Is this just an excuse to eat bacon all day? Not exactly, but the diet works by requiring people to drastically reduce their consumption of carbohydrates and replace them with protein, whether it's bacon, cheese or eggs. The idea is that overweight people tend to eat too many refined carbohydrates, or empty calories. Without carbohydrates, the body will then begin burning the fat that they initially produced.
However, nutritionists and doctors are concerned about a couple of aspects of this diet. The first is a process known as ketosis -- where the body burns its own fat stores as energy [source: Nordqvist]. The harmful side effects can be halitosis, constipation and even kidney and liver damage (unless the person consumes lots of fluids), since these organs have to work overtime to process the elevated levels of protein. Finally, carbohydrates have always been part a building block of a healthy diet that leads to sustained energy and healthy brain function [source: Hardy]. Without carbohydrates, you may be skinnier, but not necessarily healthy. And then what's the point?