I was thinking of those brokenhearted parents when I saw a clip of Robert F. Kennedy Jr., the secretary of health and human services, claiming that a doctor “up at Harvard has cured schizophrenia using keto diets.” (A ketogenic diet, which has been used to help children with epilepsy, is one that is heavy in fats and low in carbs and protein.) He added that he’s seen studies about how people lose their bipolar diagnosis by changing what they eat.