The theory behind a ketosis diet is that your body will burn fat rather than carbohydrates if you deprive it of almost all carbohydrate sources. This means limiting your carb intake to just 20 grams in some cases.
Normally, the carbohydrates in food are converted into glucose. The glucose is then transported through the body and is particularly important in fuelling the brain. However, if there are very little carbs in the diet, the liver converts fat into fatty acids and ketone bodies. The ketone bodies pass into the brain and replace glucose as an energy source. Thus, the body produces ketone bodies—a state known as ketosis.
Low Carb diets take advantage of this state of ketosis. Since cells in the body can use ketones for energy instead of glucose, and since ketones are easier to produce, only a small amount of glucose is created. In other words, ketosis is the more significant process in this case. Diets low in starches and sugars do not directly affect blood sugar levels significantly, meals tend to have little direct effect on insulin levels. These diets tend to discourage insulin production in general.
Additionally, many experts argue that a ketosis diet is more like the diet our bodies have evolved to use. Prior to the advent of agriculture just a few thousand years ago, the human body had millions of years of evolution which selected for a hunter gather lifestyle. Hunter gatherers had very few carbs in their diets. They may have had the original ketosis diet.
Dr. Robert Adkins first published the Adkins Diet Revolution in 1972 which set off the modern round of low carb dieting. At the time, its appeal was limited because so many scientists and doctors condemned it. Over time, though, it gained credibility and when he republished the book as Dr. Adkins New Diet Revolution, it set off a frenzy.
While the scientific community still hasn’t acknowledged the value of the ketosis diet, they have started to make recommendations that people reduce the amount of carbohydrates in their diets. The medical community has stressed the importance of fiber in diets and recommended that children not drink juice on a regular basis.
There has been much scientific research on low carb diets. There are many studies which show it works and many studies which show that it is dangerous. Because of these competing studies, advocates on both sides can pull up evidence that they are right.
Once you do your due diligence, you will be better able to decide whether to pursue a ketosis diet.