"Calorie restriction or changes in dietary composition can enhance healthy aging, but the inability of most subjects to adhere to chronic and extreme diets, as

"Calorie restriction or changes in dietary composition can enhance healthy aging, but the inability of most subjects to adhere to chronic and extreme diets, as well as potentially adverse effects, limits their application." Well, obviously, when they call fasting / keto / etc. "chronic and extreme" within earshot of potential subjects, and use scary warnings, compliance will suffer. Other result of note: "No serious adverse effects were reported."