Unless you’ve been living under a rock for the past fifteen years, you’ve heard of the keto diet.

In the simplest sense, the keto diet (also called the ketogenic diet or “keto” for short) is a weight loss strategy that emphasizes little to no carbs, high fat and moderate amounts of protein.

In this article, we’ll examine the benefits of the keto diet and if it’s an appropriate eating plan to follow for athletes and non-athletes alike.

Ketosis: the secret of the keto diet

To understand the keto diet, you need to understand how your body processes food for energy.

Our bodies have two sources of fuel: glycogen and ketones.

Most of the time, we use glycogen. In fact, with the advent of grocery stores and our modern diet, it’s rare that anyone is involuntarily in a state of ketosis.

Once our glycogen stores are depleted, our body transitions to using ketones as fuel.

There’s more to it than that, but that is how the process works in the simplest sense. How does this relate to fat loss?

As we mentioned earlier, once your body uses up all its glycogen (a form of sugar the body creates from carbs), it switches to using ketones for energy. This is known as being “in ketosis.”

Once you’re in ketosis, your body is burning exclusively fat for energy. And if you haven’t eaten any dietary fat recently, then your body will turn to the fat stores that your body has accumulated over the years.

The WRONG Way to do the Keto Diet

This is where most people go wrong when trying to live on a ketogenic diet.

While it’s true that your body will switch to burning ketones for fuel instead of glycogen, this in and of itself has nothing to do with fat loss.

Yes, your body will burn fat, but if you are treating yourself to sticks of butter and raw bacon grease, then your body will have plenty of potential fuel to use.

Furthermore, some new practitioners of the keto diet are guilty of having a selective memory when it comes to the amount of calories in a gram of fat (9) vs a gram of carbs (4).

Sadly, some people seem to understand the keto diet as, “you can eat whatever you want as long as you don’t have carbs!”

This is a huge mistake.

Just because your body will switch to burning fat as fuel instead of carbs, at the end of the day if you are stuffing yourself on too many calories, regardless of whether it’s from fat, carbs, or cardboard, you are going to gain weight.

The laws of physics still apply to you even if you are the ketogenic diet.

If you are trying to lose weight, it’s important that you keep your calories in check while doing the keto diet.

That said, it’s likely that once you cut out carbs completely, you’ll feel less of a desire to snack.

Let’s face it: carbs make the best snacks. While you may love peanuts and beef jerky, how much of them can you realistically eat? Probably not that much.

But put a fresh box of Oreos in front of someone who has a history of binge eating, turn on their favorite TV show, and watch them perform a feat of magic as the Oreos disappear in record time.

Controlling Insulin: the Keto Diet’s REAL Secret Weapon

We explained earlier how the ketogenic diet allows your body to switch from using carbs to fat as a source of fuel. But this is only half of the magic of the keto diet.

The second – and arguably the more important – half is that you will drastically improve your body’s level of insulin sensitivity.

Insulin is a hormone that your body releases that switches your body into “anabolic” mode. Contrary to popular belief, if your body is anabolic it doesn’t mean that you are going to blow up like Arnold Schwarzenegger after doing a few hex bar deadlifts.

Being anabolic just means that your body is in storage mode. You are building muscle and storing fat. This is as opposed to being “catabolic” – where your body is burning fat and potentially breaking down muscle.

The difference between each of these comes down to one thing: insulin.

When your insulin is high, you will build muscle and store fat. And I have bad news for those of you who are somehow reading this and not exercising regularly: without exercise, you are ONLY going to be storing fat.

So what does this have to do with the keto diet?

Well, insulin is released at a fast rate depending on how high the food ingested is on the Glycemic Index. In a general sense, this is a measurement of how sweet a certain food is.

What kinds of foods are sweet? Carbs.

What kinds of foods AREN’T sweet? Things that aren’t carbs.

Putting it all together, cutting out carbs means less opportunities for your insulin levels to spike.

A typical keto diet of steamed veggies and fatty cuts of meat is unlikely to cause your insulin to rise by any meaningful amount.

This, combined with your body’s newfound ability to burn body fat as fuel, could theoretically lead to a rapid reduction in bodyfat.

There are also other benefits. As Peter Attia (a medical doctor who I follow closely and have learned a lot from) points out, there are a great number of health benefits that can be achieved by reducing your insulin area under the curve (or insulian AUC).

Think of insulin AUC as the area under an insulin-time chart, where insulin is on the y-axis and time is on the x-axis.

Don’t Let Keto Flu Stop You From Trying the Keto Diet

So far, the keto diet sounds pretty amazing, doesn’t it?

You lose weight, have license to eat more high-fat foods, and get to control your insulin levels. What’s the downside?

Two words: keto flu.

In a perfect world, our bodies would transition from using glycogen to ketones as energy seamlessly. But everything comes with a price.

And in this case, the price is up to three weeks of headaches, low energy, irritability, and overall crankiness.

As I mentioned earlier in the article, most human beings are unlikely to find themselves in ketosis involuntarily for any reason. Carbs are everywhere and we naturally want to eat them to varying degrees as part of every meal.

As a result, your body is used to burning glucose as energy almost exclusively. It’s likely that it’s rarely, if ever, had to burn ketones as energy instead.

When you suddenly pull the rug out from under it and deprive it of foods that it can easily break down into glycogen, it’s going to be very cranky.

Our bodies can’t speak, but if they could, they would say something like,

“Hey! Why aren’t you feeding me what you normally feed me? How do you expect me to do all the stuff I normally do to keep you alive? Give me carbs!”

Unfortunately our bodies can’t speak.

But what they can do is give you a nasty headache, make your face flush for no reason, and just in general make you feel like crap until either you give in and eat some french fries or your body gives in and starts burning fat as fuel.

All that said, if you have a considerable amount of weight to lose, don’t let keto flu stop you. Getting into ketosis is an extremely efficient way to drop excess weight in a hurry, while still behaving in a healthy way.

Like almost everything else in the fitness world, one size does not fit all. Try the keto diet out and see if you like it. I use a Keto Mojo ketone meter to track my ketones over time and find that my athletic performance and mental focus have both improved while being in ketosis.

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