Ketones are the new darling in the health/wellness/nutrition/diet universe. If you are as old as I am you may remember them from several decades ago as being one of the cornerstones of the Atkins Diet, popularized by Dr. Robert C. Atkins. If so, and that is where your knowledge ends, then you may be wondering why are they back in the spotlight because don’t we now know that ketones are bad? Or maybe if you are younger (and not a biochemistry geek) you are scratching your head saying “What in the heck is a ketone?”
Ketones are produced by our bodies as a byproduct of burning fat for fuel. When our bodies are burning fat as their primary fuel source then we are in “ketosis”.
Now what we usually think of as a primary fuel source for our bodies is glucose. And especially with our modern carbohydrate rich diets, for most people it is the primary fuel source. Glucose is produced when carbohydrates are burned for fuel. But our bodies are adapted to use ketones during times of fasting and starvation when food is not readily available to produce glucose.
But we don’t have to fast and starve ourselves to produce ketones and burn fat for fuel. Our bodies will naturally produce and use ketones when we eat a low carbohydrate, moderate protein and high fat diet. This is called a “ketogenic diet”.
Unfortunately, ketones often have a bad reputation, even with medical professionals. Perhaps because they can be associated with starvation. But also because of some confusion between “ketosis”, the state of the body burning fat for fuel, with a serious condition called “ketoacidosis”.
When diabetics do not get enough insulin they produce ketones. Insulin is the key for glucose to enter the cells from the blood. When there isn’t enough insulin, the body can’t use the glucose in the blood that is produced from what you eat and so produces ketones from fat stores to survive. In this case ketones would rise to very high levels in the blood and so would glucose. Because, remember the glucose can’t enter the cell and stays in the blood. This condition is called ketoacidosis and is a dangerous condition requiring medical intervention.
Ketosis, on the other hand, is a natural metabolic state and is not the same as ketoacidosis. Ketosis is simply the state of burning fat for fuel. When a body is in ketosis, ketones in the blood are only moderately elevated and the blood glucose usually lowers simultaneously.
Our hunter-gatherer ancestors were probably often in ketosis because there were shortages of food. In the case of being well fed, in our modern society a person can be in ketosis if they follow a ketogenic diet, defined as a low carbohydrate, moderate protein, high fat intake.
Being in ketosis is a perfectly normal, although not typical, state of metabolism.
So now that we know ketones are not bad, why would they be good?
- The muscles, heart, brain and liver actually use ketones as a source of fuel over glucose which has exciting therapeutic implications for many health conditions
- Following a ketogenic diet and being in sustained ketosis can result in healthy weight loss and lowered blood glucose
- Ketosis in the presence of lowered blood sugar has been observed by some clinicians to result in lowered systemic inflammation
- Increased blood ketones are known to improve brain function in conditions like dementia but also healthy people report better mental clarity while in ketosis
- Ketogenic diets are actually being used to treat cancer; it’s thought that the cancer cell can only survive with a substantial supply of glucose so switching the metabolism to run mainly on ketones starves the cancer cells of nutrition
I hope I have piqued your interest in ketones! There truly is nothing new under the sun. But what we know is ever changing. I believe that ketogenic diets will be used more and more in the near future to treat obesity and diseases of aging. That’s why you should care about “What is a Ketone?”. Wondering what exactly a ketogenic diet is? Look for a “Part 2” to dive into this.