Not related to cancer, but the general consensus in the medical community seems to be that keto is NOT a healthy diet. Though it can help with weight loss it contributes to poor heart health and just generally mucks up your cardiovascular system (that’s my medical term, not a doctor’s). I gained a few pounds during Covid and my GPs first, unprompted, advice was to avoid keto at all costs. Additional anecdote: my uncle recently lost a good amount of weight on a keto diet (5’8”, was 220 now about 168) and he promptly had a heart-attack. Doctors said he had “diabetic arteries” and that the keto diet was at least a contributing factor.