Ketone Bodies (Definition, Purpose, and Studies)

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Ketone Bodies (Definition, Purpose, and Studies)

If you’re new to keto, you’re probably seeing a ton of content around ketones, ketone bodies and utilizing them for fuel.

However many of the sources are complex papers that can be difficult to read and hard to understand.

So what are these ketone bodies that everyone is talking about? Let’s break it down.

What Are Ketone Bodies?

Ketone bodies are molecules that are water-soluble that contain ketone groups from fats. They are a source of energy you body can utilize when carbohydrates are not an option. Testing for ketone bodies has become popular with the advent of diets like paleo, low carb, and (obviously) the keto diet. It has also spawned interested in supplement exogenous ketones (which we’ve reviewed here and will touch on later).

How are Ketone Bodies Formed?

Ketone bodies are formed by the liver in three situations:

  1. Caloric restriction (or fasting)
  2. Low-carbohydrate or restrictive diets
  3. Intense exercise

Ketones are also produced in type 1 diabetes subjects.

Ketone bodies themselves are a result of a gluconeogenesis in the liver that’s commences once glycogen stores in the muscles have been depleted (within 24 hours of fasting).

Because of this, ketones can be a viable source of energy . Also, the fact that your body is using stored fat for energy rather than carbohydrates is part of the reason that the keto diet has become so popular for fat loss.

How Your Body Uses Ketone Bodies as Energy

Your body can utiilize ketones in a few specific ways. While you can supplement with exogenous ketones, your body primarily uses ketones for fuel while in ketosis.

Your brain is the primariy consumer of ketones – although your heart can utilize them as fuel in specific situations.

Typically your brain utilizes ketones as fuel when glucose is not available (or less available than it’s accustomed to). One study shows that after 72 hours of fasting, your brain is utilizing 25% of it’s energy from ketone sources.

Studies around the limits of ketone consumption has been limited by the ethical questions around testing an experiment like this.

Other Questions on Ketone Bodies

Other frequently asked questions about ketone bodies:

Where are ketone bodies made?

Ketone bodies are produce by the liver

What is ketone bodies synthesis?

Ketone body synthesis is the process of ketone body creation. 

Do Ketone Bodies Smell?

Ketones have a distinct smell to them – which is often noted in persons new to keto. The smell has been described as fruity or nail polish remover (because of the smilier compounds). This is one of the major changes that newbies to keto will notice immediately.

Sources & Citations

Other sources & citations for ketone bodies

Other Keto Related Resources

→ Try our keto meal plans

→ Keto vs. Low Carb comparison

→ Paleo vs. Keto comparison

→ What is Keto Headache

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Joel Runyon
Joel Runyon is the founder of Ultimate Meal Plans. Joel is an ultra endurance athlete and entrepreneur. He's also the founder of Ultimate Paleo Guide, MoveWell and is the founder of IMPOSSIBLE ® - a lifestyle performance brand helping people push their limits in fitness and life.

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