, Ketogenic Diet, Mediterranean Diet
A recent study by Stanford Medicine reveals that both ketogenic and Mediterranean diets are effective in controlling blood glucose levels for people with Type 2 diabetes or those at risk of developing the disease. However, the Mediterranean diet, with its emphasis on vegetables, legumes, fruits, whole grains, olive oil, and fish, proves to be more sustainable and easier to maintain in the long run.
The trial, published in the American Journal of Clinical Nutrition, compared the two popular low-carb diets in terms of blood glucose control, cardiometabolic risk factors, weight loss, nutrition, and adherence. While both diets helped control blood glucose levels and facilitate weight loss, the ketogenic diet was found to be lacking in several essential nutrients, such as fiber, thiamin, vitamins B6, C, D, and E, and phosphorus. Participants in the study also found the ketogenic diet more challenging to stick to over time.
Lead author of the study, Christopher Gardner, PhD, expressed concerns about the ultra-low-carb ketogenic diet, which eliminates nutrient-dense food groups like legumes, fruits, and whole grains. The study involved 40 adults with Type 2 diabetes or prediabetes, who tried both diets for 12 weeks each. Researchers collected blood samples to evaluate blood glucose control, lipid control, body weight, and other clinical measures while also interviewing participants about their adherence and satisfaction with the diets.
Both diets improved blood glucose control, with HbA1c levels dropping similarly in both (9% on keto and 7% on Mediterranean). Weight loss results were also comparable (8% on keto and 7% on Mediterranean), as were improvements in fasting insulin and glucose, HDL cholesterol, and liver enzyme ALT. LDL cholesterol increased on the keto diet and decreased on the Mediterranean diet, while triglycerides decreased more on the keto diet.
Participants adhered to both diets relatively well when provided with ready-to-eat food, but adherence dropped when they had to prepare their own meals. Interestingly, three months after the trial, participants had maintained lower blood glucose levels and weight loss, but were eating closer to a Mediterranean diet than a keto diet.
The study concluded that the less restrictive Mediterranean diet was just as effective in controlling glucose and more sustainable. Gardner emphasized the importance of restricting added sugars and refined grains, and including non-starchy vegetables in the diet, rather than restricting heart-healthy, quality carbohydrate foods.