Part 1: Beginner’s Guide to the Ketogenic Diet

The ketogenic diet has exploded in popularity. The diet changes the body’s preferred fuel source from carbs to fats. In this multi-part post, I’ll go over what you need to know before trying the ketogenic diet. The first part of this post will cover the basics—what is the ketogenic diet and how does it work. 

What Is a Ketogenic Diet?

A ketogenic (or keto) diet is a high fat, moderate protein, and low carb diet. It forces the body to burn fat as its primary source of energy instead of glucose (from those tasty carbs we love).

Ketogenic Diet Types for Treatment of Disease

The ketogenic diet was designed in 1923 to treat epilepsy. The original diet used a macronutrient ratio of 90% fat, 6% protein, and 4% carbs. There are five versions of the diet that have been published as effective treatments for disease. They all follow the same template of high fat, moderate protein, and low carbs, but the ratios are different. Here are the five types listed by the Charlie Foundation:

  Classic Keto

Classic Keto

  Modified Atkins

Modified Atkins

  Modified Keto

Modified Keto

  Low Glycemic Index

Low Glycemic Index



Ketogenic Diet Types for Weight Loss or General Health

When the diet is used for weight loss or general health, the macronutrient ratios aren’t as strict as the original diet. But they still stick to the high fat, moderate protein, and low carb approach. A few variations of the original diet include:

  • Standard ketogenic diet: this is the most common version that people are familiar with. It typically contains 75% fat, 20% protein, and 5% carbs.
  • Cyclical ketogenic diet: this is an advanced approach. You cycle between a low-carb ketogenic diet and days of carb refeeds. For example, you stick to the ketogenic diet for five days, then have two higher-carb days. This is mainly used by bodybuilders and athletes who want to maximise fat loss while still building muscle or performing high-intensity exercise.
  • Targeted ketogenic diet: this is another advanced approach. You follow a ketogenic diet but add fast-digesting carbs (around 25-50 g) 30-60 minutes before a workout. The carbs are burned without disrupting ketosis for too long.
  Image source:  BioKeto

Image source: BioKeto

How We Convert Food to Energy

Most of us are sugar burners. This means that we get the majority of our energy from carbs.

When we eat carbs or excess protein, they’re broken down into a simple sugar called glucose. Glucose provides the cells of our body and brain with quick energy, so it’s our preferred fuel source. Glucose is especially important for fuelling brain function.

How We Store Excess Food as Energy

When we consume more energy than we need from carbs, fat, and protein, the body stores the extra energy. Our bodies are always preparing for a famine. This is why we store body fat—it’s kept us alive and evolving when food has been scarce.

The body stores extra energy in two ways:

  • Glycogenesis: when you’ve eaten enough carbs to meet your immediate energy demands, the remaining glucose is converted to glycogen for storage. Glycogen is stored in the liver and the muscles. Liver glycogen is used to maintain blood glucose levels between meals. Muscle glycogen can only be used inside the muscle for energy.
  • Lipogenesis: if your stores of muscle and liver glycogen are full, the extra glucose gets converted to fat and stored. Unlike our limited ability to store glycogen, fat stores are almost unlimited. That’s why people can live for months without food. Even the leanest person you know has enough fat to keep them going for a long time without food.

When calories are restricted or you fast, your body frees energy from glycogen and fat stores. But when glycogen runs out something interesting happens . . .

How and Why Does Ketosis Happen?

The body has limited stores of glycogen in the liver and muscle. After a few days of fasting or restricting carbs, they’re all used up. When glycogen stores run out, fat is converted into an alternate fuel source known as ketones. When this happens, you are in ketosis.

But why does the body create ketones when it can use our near-endless fat stores for fuel?

Fat can be converted to energy and used by many cells in the body, but it can’t be used as energy for brain cells. Fats are converted to energy too slowly to power our brains. This is why glucose is our preferred fuel source.

We produce ketones as a survival mechanism when carbs or calories are restricted. It’s our backup system that keeps our brains functioning. If we didn’t produce ketones, our brains wouldn’t have enough energy when carbs got low. Our bodies would be forced to break down muscle tissue to create glucose to power our brain. So, we’d be hungry, not able to think, and weak from muscle breakdown—in other words, up shit creek without a paddle.

Here’s a simplified graphic showing the difference between a diet that gets energy from carbs and a ketogenic diet.

  Image source:

Image source:

Part 2: Benefits and Side Effects of the Ketogenic Diet

The ketogenic diet is a big topic. So, this post will be a multi-part series where we take a deep dive into all things ketosis.

Tune in next week and I’ll cover the benefits and side effects of the diet. In Part 3, I’ll show you how to put your body into ketosis.

Do Something—Anything!

Don’t just consume information. If you’ve read this far, I’m assuming you find this post useful. You’ve now got two choices: 1) close the screen and think ‘that’s nice’ and move on with your day. Or 2) if you’re considering trying the ketogenic diet, commit to reading the next few week’s posts to learn the basics. They’ll give you the information you need to take action. Remember: decision creates action. Action creates results.

I Need Your Help

I’ve also got a huge favour to ask of you. No, I don’t want your money. But will happily accept it! I’m trying to get this blog off the ground and I can’t do it without your help. Simply sharing this post on social media (you’re so close to the share buttons—look down below) or emailing it to a friend makes a HUGE difference in my life. In return, I promise we can be best mates and you can reach out anytime. Seriously. If you need help with any health, fitness, or Jedi Knight goals you can contact me here.

You can also share some love by adding a comment below. Let me know if you’ve tried the ketogenic diet or a high-fat diet. Did you love it? Hate it?

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