Low carb, high fat diets have been used for centuries by doctors when working with obese patients. William Banting published the widely popular booklet titled ‘Letter on Corpulence Addressed to the Public’ in 1863. In this booklet he explained how he had slimmed down by eating a diet high in fat void of carbs. The Banting diet was used for decades by individuals looking to lose weight. Though the banting diet may not be a true ketosis diet, it did bring about many traits that are present on a ketogenic diet. One huge benefit being suppressed appetite. Combine this with lowered insulin levels from lack of carbohydrates and you have a 1-2 combo in decreasing body fat levels. Many people successfully use ketogenic diets today in their quest for decreased body fat levels for these exact reasons. By consuming a higher fat/lower carb diet you also retrain the body to use fat as an energy source. This allows the body to tap into its own fat reserves – burning it as energy.
http://www.youtube.com/watch?v=6NhtMk67fTs