A clinical trial published August 27 in the Cell Press journal Cell Metabolism revealed that a very low-carbohydrate, high-fat ketogenic diet may provide stronger metabolic benefits for people with obesity than either a Mediterranean diet or a low-fat diet. After four to five months on a ketogenic (or “Keto”) diet, about half of the participants with obesity and prediabetes no longer met the criteria for prediabetes.
“We know weight loss can improve metabolic health in people who are obese,” says Samuel Klein, the study’s corresponding author at Washington University School of Medicine in St. Louis, Missouri. “Our data suggest that if you have high liver fat content and prediabetes, reducing carbohydrate intake can have important therapeutic effects on metabolism beyond just weight loss alone.”
Comparing Three Popular Weight Loss Diets
An estimated 40% of adults in the United States have obesity. Doctors often recommend low-fat, low-carbohydrate, or Mediterranean diets for weight loss, but researchers have not known whether one approach provides extra metabolic advantages beyond the effects of losing weight.
Not all diets are created equal when it comes to reversing the metabolic damage of obesity, even when they produce the same amount of weight loss, according to a new randomized clinical trial published in the journal Cell Metabolism. Diet macronutrient content affects the cardiometabolic benefits of weight loss.
“Obesity causes a constellation of metabolic diseases, including atherogenic dyslipidemia, prediabetes, and metabolic dysfunction-associated steatotic liver disease, which are risk factors for type 2 diabetes and cardiovascular disease,” said Dr. Samuel Klein from the Washington University School of Medicine in St. Louis and his colleagues. “Insulin-resistant glucose metabolism in both skeletal muscle and liver is the key pathogenic driver of obesity-related metabolic diseases.”
“Weight loss induced by decreasing energy intake relative to energy expenditure is the cornerstone of therapy for people with metabolically unhealthy obesity because it improves multi-organ insulin action and ameliorates, or even completely resolves, obesity-related metabolic diseases.”
Clinical Trial Findings
WashU Medicine researchers led a clinical trial testing three diets with different proportions of carbohydrates, fats and proteins and found all of them improved metabolic health, but a very low-carb ketogenic diet had additional benefits for liver health and blood sugar control.
There is no shortage of popular diets to try, and they can generally produce weight loss if followed to the letter. But are all diet plans created equal in terms of reducing the cardiometabolic risks that come with obesity, such as Type 2 diabetes and liver disease? A randomized clinical trial from Washington University School of Medicine in St. Louis suggests they aren’t, even when they lead to identical amounts of weight loss.
Comparing three commonly recommended diet plans, the researchers found that losing weight on any of them improved overall metabolic health in adults with obesity who also had elevated blood sugar and excess fat in their liver — which are important risk factors for developing diabetes.
A new study comparing ketogenic, Mediterranean, and low-fat, plant-forward dietary plans found that they all help with weight loss, with improvements in body fat and insulin sensitivity. However, the keto diet produced the largest reduction in liver fat and was also associated with greater improvements in prediabetes.
Although the study was small and short-term, the findings suggest that diet composition may matter beyond weight loss, and the keto diet showed the greatest changes in hormone and insulin levels linked to liver fat metabolism.
Dietary Changes and Metabolic Health
Dietary changes are often an initial approach to support healthy weight loss, as modifying food choices and overall calorie intake can help create a sustainable energy deficit. In particular, eating plans that emphasize nutrient-dense foods and appropriate portion sizes can support gradual and sustainable weight reduction.
Approaches such as the ketogenic (keto) diet may promote weight loss by substantially reducing carbohydrate intake and increasing fat intake, which can lead to reduced appetite and lower overall calorie consumption for some individuals.
A keto diet could provide additional health benefits for people with obesity and prediabetes compared to other popular weight-loss plans, according to new research. A clinical trial found the very low-carb diet produced greater improvements in several measures of liver and metabolic health than Mediterranean and low-fat diets when participants lost similar amounts of weight.
The findings, published in the journal Cell Metabolism, showed that after following a ketogenic, or “keto,” diet for four to five months, around half of participants with obesity and prediabetes no longer met the criteria for prediabetes. The diet also produced the largest reduction in liver fat among the three diets tested.
Study senior author Samuel Klein, from Washington University School of Medicine in St. Louis, Missouri, said: “We know weight loss can improve metabolic health in people who are obese. Our data suggest that if you have high liver fat content and prediabetes, reducing carbohydrate intake can have important therapeutic effects on metabolism beyond just weight loss alone.”
Health care providers often recommend low-fat, low-carbohydrate, or Mediterranean diets for weight loss, but previous research has not conclusively demonstrated whether one approach provides extra metabolic advantages.
The keto diet provides greater health benefits than other popular weight-loss plans, according to new research. Clinical trials showed that the very low-carb diet also boosts the liver as well as helping to shed weight.
The keto diet that severely limits carbohydrates but is high in fat has the greatest health benefits for obese people compared to a Mediterranean diet or a low-fat diet, say American scientists.
