Exogenous Ketone Supplements: Potential Benefits, Known Risks, and More

Potential Benefits of Exogenous Ketones

The research on exogenous ketone supplements is mixed and limited. While some small, early studies point toward possible health perks, experts still don’t have enough evidence to fully endorse these.

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Potential Benefits of Exogenous Ketones May Boost Cognition May Support Exercise Endurance May Lower Blood Sugar

“While the research on exogenous ketones is intriguing, I believe it’s still far from conclusive,” says Hector Perez, MD, a bariatric surgeon at Renew Bariatrics in Tijuana, Mexico. “There are a handful of small trials, some with only 15 to 20 healthy participants, which are not enough to justify sweeping recommendations.”

Keeping that in mind, here’s what some of that research has found thus far.

May Boost Cognition

“Some early data suggests potential cognitive or neurological benefits, possibly because ketones offer a cleaner fuel source for the brain,” says Dr. Ednie.

Although the brain usually uses glucose for energy, it switches to ketones when glucose levels are low. Since ketones don’t need insulin or certain transporters to reach brain cells, they can be helpful when not enough glucose is available. Research shows that insulin resistance harms brain activity, reducing communication between brain cells, but many of these brain functions improve when ketones are added (particularly memory-related activity). The study was conducted on mice, however, so human studies are needed.

“Early human studies are encouraging and show real promise, but the sample sizes are small and longer-term effects are still being studied,” says Dr. Perez. “It could be helpful for those with cognitive sluggishness, but it’s not a wonder focus pill for the healthy.”

It’s worth noting that research on humans indicates that a keto diet that doesn’t include ketone supplements may also benefit cognitive function such as memory and attention.

May Support Exercise Endurance

Exogenous ketone supplements may theoretically boost endurance in athletes by increasing erythropoietin, a hormone that supports the body in delivering oxygen to muscles. But some research shows mixed results that may be partly due to inconsistencies between individual subjects and a lack of long-term data.

“Ketones improve cardiac efficiency and may support muscle recovery, especially under metabolic stress, but performance boosts seem inconsistent,” says Perez. “There is strong mechanistic data from both animal and cellular models, but clinical trial results in athletes seem context-dependent.”

In other words, athletic performance may not improve for everyone who takes this supplement. “Some athletes report enhanced endurance; others see no difference — or even negative effects,” Ednie adds.

A systematic review that evaluated 16 performance outcomes of ketone supplementation from 10 studies reported three studies showed positive effects, three studies showed negative effects, and the remaining studies didn’t show any meaningful change in either direction. The discrepancies in the data may be partly due to differences in the type of supplement, dose, and performance tests between the studies, but the authors concluded that there isn’t enough evidence to recommend ketone supplements to increase performance.

May Lower Blood Sugar

One review conducted in Canada showed that ketone supplements, particularly ketone esters, lowered blood sugar in healthy people, those with obesity, and those with prediabetes or type 2 diabetes. This may be due to a combination of factors, including their ability to decrease how much glucose the liver makes and their stimulation of insulin release.

“Exogenous ketone esters acutely lower blood glucose, even without insulin, which can be useful in insulin-resistant or post-op patients needing rapid stabilization,” says Perez. “The evidence for short-term glucose reduction is strong and well-documented in controlled human trials, but there’s still limited research on long-term results.”