Staying on the keto diet long term could carry health risks

The Keto Diet: Exploring Benefits, Risks, and Long-Term Health Implications

Chances are you’ve come across mouth-watering videos of influencers creating keto-friendly meals, from crispy almond flour French fries to sandwiches made of fried cheese instead of bread. These tantalizing recipes are all part of the ketogenic (keto) diet, which primarily aims at weight loss.

At the heart of the ketogenic lifestyle is a fundamental shift in macronutrient intake, where fats take center stage, and carbohydrates are minimized to a bare minimum. This marks a stark contrast to the low-fat diet trends that were popular in the 1990s. The concept behind keto is that when you cut out carbs—our usual energy source—the body adapts by using fat for fuel instead. The liver converts this fat into ketone bodies, providing an alternative energy source and promoting weight loss in many individuals. This dietary shift has gained immense popularity in America, prompting many to consider it a potential path toward improved health and weight management, according to Molly Gallop, a physiologist at Earlham College in Richmond, Indiana.

While the keto diet might show short-term success in weight loss, recent research indicates potential long-term health risks. A study published in Science Advances on September 19 finds that mice subjected to a ketogenic diet for nearly a year—equivalent to decades of human time—faced significant health challenges, including glucose intolerance and indications of liver and cardiovascular disease. Gallop and her team emphasize that the keto diet’s appeal may overlook these potential hidden costs.

Physiologist Amandine Chaix, from the University of Utah, echoed this cautionary perspective, indicating that the keto diet is not an “magical dietary approach” and urges those on the plan to be cautious of its long-term implications.

The ketogenic diet did not begin as a trend; it was originally a medical dietary intervention. About a century ago, doctors began employing it as a treatment for epilepsy, as short periods of this diet helped alleviate seizure symptoms. Johns Hopkins neurologist Tanya McDonald still uses keto as a treatment option for epilepsy today, noting that the classic keto composition specifies that approximately 90% of total caloric intake should come from fat—almost double the fat proportion typical of an American diet.

Numerous studies document weight loss success among overweight individuals on keto, yet long-term effects on the general population remain poorly understood due to the restrictive nature of the diet. This aspect is easier to assess in animal studies, as Chaix’s research demonstrates. Mice on a keto diet for eight months exhibited various health metrics, with weight measurements indicating that those on low-fat diets were the leanest. Even so, mice on keto still weighed less than those on a conventional Western diet, suggesting that high-fat, low-carb options can be effective for weight maintenance.

However, the research unveiled concerning results as well: mice consuming a keto diet exhibited elevated fats in their bloodstream—a primary signal of cardiovascular problems. Additionally, fat accumulation in male mouse livers indicated impaired organ function. Furthermore, these mice encountered difficulties regulating blood sugar levels; their insulin-producing cells struggled to release necessary hormones, causing abnormal blood sugar metabolism. The specific reasons behind this dysfunction remain a mystery, prompting further investigation into the keto diet’s cellular impacts.

This research aligns with McDonald’s cautions, as she advises against the unsupervised adoption of ketogenic diets by the general population. If individuals do choose to indulge in high-fat meals, it’s important they keep their healthcare providers informed, allowing for monitoring of potential health issues.

Despite these concerns, Chaix’s study offers a hint of optimism: when the mice discontinued the keto diet, their blood sugar regulation issues were resolved. This indicates that some adverse effects may be temporary, a reassuring notion for those worried about the diet’s consequences.