Accumulating evidence suggests that any athletically-inclined individual can benefit from a shift of energy metabolism toward the utilization of ketone bodies. However, the good news does not end there. Clinical research evidence on exogenous and physiological ketones suggests they particularly helpful for patients/clients living with Type-2 diabetes, congestive heart disease, depression, IBS, and many other ailments. Read on to find out the numerous ketone applications that may improve health conditions.

What Is Ketosis?

Data on both human and rodent experimentation have identified an individual’s average serum ketone body concentration as lying between 0.1 to 0.5 mM; thus, a true state of ketosis reflects serum concentrations above 0.5 mM. Conditions that result in carbohydrate deprivation/low glucose availability, such as intermittent fasting or adopting a ketogenic diet, typically pair with such elevated serum ketone numbers.

The Heart on Ketones

Owing in large part to the enormous requirement for continual replenishment of energy stores, our organs — the heart in particular — possess an uncanny ability to utilize any available carbon-based substrate. To this end, they can metabolize exogenous fatty acids, glucose, lactate, amino acids, and ketone bodies to produce energy.

During the progression of congestive heart failure, the ailing heart can actually reduce glucose oxidation, shifting to increasing ketone metabolism. Although previously considered to be a relatively minor substrate, ketone body oxidation contributes up to 20% towards cardiac energy metabolism. Research suggests that the normal healthy heart generates approximately 60-80% of its energy requirements from fatty acids, with approximately 10-20% from glucose. The beneficial ketone applications for heart failure are certainly worth mentioning to clients with heart issues.

Navigating the Ketogenic Highway

In order for the body to utilize fat as an energy source, referred to as entering ketosis, it must significantly deplete existing glycogen stores. Such a ketotic state evolves through severe restriction of dietary carbohydrates; some individuals following a strict ketogenic meal plan seek to consume less than 5% of their daily calories from carbohydrates. Without readily available glycogen, the body seeks alternate forms of energy.

Certain unique metabolic pathways within the body that access fatty acids (typically from adipose tissue) lead to their breakdown into ketone bodies. Through this beta-oxidation process, the ketone bodies enter the Krebs cycle and ultimately produce adenosine triphosphate (ATP), the body’s energy units. Utilized in this manner, ketones serve as an efficient fuel for the entire body, including the brain.

In Consideration of Ketone Supplements

Exogenous ketone supplementation can offer the serious athlete many benefits, including improved performance, efficient weight loss, cognitive improvement, and a lessening of sports-induced inflammation.  Ketones tend to spare lean muscle mass, as the body instead begins to use fat stores for energy.

As trainers, our focus typically revolves around those individuals with a keen interest in performance and athleticism. However, even for the general public, supplementation of exogenous ketones shows promise in other arenas. Studies show that cancer cells cannot make effective use of ketone bodies, unlike most other tissues in the body. In fact, dietary ketone supplementation increases the survival rates of cancer-riddled mice by as much as 70%.

Exogenous ketone supplementation also causes a significant dip in circulating blood glucose levels, brought about by a sharp increase in insulin sensitivity. Scientists in this field of research have started to consider exogenous ketones as a potential therapy for Type-2 diabetics. Additional work in this area will most likely reveal more answers as time goes on.

MCTs: Chains of 6-10 Carbon Molecules

When embarking upon a true ketogenic meal plan, individuals replace the bulk of their carbohydrate calories with those derived from healthy fats. Dietitians who work with clients interested in a ketogenic lifestyle suggest a daily macronutrient breakdown of 70-80% fats, 5-10% carbohydrates and 10-20% protein. For a 2000-calorie diet, this translates to approximately 165 grams fat, 40 grams carbohydrate, and 75 grams protein.

Such narrow parameters prove challenging for many, especially since the body typically utilizes carbohydrates (in the form of glucose) for energy. During the transition, many individuals experience what some refer to as “keto flu”: fatigue, lethargy, general malaise. This, too, deters many people. However, after about 7-10 days, the body rebounds and adapts to utilizing fats as its primary energy source.

Caprylic acid, a medium-chain triglyceride (MCT), rapidly breaks down from its 8-carbon fatty acid chain configuration into ketone bodies, especially when an individual fasts or rigorously depletes calories/carbs. In 2017, studies revealed that caprylic acid possesses the highest net ketogenic effect of any medium-chain triglycerides. In short, MCTs represent fats that burn like carbohydrates, particularly effective when an athlete seeks to restrict carbs prior to an event favoring a very lean physique (i.e., bodybuilding competitions).

MCTs and Health Benefits

Caprylic acid has also demonstrated the ability to maintain “good” (HDL) cholesterol levels while improving the clearance of the so-called “bad” LDLs in mice fed a high-cholesterol diet. A 2008 study published in the journal Lipids also identified caprylic acid as a modulator to plasma cholesterol levels.

The same anti-inflammatory properties attributed to medium-chain triglycerides may also help support the gut microbiome. Individuals who make caprylic acid and other MCTs an integral part of their nutrition program have reported benefits in addressing several digestive disorders, including irritable bowel syndrome (IBS), gastric emptying, and lipid malabsorption. To date, little research has been done to uncover and explain the mechanisms behind these effects. However, some evidence does suggest that caprylic acid can target Interleukin 8 (IL-8), an inflammation-promoting glycoprotein frequently associated with Crohn’s disease.

Guiding Clients Toward Appropriate Ketone Applications

Our clients with comorbidities or health concerns may inquire about ketogenic diets or ketone applications for their health issues. Numerous studies suggest that the administration of exogenous ketone supplements and the metabolic changes they bring on might pave the way for potential therapeutic treatment of central nervous system disorders, oxidative stress, and cardiac complications, as previously mentioned.

For the many individuals who find the stringent regulations of a ketogenic diet challenging to maintain, such exogenous supplementation can offer a gentler way to reap the benefits of ketosis.

If you have clients seeking to embark upon the ketogenic lifestyle, even temporarily, you can now shed some light on the process involved, the highly coveted benefits, and the long-term manifestations in improved health.


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Cathleen Kronemer

Cathleen Kronemer is an NFPT CEC writer and a member of the NFPT Certification Council Board. Cathleen is an AFAA-Certified Group Exercise Instructor, NSCA-Certified Personal Trainer, ACE-Certified Health Coach, former competitive bodybuilder and freelance writer. She is employed at the Jewish Community Center in St. Louis, MO. Cathleen has been involved in the fitness industry for over three decades. Feel free to contact her at She welcomes your feedback and your comments!