Keto diet may reduce mortality without increasing cardiovascular risk

Key takeaways:

• The ketogenic diet was tied to a reduced risk for all-cause death while sustaining heart health.
• Anti-inflammatory properties and enhancement of metabolic health may have contributed to the results.

The ketogenic diet could reduce the risk for all-cause mortality by up to 24%, an analysis published in Scientific Reports showed.

Results from the cohort study suggest the keto diet did not increase the risk for cardiovascular disease-related death despite its content possibly contributing to a higher risk for cardiovascular diseases.

Research has previously suggested that the ketogenic diet may offer benefits for several health outcomes and conditions, such as metabolic health and psychiatric symptoms.

Xiaolong Qu, from the Shanghai Jiaotong University School of Medicine in China, and colleagues explained that cardiovascular disease plays a significant role in global mortality, but the relationship between the effects of chronic disease and the ketogenic diet — which emphasizes low-carbohydrate and high-fat intake — remains conflicting.

“On one hand, reducing carbohydrate intake and enhancing insulin sensitivity may confer beneficial effects on CVD risk factors such as BP and lipid levels,” they wrote. “Conversely, the high-fat content of the [ketogenic diet], particularly saturated fat, may exert detrimental effects on lipid metabolism, trigger inflammatory responses and augment CVD risk.”

In the study, the researchers examined data from the National Health and Nutrition Examination Survey from 2001 to 2018 to determine the impact that greater adherence to the ketogenic diet has on all-cause and cardiovascular disease-related mortality.

The final analysis included 43,776 adults (mean age, 49 years; 48.3% women), of whom 13.8% died from any cause and 3.5% died from cardiovascular disease, respectively, during a mean follow-up period of 9.1 years.

Initially, Qu and colleagues found no association between the diet and risk for all-cause death in unadjusted models.

However, a greater adherence to the diet significantly reduced the risk for all-cause mortality (HR=0.76, 95% CI,0.63-0.9) after they adjusted for several factors.

Furthermore, the ketogenic diet did not correspond with higher cardiovascular disease-related mortality risk.

In subgroup analyses, the effect of the ketogenic diet on the risk for all-cause mortality was particularly significant in women, those aged 60 years or older, those with a BMI of 24 kg/m² or greater and nonsmokers.

The researchers highlighted several mechanisms of the ketogenic diet that may have contributed to the results, which include:

• the improvement of metabolic health, which reduces chronic conditions — like diabetes and cancer — that collectively contribute to all-cause mortality;
• modulation of the gut microbiota, which prevents gastrointestinal diseases and improves immune function; and
• anti-inflammatory and antioxidant properties that protect against cognitive decline and other chronic diseases.

Qu and colleagues acknowledged some limitations in the study. These included self-reported assessments of dietary habits and a lack of measurement of ketosis levels, the latter of which “poses a significant constraint in examining the relationship between ketosis and mortality risk,” they noted.

Still, they concluded that the ketogenic diet may provide benefits from a public health perspective “by offering innovative therapeutic approaches for patients with obesity, metabolic syndrome, and certain refractory diseases,” they wrote.

“By implementing scientifically and logically tailored dietary adjustments, the ketogenic diet can contribute to improving the health status of these patients, mitigating the societal medical burden, and enhancing overall well-being,” they continued, adding that the ketogenic diet’s high-fat intake could disrupt nutrient balance and strain liver function in some populations, and that “personalized guidance and vigilant monitoring should be emphasized” when promoting the diet.