There are a lot of different diet programs out there; my body is a jiggling testament to the effectiveness of many of them.
There are some diets that claim our bodies were never meant to eat refined food. Others claim the human gut maintains a tight schedule so only certain foods may pass through it at certain times. To ignore that schedule means weight gain because, of course, the prohibited food gets chucked onto the fat pile.
One of my favorite misguided notions is there’s pounds of undigested red meat stuffed somewhere up our fussy colons. Speaking as someone who’s actually had a movie camera threaded through that long and winding path, trust me, there is no red meat (undigested or otherwise) at the end of the rainbow. During the long preparation for my close-up, Mr. Demille, I’d swear I passed a lego block I’d ingested as 
a child but there was no sign of even last week’s roast beef.
Some diets claim certain foods can not be eaten together. I’m not talking about keeping Kosher or Halal. The laws of Kashruth are more like the Manufacturer’s recommendations for a car: interesting, helpful but not essential for proper maintenance.
The ‘mutually exclusive’ category of diets claim it is the nature of certain foods to compete or bind with other foods or somehow turn to fat in their prescence during digestion. The irony here is the people who follow these diets will chow down on some foods that contain chemicals that actually do precipitate out desirable nutrients like 
calcium. It’s not digestion, however, it’s chemistry.
There is another, quasi-Ayurvedic approach that indicates we should eat according to our blood types. I put that in the ‘what’s your sign’ category of diets.
Over the years I’ve learned if a diet claims ‘doctors don’t want you to know’ about it, there’s a good reason. MD’s went to school for a long time to learn about what is and what isn’t shinola. They don’t want to spend valuable time explaining that difference to you.
So, I drive across town to weigh in and sit for half an hour listening to other fat people talk about spagetti squash and kale chips. This diet has been around for years, it makes nutritional sense, does not rely on magical thinking and it works. In fact it works so well there are at least a hundred successful commercial imitators who’ve made nice profits with nowhere near the same success rate.
Besides, I’m a huge fan of behaviour modification and this one hits all the notes like a BF Skinner song book.
Hello, my name is Maureen and I’m fat.
