 I'm embarrassed to say the thing that most shocked me in the research for the book was how unbelievably bad for your obesity is on average. It makes basically everything we fear significantly more likely. Dementia, heart disease, cancer. It's one of the biggest causes of cancer. Stroke, terrible crippling back pain, crippling knee pain, crippling hip pain. Just across the board, it's really bad for your physical and mental health.