When it comes to lowering blood sugar and losing weight, which diet works best? According to a recent study from Stanford University, when dieters were given either the Mediterranean or the Keto diet, each one works as well as the other for controlling blood sugar and ultimately helping people achieve their weight loss goals. But the more restrictive Keto diet is harder to sustain, so ultimately, the doctor who authored the study concluded, that a mostly plant-based diet wins for long-term weight loss since it is easier to follow and sustain than a low-carb diet.
A previous study found that to be even healthier, doing a "Green Mediterranean diet" that is focused on high-fiber plant-based foods and removes most animal products has proven to be more heart-healthy than a Mediterranean diet that still allows cheese and small amounts of meat.
In yet another study, which showed plant-based diets are effective for weight loss when participants added more legumes to their plate they lost even more weight than dieters who didn't eat as many legumes. So the scientific evidence points to plant-based diets as the most effective in both lowering blood sugar and promoting healthy, lasting weight loss.

Keto Diet Not Better for Blood Sugar than Mediterranean Diet, Study Finds

This latest study was conducted by a Stanford University doctor, Christopher D Gardner, MD, a professor of medicine and the director of nutrition at the Stanford Prevention Research Center, part of Standford University, in partnership with luxury meal delivery service Methodology in a controlled nutrition trial at Stanford Medicine.
The study looked at the effects of different diets on the ability to control blood sugar, which is a good indicator of how easy or hard it is to lose weight and sustain it.
The health effects of these two popular diets, one focusing on low-carb ketogenic meals and the other on a high-fiber balanced approach built on plant-based ingredients central to the Mediterranean diet, showed that both strategies work equally well for weight loss.
The results showed the impact of switching to either a low-carb diet or a high-fiber mostly plant-based diet worked to help 40 participants with type 2 diabetes to control their blood glucose levels over 12 weeks. But a Mediterranean diet has been proven to be both heart healthier as well as more sustainable over time.
"Keto’s more severe carb restrictions did not provide additional overall health benefits," the study found, "making the Mediterranean diet just as effective and more easily sustained," according to Methodology CEO, Julie Nguyen.

Meal Delivery Made the Study Easier to Conduct

“Making changes to habitual dietary practices can prove to be daunting for many people, working with Methodology made it easy and we were able to get participants started from day one on getting the diet plans,” said Dr. Gardner of Stanford.
Investigators compared the two diet approaches and their effects on blood glucose, cardiometabolic risk factors, weight loss and nutrition, as well as how easily people can adhere to them.
  • The Ketogenic diet – ultra-low-carb, very high-fat diet that involves a drastic reduction in carbohydrate intake.
  • The Mediterranean diet – low-carb, moderately high-fat diet that emphasizes vegetables, legumes, fruits, whole grains, olive oil, and fish.
Half the participants started with Ketogenic meals and the other half with Mediterranean meals. After 12 weeks, the groups swapped diets for the remaining 12 weeks. This crossover design allowed the study to have built-in controls.
There were no additional overall health benefits to cutting out legumes, fruits, and whole grains to achieve an ultra-low-carb Ketogenic diet.
For people with diabetes or prediabetes, the less restrictive Mediterranean diet was just as effective in controlling glucose and easier to stay on over time.
“Restricting added sugars and refined grains and emphasizing the inclusion of vegetables should be the focus,” of a healthy diet, said Dr. Gardner. “There’s no reason to restrict heart-healthy, quality carbohydrate foods above and beyond.
Methodology's delivery service is currently available in the San Francisco Bay Area and Southern California with plans to expand later this year.

Bottom Line: Plant-Based Diet as Effective at Controlling Blood Sugar As Keto

For long-term weight loss choose a diet high in fiber-filled vegetables, legumes, fruit, whole grains, nuts, and seeds, to help control blood sugar and keep you feeling full longer.
For more healthy weight loss content, check out The Beet's Diet & Weightloss stories. To try a healthy plant-based diet, sign up for The Beet's 2-Week Plant-Based Diet Plan.

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