Keto Lean Ultra:- For some people, it’s about weight decrease. “Overall, [the keto diet] ends up being low-calorie,” Langer says. “You’re eating 80 percent of your calories in fat, yet it’s very filling.”Dina Griffin, RDN, with eNRG Performance in Littleton, Colorado, says people are also pulled in to the eating routine for the potential anticancer and quieting benefits and the helpful result it’s been seemed to have on athletic performance.