What Is Ketosis?

The word “keto” has exploded all over the media and the marketing world. What does this mean? The word “keto” is short for ketosis and ketogenic diet. There are thousands of books and cookbooks on “the ketogenic diet” and a full spectrum of “keto” products to buy and eat, drink, and supplement your diet, with promises of weight loss, increased athletic performance, and a “cure” for diabetes. As whole-food proponents, we do not recommend any commercial processed “keto” products.


The first misconception that I want to clear up is the difference between ketosis and ketoacidosis. These are two different words! They just happen to begin with the same four letters and end with the same three letters. Early in my reversing diabetes journey, I learned about ketosis and I was excited to share my newfound knowledge with my then-very-small Adventist Vegetarian Diabetics Facebook group. “Oh, no,” exclaimed one member, “you could die from ketoacidosis!” So I had to explain to her that nutritional ketosis is not the same as diabetic ketoacidosis (DKA).

DKA happens primarily in Type 1 diabetics when they don’t have adequate insulin and their body starts producing ketones but they keep eating high amounts of carbohydrates, resulting in high blood sugar. It is the combination of high ketones and high blood sugar that is so deadly.

Nutritional ketosis is a normal metabolic state when the body does not have sufficient carbohydrates (sugars and starches) to burn for fuel (energy) and so starts burning ketones made from body fat.

Dr. Anthony Gustin summarizes it in his chart, “Ketosis vs. Ketoacidosis,” below this article.


The second misconception I want to dispel is that there is NO a, or the, or one ketogenic diet. Any dietary protocol that allows one to achieve and maintain ketosis (as described below) is the ketogenic diet for that person. There are no set dietary rules for a ketogenic diet. It is simply “the nutrition used to achieve and support the state of ketosis,” according to CaliDiet magazine. Some people have reported being “in ketosis” while eating as much as 50 grams of carbohydrates per day, while others need to go as low as 20 or even 10 grams of carbohydrates per day. But it is generally agreed that carbohydrates from sugars and grains will keep you “out of ketosis.”


WebMD, in all its cautious simplicity, says:

“Ketosis is a normal metabolic process, something your body does to keep working. When it doesn’t have enough carbohydrates from food for your cells to burn for energy, it burns fat instead. As part of this process, it makes ketones. Ketones are substances that are made when the body breaks down fat for energy. When you cut way back on your calories or carbs, your body will switch to ketosis for energy.”

But the clearest explanation of ketosis is from the classic volume, Keto Clarity, by Jimmy Moore with Eric C. Westman, MD, from which I quote:

“Ketosis (pronounced KEY-TOE-SIS) is a metabolic state that happens when you consume a very low-carb, moderate-protein, high-fat diet that causes your body to switch from using glucose as its primary source of fuel to running on ketones. Ketones themselves are produced when the body burns fat, and they’re primarily used as an alternative fuel source when glucose isn’t available. In other words, your body changes from a sugar-burner to a fat-burner…. So ‘being in ketosis’ just means that you are burning fat.

“If you consume a diet with very few carbohydrates, moderate levels of protein, and plenty of healthy saturated and monounsaturated fats, then these ketones will begin to increase until they dominate the way your body is fueled, to the point that very little glucose is needed to function.”


Living Life Keto says that keto-adapted, or fat-adapted, is the state in which the body no longer prefers to use glucose or carbs for fuel but rather fat. How is that accomplished?

Ask Dr. Matthews summarizes the process as:

Step 1 – Drastically reduce carbohydrate intake, and glucose levels fall. The most common advice is to restrict carb intake to 20 grams (net) carbs per day.
Step 2 – Lipase releases and stores triglycerides
Step 3 – Fatty acids travel to the liver
Step 4 – Liver produces ketones
Step 5 – BHB is synthesized in the liver and can be used as an energy source for every cell in the body, including brain cells.

Keto Clarity lists three types of ketone bodies:

  1. Acetoacetate (AcAc), the primary ketone body in the urine. Urine test sticks are only useful in the early stages of ketosis. Once you are fat-adapted, the urine ketones disappear.
  2. Beta-hydroxybutyrate (BHB), the primary ketone body in the blood. This testing is the most precise.
  3. Acetone, the primary ketone body in the breath. This testing is least invasive and correlates well to BHB testing.

Being in nutritional ketosis as brought on by a low-carb high-fat (LCHF) diet will absolutely not cause DKA (diabetic ketoacidosis).


Living Life Keto says, “There is no real way to test if you are keto-adapted but there are plenty of ways to tell by simply observing changes in your life and how you feel.” Some of the immediate effects of ketosis are:

  • You do not get hungry as often! The natural partner of ketosis is intermittent fasting. (And that’s another whole topic!)
  • You feel more mentally alert and can think more clearly. “Brain fog” diminishes significantly.
  • Your energy levels even out and usually increase from their pre-keto levels. Instead of the roller coaster rise and fall of energy that accompanies a carb-filled diet, fat burners enjoy a steady stream of fuel regardless of when they’ve eaten last.
  • You may feel calmer without hunger and carb cravings or low energy.
  • You may be able to exercise/workout more easily. In general, you can just feel your body running more efficiently.

More significant benefits include:

  • Weight loss is easy, accompanied by reduction in body measurements and clothing sizes.
  • Lowering of blood glucose and insulin levels. Diabetics experience lower A1C and fasting blood glucose numbers.
  • Other health issues respond to ketosis, such as lower blood pressure, lower triglycerides, higher HDL, improved thyroid health, and many others.


For an easy-to-read, comprehensive “course” on how to implement a ketogenic diet, refer to the Diet Doctor’s “A ketogenic diet for beginners” at https://www.dietdoctor.com/low-carb/keto.

Some of the things that will sabotage a ketogenic diet are:

  1. Not restricting carbs enough
  2. Not eating enough healthy fats
  3. Eating too much protein
  4. Eating too much of anything,* or eating too often
  5. Not getting enough electrolytes (sodium, magnesium, potassium)

The classic resource on ketosis is Keto Clarity, by Jimmy Moore with Eric C. Westman, MD. <https://smile.amazon.com/Keto-Clarity-Definitive-Benefits-Low-Carb/dp/1628600071/ref=sr_1_3>

* “Eat until you are 80 percent full” is the way most children in Japan are raised. Is it a coincidence that Okinawa is well-known for having the highest proportion of people living beyond the age of one hundred? —Dr. Eric Westman

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