Ketones, Ketogenic Diet, Ketosis – what does it all mean?

written by Dr. Eric Plaisance

Ketones are among the most underappreciated byproducts of human metabolism – they play a vital role in extending the survival of humans in the absence of food. Additionally, ketones have emerged as a practical and effective dietary approach to weight loss and maintenance.

Ketones produced from ketogenic diets and as supplements have also shown potential as a treatment for several chronic disease conditions, including some forms of cancer, metabolic and cardiovascular disease, and a host of neurological disorders such as Alzheimer's and Parkinson's disease.

On average, humans store approximately 50,000 calories as fat and only 2,000 calories as carbohydrates [glucose and glycogen (the storage form of glucose)]. During long periods of starvation, stored fats are mobilized to the liver and then metabolized into ketones.

The production of ketones is critical for extending survival in humans during starvation because ketones decrease reliance on muscle proteins for glucose production and provide an alternative energy source, particularly in the brain, where fats can't be used directly for energy production.

Are you wondering how to increase blood ketone concentrations without going into extreme starvation mode? There are several approaches to achieve this, and they have all shown to be quite effective. However, the most common practice is the restriction of carbohydrates in the diet. The overall concept focuses on mobilizing fats, producing ketones, and maintaining low circulating levels of the hormone insulin (the hormone that regulates glucose concentrations in the blood). To do this requires a significant restriction of carbohydrates to no more than approximately 5% of your diet while also limiting protein intake to no more than 20%. Ultimately, this translates to a diet high in fats and a metabolic state that allows the production of ketones.

The biggest argument to the ketogenic diet is that it's too difficult to maintain a healthy lifestyle because of its effects on cholesterol. However, an overwhelming majority of studies demonstrate strong palatability and potential health benefits with a high risk to reward ratio.

As in all cases, ketogenic diets are not for everyone. You should always consult with your physician and an expert in the field before starting a ketogenic diet or any diet to ensure proper nutrition.

The overwhelming majority of evidence indicates that ketogenic diets and high levels of circulating ketones are more effective at producing fat loss and maintaining lean mass (muscle and bone) than low-fat diets in animals and humans. Additionally, ketogenic diets and ketone supplements have been shown in research to improve cognitive dysfunction with dementia/Alzheimer's disease and concussion.

While there is no solid evidence in humans, ketogenic diet and ketone supplements have been promising as an adjuvant treatment in some forms of cancer in rodents, furthering the exciting potential of ketones in disease. 

Thus, it appears that in the case of ketones, the adage may hold true – "if it doesn't kill you, it will make you stronger."

Why should we be surprised that a metabolic byproduct such as ketones, which extends survival during starvation, might emerge as a strategy to do just that in the presence of food? While most of us do not face starvation frequently, the effectiveness of intermittent fasting diets and ketogenic diets should come as no surprise. Their most significant contribution may just make you a little stronger against the barrage of foods and unhealthy lifestyles that plague the world today.