One unique element of low-carb diets is the multi-week "induction" phase at the beginning of the diet. Normally much more strict than the diet itself, the induction phase is designed to bring your body into compliance with your forthcoming low-carb lifestyle. Although enduring the induction phase of a low-carb diet is often difficult, think of it as the gateway to a healthier you.
Typical Induction Phase
The typical induction phase for most low-carb diets lasts around two weeks. During this time, you will be normally asked to maintain a rigorously low-carb limit--usually between 20 and 30 grams per day. Additionally, you might be asked to abstain from fruits, and limit vegetable consumption to fibrous, green veggies like cucumbers, broccoli, spinach and lettuce.
Purpose of the Induction Phase
The reason for this strictness is that removing carbs for a prolonged period places the body into a state of ketosis. Ketosis refers to a physiological state where the body begins using fat as its primary fuel source. This state facilitates the effectiveness of many low-carb diets, as the body is constantly burning body fat, even in a resting state.
Benefits of the Induction Phase
In addition to promoting the changeover to fat as the primary fuel source, another benefit of the induction phase is mental fortification. After surviving for two weeks on an incredibly restrictive diet, the less-restrictive maintenance phases will not seem so burdensome. Knowing that cheating on your diet will result in the necessity of another induction phase, it also serves as a guard against prematurely ending the diet.
Symptoms of the Induction Phase
During the typical induction phase, you will experience several physical symptoms as the body makes the energy source transition from carbs to fat. Brain fog and lethargy are two common symptoms. Just know that these are a temporary byproduct of the diet, and will not last forever. Abandoning the diet at this point is common, but unnecessary. Just persevere and you will get through this phase within a few days.
Not all low-carb diets require a strict induction phase. Only those diets which seek to place your body in a state of ketosis will mandate a forced induction. Thus, if you have a job where you absolutely cannot be without your mental reserves for a day or two (such as an air-traffic controller), stick to higher low-carb, non-ketogenic diets to avoid this otherwise necessary evil.