Sherlock Holmes Diet: Of the sparest. Shun all food in favor of the strongest tobacco at least fifty percent of the time. When you do finally eat, choose animal proteins – a side of cold beef, bacon, oysters, a brace of partridges – with cups of tea and the occasional bit of bread. Moderate alcohol is permitted as are green peas, when babbled of by your landlady.
Dr. Watson Diet: You are permitted proteins, carbohydrates, teas, and vegetables with moderate alcohol and tobacco because this diet focuses on physical exercise. Meals are only to be eaten on the run, and on a regular basis you will not permitted to finish your meal. Your constant activities – being dragged out of bed at all hours, chasing after consulting detectives and dangerous criminals – guarantee you will burn off any calorie you consume.
Irregulars Diet: Gutter scraps, hand-outs, unwanted garbage. Even if you're lucky enough to find these, you will be highly reluctant to actually eat them. Exercise includes trailing suspects and dodging bobbies. The occasional sneaky foray into Mrs. Hudson's cookie jar is a permissible supplement, provided you actually get past Mrs. Hudson.
Mycroft Holmes Diet: Eat anything and everything, walk as little as possible, perform as many activities as is humanly possible from your armchair. In other words, do worse than you were doing before!