Ketone esters are supplements that claim to induce ketosis in the body without the user having to follow a ketogenic diet.
When the body is in ketosis, it burns fat for fuel, which is typically achieved by following the high-fat, low-carb keto diet or by fasting.
When glucose and glycogen (from carbs) are not available for energy, the body produces ketones.
Ketone esters were initially developed for use by the United States Army to enhance performance and concentration while also reducing inflammation.
Although research on ketone esters is limited, they may have undesirable side effects. A small 2012 study conducted at the University of Oxford discovered that participants experienced negative side effects such as nausea or dizziness after taking ketone esters.
While the FDA has classified ketone esters such as HVMN and Juvenescence as “generally recognized as safe,” doctors told Insider they are not convinced the beverages are necessary for good health or weight loss.
Ketone esters assert that they can induce ketosis without causing ‘keto flu.’
Many people who begin a ketogenic diet experience what is known as keto flu, which includes fatigue, irritability, nausea, constipation, and dizziness.
Ketone esters, like ketone salts (another type of exogenous ketone), are designed to induce ketosis without causing flu-like symptoms.
While it is possible to consume carbs and remain in ketosis while using ketone esters, some keto dieters use the supplement in addition to the diet to boost their ketone levels, according to biohacker Dave Asprey.
Ketone esters, which are frequently consumed as a daily beverage, are expensive: According to Keto Source, the first two brands to hit the market in 2018 are KetoneAid ($94.95 for three servings) and HVMN ($99 for three servings).
The drinks, according to those who have tried them, are also difficult to swallow, with GQ’s Brennan Kilbane describing the flavor as “a mixture of vodka, tequila, vegetable oil, and battery acid.”
Melia Robinson and Erin Brodwin of Business Insider tried HVMN and stated: “It caused tears to form in our eyes. We guffawed loudly.”
Ketone esters are unlikely to cause weight loss.
Ketone ester beverages are not low in calories; new brand Juvenescence’s keto ester beverage, Metabolic Switch, contains 210 calories. Including this beverage in your daily calorie total without reducing calories from other meals may sabotage your weight loss efforts.
However, small-scale research suggests they may suppress appetite — Kilbane reported in a GQ piece that he drank HVMN’s ketone ester in the morning and didn’t feel hungry until the end of the workday.
Dr. Spencer Nadolsky, a physician who specializes in weight management and obesity, told Insider that the beverages are “ineffective” for the majority of people.
“Ketone ester drinks may have some potential therapeutic benefits, but weight loss is not one of them,” he explained. “Even if blood ketone levels do increase, what purpose does that serve? The majority of people believe that ketosis or increased ketones result in increased fat loss.”
According to Nadolsky, ketone esters are a “massive marketing gimmick.”
“It’s just another source of calories with no evidence of weight loss,” he explained. “However, if it is used for any of the other therapeutic benefits being investigated, I would do so under the supervision of a well-trained physician.”
Ravina Bhanot, a doctor with the UK’s National Health Service, told Insider that ketosis can have health benefits as long as it is not used in place of a balanced diet.
“Continued use of the product on a daily basis for an extended period of time may result in adverse effects such as an increased risk of heart disease, kidney stones, decreased muscle mass, and confusion,” she explained.