At a basic level, ketosis is just a switch in the fuel source your body uses. Without enough carbohydrates coming from your diet, and once you’ve burned through your body’s storage, your body starts making ketones from the fats you eat. Ketones become the new fuel source for the body. This is an evolutionary process that protected us from starvation when carbohydrates were not available.
Ketogenic diets take advantage of this biological hack to help us lose weight by burning fat for fuel. Without enough fat in your diet to meet all your caloric needs, your body starts burning through its own fat stores. That is why ketogenic diets are famous for fat / weight loss.
Before we get into the details, we must understand that we are talking about intentional dietary ketosis, not ketosis related to diabetes and ketoacidosis. Dietary ketosis is when someone decreases carbohydrate intake to the point the body can no longer use it as a primary fuel source.
Sometimes this occurs naturally during long fasts and even to some people just fasting while they sleep. Typically, those people have a high metabolism and few carbohydrate stores. That being said, if you are reading this, you are probably not one of them. Most of us have to try hard to enter into and maintain ketosis.
Although muscles, to a small extent, can use triglycerides and fatty acids for fuel, the brain cannot. However, it can use ketones. Ketones are made in the liver from triglycerides and fatty acids that come from either the diet or the breakdown of adipose tissue (body fat).
Once the liver processes the fats and converts them to ketones, they are released into the blood and act as the primary fuel source for the body. The body will remain in this state as long as carbohydrate intake remains low.
Dietary ketosis is usually defined by the amount of ketones in your blood, typically measured in millimoles per liter of blood, or mmol/L. 0.5 mmol/L is considered by many to be the lowest level of dietary ketosis.
These numbers are for blood ketone testing. Urine ketone testing results are usually listed as milligrams per deciliter. To convert, just move the decimal place one spot to the right. 0.5 mmol/L for blood results would equal roughly 5 mg/dL on urine test strips.
You will be in ketosis, but will fluctuate in and out of ketosis based on your carb intake and will probably not lose much, if any, weight. Optimal ketosis is usually defined as 1.5 mmol/L to 3.6 mmol/L. This is the best maintenance range for maximum fat burning and weight loss.
Anything over 3.6 mmol/L does not make ketosis more effective, so it shouldn’t be a goal. If your ketone levels go above 10, you should consult a healthcare provider to rule out ketoacidosis, which can be life threatening.
One thing to note is that, although you make get into ketosis around day 3-5, you will probably not be in optimal ketosis for a couple of weeks. This is because your body continues to adapt to the new energy source and becomes more efficient over time. See “How to Get into Ketosis” or “How Do You Stay in Ketosis” for more details. This is also why you should avoid cheat meals for at least the first 2-3 weeks, even if you use KetoSavior™ or KetoGuardian™.
*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.