The Keto Watchers' diet plan is based on what is called "optimal ketosis". To understand what optimal ketosis is we must first look at what regular ketosis is.
Ketosis* is a conversion that happens in the body. It is a natural and harmless condition for healthy people. Everyone produces ketones constantly, but mostly at night and when we go for longer periods without food (such as during intermittent fasting). Most people who exercise a lot will also be in a state of light ketosis after a long exercise session.
The human body primarily has two different forms of fuel for energy - carbohydrates or fat. The body prefers to burn the carbohydrates first. That means as long as it gets constantly replenished by too many carbohydrates through the diet it will never be able to burn of the other source; fat. When you cut carbohydrates from the diet (by a ketogenic diet or low carb diet) and the body has used up the few carbs it has stored from carbohydrates in its glycogen-storage, your body has no choice but to burn fat instead. Ketones are residue from this fat-burning. The ketones, floating around in your body, then take over most of the tasks that the glycogen had been doing; to supply the brain and muscles with energy. And these ketones are just as effective if not more. It has been claimed from several sources that both the heart muscle and the brain work better on ketones than on glucose. There are several hormones involved in this game. It is when this happens in the body that people say they are "in ketosis".
The body needs some glucose for certain types of tissues, but even if you don't eat any amount of carbohydrates it can still produce what little it needs from fat molecules and proteins. As the adjustment to a low carb diet has lasted for at least a couple of weeks, most people will begin to notice an amazing improvement cognitively. The brain has continuous access to ketones and is not exposed to blood glucose fluctuations common every 3 hours. Hunger, sweet-tooth, and cravings will disappear completely from your life! You may suddenly find that you forgot to eat! It is easy to go for a long time without food since your body retrieves what it needs from your fat reserves.
Many will see the pounds and kilos will fall off! However, some might only experience weight-loss for a short amount of time. This is because there is a difference from person to person in how much ketones your body will produce. So regular ketosis does not necessarily mean weight loss for all! Some have to reach a certain amount of ketones in their body to get to their goals. That is where "optimal ketosis" comes in.
*Ketosis must not be confused with ketoacidosis, which is a diabetic state of acid poisoning in the body.