This is a specific plan in a book written by Louise Gittleman, It has a forward by Barry Sears of "The Zone"

The Fat Flush Diet's program targets "cleansing" the liver~~.

Based on a combination of essential fats, proteins, and some carbohydrates, this plan is meant to boosts the liver's ability to function and claims to accelerate weight loss while improving your health.

I have only read a review of the book, not the book itself but the main aspects seem to be:
No white flour, white sugar, margarine, vegetable shortening, artificial sweeteners, or caffeine. The diet emphasizes essential oils (e.g., flaxseed and GLA), protein (eight ounces or more, plus two eggs a day), vegetables, thermogenic spices (e.g., ginger and cayenne), water, and diuretic beverages (eight glasses/day of diluted, unsweetened cranberry juice). In its first two-week phase, the plan is a rigid, low calorie (1,100-1,200 calories/day), low-carb (no grains or starchy vegetables) diet. Phase two lets you increase your calories to 1,500 and add two "friendly carbs." Phase three, the "lifestyle program," moderately adds more dairy, carbs, and calories. Gittleman promotes walking and recommends strength training in phase three.

I first saw it on ivillage. Not my sort of thing.