Ketogenic diets, raspberry ketones, and all things fat-burning are all the rage. What is the truth about your metabolism and ketones?
When I was in Naturopathic Medical School, the Atkins diet was making a come-back. Originally developed in the 1960’s by the cardiologist Dr. Atkins, the paperback book about it came out in 1981. By the late 1990’s the New Diet Revolution came out, and that is what I discovered.
With my basic medical school background in biochemistry, it seemed genius to get into the starvation mode of fat-burning ketosis while preserving muscles by eating plenty of protein. Unfortunately, my biochemistry studies did not include the nuances of what else happens in a ketotic, or fat-burning metabolic state, and honestly, a lot of it may not have been known in 1995.
I played with the Atkins diet at that time, seeing how to do it by staying in ketosis, while eating as “healthy” as I could manage. Plenty of vegetables have little carbs, so I was able to eat them and still stay in ketosis. At first, I lost weight, but later, while still on the diet, I stopped losing weight.
Maybe I wasn’t doing it right, I thought. Well, the keto sticks showed I still was in ketosis, so what gives? I eventually gave up on it, and now I understand what was happening.
There is a big difference between the body making ketones and losing weight.
Let’s explore the myths and truths of ketones and ketosis.
Definitions
Fuel: Our bodies can only burn a few different molecule types for energy. These fuel molecules are known as carbohydrates, fats, alcohol, and ketones. If the body cannot burn any of these for energy, it stores it in some form for later.
Ketones are an alternative source of fuel for the body. It switches to making ketones when there is not enough food intake. Ketones are also constituents of food and are created synthetically as supplements.
Metabolic ketosis is the state in which the body has run out of carbohydrates to burn for fuel and turns to fats to burn for fuel. The body then converts stored fat to ketones to burn for fuel. It is a survival mechanism for the brain because when we have no glucose to burn, we can burn ketones for energy so we can still look for food.
A ketogenic diet is where there are not enough carbs from the diet to burn for fuel, so the body switches to making ketones for fuel. With some carbohydrates and some protein, an intermediate called “oxo acetoacetate” is made which is necessary to burn fats as fuel. Without that, the body makes ketones from fat for fuel.
Diabetic ketoacidosis is the state of untreated diabetes mellitus with rapid weight loss and wasting. Blood sugar is high because insulin, the hormone that escorts sugar into the cell to be burned as fuel, is nearly absent. Therefore, the body creates ketones from body fat to burn for fuel.
The effects of ketosis
Benefits
- Ketones help suppress appetite
- Ketones help with mental alertness and focus
- Ketones have been shown to help Epilepsy that does not respond to medication
- Ketones have been shown to help Alzheimer’s disease
- Ketones have been shown to be the preferred fuel source for a postmenopausal woman’s brain
Possible detrimental effects
- Since your body gets into the fat-burning state since there is no carb fuel, this state can raise stress hormone levels such as cortisol
- For the same reason, sleep can be affected
- A prolonged ketosis state may cause loss of muscle mass
- It can change your gut flora and encourage yeast overgrowth
The truth of how your body burns fuel
When you eat a well-rounded diet, your body is getting protein, carbohydrates, fats, and little bits of alcohol for fuel. Then you can flip the metabolic switch.
Overnight since the last meal, the body usually begins to make ketones as a source of fuel when it has run out and can’t make glucose fast enough from its stored form, glycogen.
The body may also make ketones for fuel under prolonged exercise, more than about 70 minutes. Any time there is not enough fuel of any kind the body will make ketones for fuel.
That means that if you only ate one candy bar a day, your body would be making ketones for fuel. You would be losing weight because your requirements for fuel are not being met by your dietary intake. However, I do not recommend this kind of plan for weight loss.
The myth of the ketogenic diet
Where I went wrong with the Atkins diet, and what I see said about the ketogenic diet for weight loss, is that it does not matter how much food you are consuming, so long as you are still peeing on the keto sticks proving you are producing ketones, you will lose weight.
There is a myth that if you follow a ketogenic diet, putting your body into a state of ketosis, you can shed pounds like it is nothing, due to this metabolic miracle. The body is much more nuanced.
The reality is a ketogenic diet is not sustainable as there are benefits to eating carbohydrates as well – gut microbiome, production of hormones, and a variety of plant foods. And ending weight loss plateaus.
The key is to be able to switch from burning carbs to burning fats, and there are many programs for a fasting lifestyle that do that.
Your experience
Are you on a ketogenic diet, or have you been on one? What has been your experience? Please comment below.
