Exogenous ketone esters have been found to be safe in humans and animals. Additionally, ketone salts have been granted GRAS (generally recognized as safe) status. Several studies have used both ketone salts and ketone esters in both animals and humans with no adverse side effects. A recent study in 2020 showed no adverse effects on consuming over 25 grams of ketone salts daily for 90 days in healthy adults.