What Is the Keto Diet Plan?

Finally: A simple guide to understanding the fad diet everyone's talking about.


If you're hearing more and more about the keto diet plan for weight loss, it's not your imagination: Keto was the number one searched diet term on Google in 2018. So, what is all the hype really about? Read on for a crash course on the basics of keto, and an answer to the question, “Can I really eat bacon and butter and lose weight?”


What is the keto diet plan?

"Keto" is shorthand for the ketogenic diet, an ultra low-carb eating plan. In short, the approach involves eating lots of dietary fat, a moderate amount of protein, and very little carbohydrates. It's not exactly a free-for-all: Ideally, a keto dieter gets about 70 to 80 percent of their daily calories from dietary fat; about 10 to 20 percent from protein; and about 5 to 10 percent from carbohydrates[i].

Although fat contains more calories per gram than carbohydrates and protein, and eating more calories than your body needs could ultimately lead to weight gain, eating a fat-focused diet can lead to weight loss when the program is closely followed. Initially, weight loss stems from water loss that occurs in response to the dramatic reduction of carbohydrate intake. Eliminating lots of foods you typically eat (in this case, carbs) can also lead you to consume less overall, which can contribute to additional weight loss. 

There is some evidence that getting most of your calories from fat can lead to fat loss, in particular: Although the cells in your body typically prefer to use glucose (sugars derived from the carbs you eat) as a source of energy[ii], when you eat a very low carb diet that's rich in fats, your body burns fat for energy instead. The process occurs in the liver, which releases a byproduct known as ketone bodies, an alternative source of energy [iii]. 

Whether you are eating a high or low-carb diet, you are only going to lose weight when you consume fewer calories than your body burns.


Is the keto diet plan new?


Despite all the recent buzz, the keto diet plan is not new. This type of diet was first developed in the 1920s to treat epilepsy in children[iv]. It's gained popularity in the weight-loss space more recently.


Does the keto plan help you lose weight for good?


Not necessarily. Remember how we talked about water loss? Once you eat more carbs than the keto diet plan allows, the water weight may return. And most people can't—or wouldn't want to!—avoid foods that contain carbs for life.


What foods can you eat on the keto diet plan?


On the keto diet, most carbs like bread and pasta plus fruits and many vegetables make up a significantly smaller portion of your diet compared to the average eating plan. 

A breakdown of some of the foods you’d eat on keto:

Fats: 70-80% Protein: 10-20% Carbs: 5-10%

Oils – coconut, olive, etc.
Animal fats – duck fat, lard, tallow, etc.
Pork rinds

Organ meats
High-fat dairy
Deli meat
Fatty fish

Leafy green vegetables (these are the most keto-approved veggies)
Berries and other low-sugar fruits


For a typical 2,000 calorie per day diet, this translates to about:

  • 165 grams of fat
  • 75 grams of protein
  • 20 to 30 grams of carbs[v]

Does it look healthy to you?


RELATED: How the Ketogenic Diet Compares to WW Freestyle


What kind of carbs can you eat on the keto diet plan?


For the keto diet plan to work properly, carbohydrate intake has to be dramatically reduced. For the most part, this means eliminating pasta, bread, oatmeal, potatoes, most fruits and many veggies from your daily diet—meaning you won't appreciate these foods' nutritional benefits. 

Take for example the broccoli salad below: It looks healthy, right? It’s also got 33 grams of carbs which would exceed the 30 grams you're able to eat each day on the keto diet.


Chopped Broccoli and Cranberry Salad with Egg



Turns out, carbs are hidden in lots of nutritious foods like whole wheat bread (47 grams of carbohydrates per slice), bananas (37 grams each) and oatmeal (27 grams per cooked cup). 

Is the keto diet plan hard to follow?

While many have found the keto diet to be helpful during a focused period of weight loss, studies have shown keto can be restrictive and hard to follow over the long term. Plus it can be heavy on red meat and other fatty foods that are increasingly considered to be unhealty[vi].  

Is the keto diet plan safe?

Following the keto diet means increasing the amounts of fats in your diet. Keto does not differentiate between the quality of fats (saturated versus unsaturated) and only mandates that you eat a lot of it. There are “good” fats and “bad” (a.k.a. saturated) fats; foods high in saturated fat come with known health risks including increased risk of heart disease[vii].

RELATED: The Difference Between "Good" and "Bad" Fats 

Keto does not align with the Dietary Guidelines for Americans for 2015-2020, which emphasizes eating fruits, vegetables, and whole grains for optimal health.

Experts agree that the best eating plans include a wide variety of foods and can be followed for the long term—meaning they don’t require you to eat from a list of ‘approved’ foods. Some people have found that keto works well for them, and others have found it can be hard to sustain.

If you have pre-existing liver or kidney conditions, heart disease or diabetes, you should seek the advice of a physician before undertaking any significant changes to your diet.

RELATED: The #1 Weight Loss Program