Is the keto diet appropriate for someone with a personal and family history of cardiac issues? My father recently passed away at age 59 from a sudden heart attack - no symptoms. He had a minor heart attack at 36, that time he had symptoms. He had type 2 diabetes and was on insulin for 7 years and had it well under control. His new PCP put him on the keto diet with the goal of getting him off insulin. He lost 37 lbs in 3 months and his A1C was under 6, but how might it have affected his heart?