A ketogenic diet, which is also known as the keto diet, is a high fat, low carb diet that has several health benefits from losing weight to reducing diabetes, heart disease, and other health conditions. Being on the keto diet turns a body into a fat-burning machine while helping people lose weight and increase energy. Learn more about the many benefits of the keto diet in the Body Reboot book and why many people are wondering why they didn't try this diet sooner. Also — did we mention that it’s possible to lose weight on the keto diet without exercising? Turn a body into a fat-burning machine, no exercise required. Learn the scoop and see why that’s the case by reading about the keto diet below.

Vitagene does an excellent job of explaining why keto is ideal for weight loss and how it can lower risk factors for many diseases.

Keto for Weight Loss

Ketogenic diets are effective for losing weight and lowering risk factors for certain diseases. While low-fat diets are traditionally recommended for those looking to shed pounds, research shows that keto is, in fact, a superior approach to weight loss.

Unlike many diets, keto will not leave you feeling hungry after eating a pre-set number of calories for the day. Keto is a satisfying and filling method of dieting. In fact, you can lose weight without tracking calories—something that deters many people from adhering to other diets.

There are several reasons why keto is more efficient than a low-fat diet, including increased protein intake. Higher protein intake is advantageous for weight reduction and metabolic health.

Quick Keto Facts

Ketosis occurs when the body is denied access to glucose, its main fuel source.

In ketosis, stored fat is broken down for energy, producing ketones.

Some people use a ketogenic diet to lose weight by forcing their body to burn surplus fat stores.

The ketogenic diet was originally developed in the 1920’s to treat epilepsy but was inadvertently discovered to offer many other health benefits.

There are multiple variations of the ketogenic diet.

Wondering how going on a low carb diet can lead to weight loss? It’s not just going on a low carb diet; it’s about having a diet that’s high in fat, as Bulletproof explains.

Less insulin equals less fat storage and more weight loss

Loading up on fat lowers your levels of insulin. Insulin is a hormone that tells your body to store energy, either as fat or glucose. The more insulin your body releases, the more fat that gets stored. Insulin also blocks leptin, the hormone that sends a signal to your brain when you’ve eaten enough to meet your energy needs. That means when you eat carb-heavy foods, you’re at risk of overeating and won’t get that full feeling before reaching for a second helping of potatoes.

You eat a ton of good fats on keto, and fat is satiating, helping you you feel full for longer. Fat also keeps your blood sugar stable, so you don’t experience energy highs and lows. When your body runs on ketones for fuel, it has a steady supply of energy in the form of body fat. When your body relies on glucose, it needs a regular hit of carbs to keep it going. Think of how you feel after eating a white bread sandwich and kettle chips for lunch. You’re ready to raid the fridge a couple of hours later. When you instead eat some grass-fed steak with butter-drenched steamed vegetables, you’ll power through your afternoon minus any distracting cravings.  

By now, you probably have a good idea of how the keto diet works. Abbott further elaborates by explaining how this high fat diet works and why, if you stick with it you not only don’t have to exercise (though, it’s not a bad thing to exercise!), but you can gain several health benefits in addition to losing weight.

How Does It Work?

When you're on the ketogenic diet, you are in a state similar to fasting – your body is using fat for fuel. Normally your body gets energy from readily available carbohydrates, but on a keto diet, your carb intake is slashed. “When carbs are available, the body will naturally turn to them for energy instead of using dietary fat or stored body fat,” explains Pam Nisevich Bede, RD, MS, a dietitian with Abbott.

However, without regular replenishing of carbohydrates, the body begins to break down fat for energy, resulting in the formation of ketones. Ketones can eventually be used by the body for energy.

The move from carb to fat fueling is marked by an adaptation phase. This phase can come with some lethargy and other symptoms as your body adjusts (we discuss this more later) but you'll start to notice weight loss as well as more steady energy and less hunger. “This can be a hard shift for someone who's been fueling with bagels and pasta their entire life, but after three to five weeks, the body adapts,” Bede explains.

What You'll Be Eating

The key to keto is knowing what's in your food. “On a standard diet, most people consume approximately 50-55 percent carbohydrates, 20-25 percent protein and 20-25 percent fat,” says Bede. “With a keto diet, the breakdown is approximately 75 percent fat, 20 percent protein and 5 percent carbohydrates.” For example, a woman who weighs 150 pounds and is moderately active is recommended to eat 25 grams of carbs (think one medium sized apple!), 86 grams of protein (a little over three 3 oz chicken breasts) and 189 grams of fat (hello, avocados and nuts!) per day on the keto diet.

Perfect Keto explains what ketones are and how they work while you’re on the keto diet:

Ketones are the metabolic fuel produced when your body shifts into fat-burning mode.

Glucose and ketones are the only energy sources used by the brain. Think of ketones as the auxiliary power source of your body.

Before the advent of agriculture, when our ancestors were hunter-gatherers, they fasted regularly. When food was scarce, they didn’t have a choice but to wait for an opportune time to hunt for food and cook it.

They had a very low intake of carbs and protein and thus were unintentionally running on ketones. Converting stored fat into energy is hardwired for our survival and a natural part of human existence.

Your body burns fat to use and produce ketones whenever glucose sources are low or depleted, such as:

during fasting

after prolonged exercise

when you eat a ketogenic diet.

Lipase (an enzyme responsible for fat breakdown) releases stored triglycerides (fats). These fatty acids go to your liver and your liver turns them into ketones.  

There are three types of ketone bodies:

Acetoacetate – During the breakdown of long- and medium-chain fatty acids for energy, acetoacetate is produced first.

Acetone – Spontaneously, acetone is also produced as a by-product of acetoacetate. Both of these ketone bodies, when not used, spill into your urine and breath, making urine and breath testing a promising measurement of whether or not you’re going into ketosis. More on this below in How to Test Ketone Levels.

Beta-hydroxybutyrate (BHB) – Not technically a ketone but a molecule. Its essential role in the ketogenic diet makes it count as the important ketone body. BHB is synthesized by your liver from acetoacetate. BHB is important because it can freely float throughout your body in your blood, crossing many tissues where other molecules can’t. It enters the mitochondria and gets turned into ATP (adenosine triphosphate), the energy currency of your cells. BHB = ATP = energy!

Now that you know what ketones are and how ketosis works, you probably want to know why you should consider eating a ketogenic diet — the diet that promotes ketosis.

You may be curious how the keto diet works if you decide to work out (which we recommend you do even though you can lose weight without it), and Men’s Journal does an excellent job of summarizing how the keto diet works for those who choose to stay active:

So how does the ketone diet affect my gym routine?

Good question! First, you need to know that your body has three basic ways of burning fuel, called metabolic pathways:

– phosphagen (maximum energy in the shortest amount of time; think powerlifting)

– glycolytic (for short bursts of energy, like a 100-meter sprint)

– aerobic (long-term exercise, like a 40-mile bike ride at a moderate pace; also the most efficient form of energy generation)

Here’s why that matters: Ketosis is strictly an aerobic form of generating energy, which means that your body needs oxygen to make it work. If you’re going for multiple-hour-long bike rides, then your body should have no problem getting enough oxygen to your muscles, and it can rely on ketosis to get the energy it needs.

It’s true that the keto diet can help you reach your weight loss goals without having to exercise. That doesn’t mean you shouldn’t exercise, however! But it’s nice knowing there’s a way to improve your health without having to work out like crazy. To learn more about keto, simply help us cover shipping and receive the Body Reboot book free.

Sources: Vitagene, Bulletproof, Perfect Keto, Men’s Journal, Abbott