The Keto Diet: What It Is, Why It’s Popular, and How You Can Start

The ketogenic diet has been the most popular diet for the past two years, and it’s still trending upwards. Critics may call it a fad diet, but science shows it offers unique health benefits that other styles of eating do not.

Learn what distinguishes keto from other diets, the top reasons people go keto, and the best way to begin if you want to try it out.

What Is the Keto Diet?

The keto diet or ketogenic diet is a very-low-carb, high-fat diet with moderate protein. Ketogenic means “ketone-producing.”

When you go cut carbs and go keto, your body goes into a state of ketosis and produces the following ketones:

Ketones are energy molecules your liver makes as you metabolize free fatty acids (FFAs) in the absence of carbs. Because you aren’t eating sugar or other carbohydrates on keto, your body relies on ketones and FFAs for fuel.

While stored fat and dietary fats are efficient fuels for your muscles and organs, your brain must rely on ketones in the absence of glucose (a simple sugar).

In a nutshell, the keto diet turns your body into a fat-burning machine, which alters your metabolism, reduces inflammation in your body, and improves your insulin sensitivity. As a result, keto offers numerous health benefits.

What’s the Difference Between Keto and Low-Carb?

While the ketogenic diet is one type of low-carb diet, not all low-carb diets are ketogenic. In other words, not all low-carb diets (like Atkins or some paleo diets) will necessarily put you into a state of ketosis.

In the nutrition world, most people consider diets with less than 100 grams of carbs per day “low-carb.” Other people would define the cutoff point at 50 grams of carbs.

Although low-carb diets have many perks, most people need to eat far fewer than 100 grams of carbs per day to attain ketosis.

How Many Grams of Carbs Can You Eat on Keto?

The best way to determine how many carbs you can eat is to measure your ketone levels. Testing is only way to know for sure that you’re in ketosis.

The cheapest method is urine testing strips, or alternatively  you can test your blood ketone levels, which is more accurate.

Everyone has an upper limit when it comes to daily carbohydrate intake, but factors like your body weight, fitness, exercise habits, age, and health history can all affect your carb allowance.

As a rule of thumb, most people can stay in ketosis by eating no more than 25-30 grams of net carbs each day. Some people can get away with up to 50 grams.

What Else Can You Eat?

Because keto requires extreme carb restriction, the vast majority of your calories come from protein and fats.

The most popular form of keto uses the following macronutrients:

On the other hand, the following version is used for treatment of epilepsy (and in many studies of the ketogenic diet):

As you can see, the medical version of keto used for epilepsy is more strict and has less protein. However, for people without epilepsy who want to improve their health and wellness and lose weight, the popular version is the best choice.

Keto Food Selection

Unless you think “dirty keto” is a smart idea (it’s not), the majority of your calories need to come from whole foods.

For carbs, the best options are high-fiber, low-carb fruits and vegetables. Think avocados, berries, and leafy greens.

The top pick for protein sources on keto are animal products like beef, eggs, pork, and fish. Aim for grass-fed, pastured, free-range or wild-caught, and organic selections whenever possible.

(Note: going keto if you’re a vegan or a vegetarian is challenging, but possible. In that case you would rely on protein sources like full-fat tofu, tempeh, and—for vegetarians—pastured eggs.)

Your dietary fat can come from a combination of plant and animal fats. Butter, extra virgin coconut oil, extra virgin olive oil, medium-chain triglycerides, nuts, bacon, lard, and tallow are all fantastic choices.

Reasons People Follow the Keto Diet?

The primary reason to follow the keto diet is the same as most diets: to lose weight or help you maintain a healthy weight.

But unlike virtually every other diet out there, keto allows most people to eat ad libitum (to fullness) and still lose weight. That’s because all the fat fills you up, but still creates a caloric deficit.

There’s also solid research showing that keto improves your cholesterol levels, reverses insulin resistance associated with metabolic syndrome and type 2 diabetes, slows cognitive decline in aging, reduces inflammation associated with heart disease and cancer, and treats epileptic seizures that don’t respond to drugs.

How to Get Started on Keto

To get started on keto, you need to stock up on whole food protein sources, healthy dietary fats, and keto-friendly fruits and veggies. Most people will also do better if they remove processed and refined carbs from their pantries (consider donating rather than trashing them).

You don’t need to count calories to succeed on the ketogenic diet, but you should count carbs and measure your ketone levels, especially at first.

If possible, purchase urine ketone test strips or a blood ketone meter. Urine strips are slightly less accurate, but cheaper than a blood ketone meter. Either option is better than nothing.

It takes most people a few days to a week to achieve ketosis. A meal with too many carbs will kick you out of ketosis. If you aren’t attaining ketosis, you may be eating hidden carbs, or your body might be stubborn—take a closer look at your macros just to be sure you aren’t eating too many carbs, then give it some time.

Some people experience “keto flu,” which can include symptoms like sweating, nausea, headaches, and lethargy. If the keto flu lasts more than a week, speak to your doctor. It could be something else that requires medical attention.

After two to four weeks on keto, you should be over the transition phase: your body should be in ketosis and better-adapted to burning fat and you’ll begin to notice increased clarity, better energy levels, and reductions in your appetite.

All Keto Diet Articles