How Do You Follow the Ketogenic Diet?

The ketogenic (keto) diet is a very low-carbohydrate (carb), high-fat diet. It is often used for medical conditions such as epilepsy and other health concerns, including weight loss and blood glucose control. Learn which foods to eat and avoid on a keto diet.

Principles of the Ketogenic Diet

The ketogenic (keto) diet was first used to help treat children with childhood epilepsy. Today, the keto diet is often advertised and used for weight loss. The main principles of the diet include eating very few carbohydrates, moderate protein, and high amounts of fat. 

The overarching goal is to reach a state of ketosis by starving the body of its preferred energy source: glucose (sugar) from carbohydrates. In ketosis, the body uses ketones, compounds produced from the breakdown of fat in the liver, as its primary energy source instead of glucose.

The classic keto diet for children with epilepsy allows for 10 to 15 grams of carbohydrates per day and 1 gram of protein per kilogram (2.2 pounds) of body weight, with the remaining calories coming from fat.

Most people looking to follow a keto diet for weight loss are allowed fewer than 20 to 50 grams of carbs per day. If the diet is strictly followed, it usually takes a few days for the body to reach a state of ketosis. Keep in mind that eating too much protein can disrupt ketosis.

Keto Diet Food List

Fat is the main macronutrient consumed on a keto diet, so it must be consumed at each meal. Protein foods are also encouraged in moderation. 

Foods allowed on the keto diet include:

• Butter
• Lard
• Cocoa butter
• Plant oils, such as olive, avocado, palm, and coconut oils
• Hard cheeses, such as cheddar, parmesan, and asiago
• Nuts, such as walnuts, almonds, macadamia, and pecans
• Seeds, such as flax, sesame, hemp, pumpkin, and sunflower seeds
• Avocado
• Olives
• Coconut meat
• Beef
• Poultry
• Pork
• Bacon
• Fish
• Eggs
• Tofu
• Non-starchy vegetables, such as leafy greens (lettuce, spinach, kale, bok choy, Swiss chard), broccoli, cauliflower, asparagus, onion, cucumber, mushrooms, peppers, garlic, celery, summer squash, and Brussels sprouts
• Dark chocolate (90% or higher cocoa solids)
• Unsweetened almond, cashew, coconut, or flax milk
• Unsweetened coffee and tea 
• Unsweetened vinegars and mustards 
• Herbs and spices
• Some fruits in small portions, such as berries
• Some full-fat dairy, such as heavy cream, cream cheese, or whole-fat Greek yogurt, may be allowed in small portions

Foods to Avoid

Foods high in carbohydrates are not allowed on a keto diet. These include:

• Grains, both whole and refined, such as flours, bread, tortillas, pasta, rice, cereal, oats, and quinoa
• Starchy vegetables, such as potatoes, winter squash, corn, and peas
• Most fruits and all fruit juices
• Legumes, including beans and lentils
• Milk, flavored yogurt, and ice cream
• Sugar-sweetened beverages
• Sugar-sweetened condiments and spreads
• Regular beer and alcoholic beverages with added sweeteners

Benefits

Aside from helping manage epilepsy, the keto diet has been shown to aid in weight loss. Especially in the beginning period of the keto diet, weight loss tends to be fairly rapid.

1. Weight Loss

Studies have shown that the keto diet results in faster weight loss than a reduced-calorie diet. While the keto diet may initially result in greater weight loss, there seems to be no significant difference in long-term weight loss between a low-fat diet and a low-carbohydrate diet (such as the keto diet).

2. Blood Glucose

Carbohydrates directly impact blood glucose levels. Eating very few carbohydrates can help lower blood glucose and insulin levels, improving insulin sensitivity (the body’s response to insulin, which allows cells to take in glucose from the blood for energy). Because of this, following a keto diet may help improve blood glucose management in people with type 2 diabetes.

3. Cholesterol and Heart Health

The keto diet’s effects on cholesterol levels and heart health remain controversial. Some studies show that it can have beneficial effects in lowering triglycerides and increasing high-density lipoprotein (HDL) “good” cholesterol. In contrast, some studies found that low-density lipoprotein (LDL) “bad” cholesterol remained unchanged or increased.

Overall, more long-term studies are needed to determine whether a keto diet benefits heart health.

Is the Keto Diet Healthy?

The ketogenic diet might be an option for treating certain medical conditions, speeding up initial weight loss, and aiding blood glucose management. While there may be some benefits, health effects will vary depending on individual circumstances and how the diet is followed.

Due to its restrictive nature, many people find it hard to follow the keto diet long-term. Additionally, depending on how it is implemented, it can be high in red meat and highly processed, high-fat, and high-sodium foods known to be less healthy.

While some studies have shown beneficial effects on some aspects of health in the short- and mid-term, not much is known about the long-term effects of a keto diet, and weight regain is a concern when stopping. It is also important to note that “yo-yo dieting” (rapid weight loss fluctuations) is associated with an increase in mortality.

If you are thinking about following the keto diet, be sure to discuss it with a healthcare professional first. This is especially important for the following people:

• Individuals with kidney problems, liver issues, and gallbladder problems should consult their healthcare provider before proceeding with a keto diet.
• People who are pregnant or lactating should generally avoid the keto diet due to potential risks and complications.
• People with diabetes who are using insulin, taking medication that lowers blood glucose, or are at risk of ketoacidosis should proceed with caution and be supervised by a healthcare professional.

What to Ask Your Provider Before Starting

As with any change in lifestyle habits, it’s important to talk with a healthcare provider before starting the keto diet. Discuss potential benefits, risks, and suitability for you individually, including any pre-existing conditions, potential side effects, and adjustments to your current medications or supplements.

Below are some questions to consider asking before beginning the keto diet:

• Do I have any health conditions that would make the keto diet unsafe or inadvisable? 
• Will the keto diet help manage my specific health condition(s)? 
• What are the potential risks of the keto diet for me? 
• Is the keto diet a good fit for my overall lifestyle and health goals? 
• What are some alternatives to the keto diet for achieving my health goals?
• What are the common side effects of the keto diet, and how can I manage them? 
• Should I expect any changes in my medications, supplements, or dosages while on the keto diet?
• How long should I stay on the keto diet?
• How can I transition off the keto diet safely and effectively? 
• What are some safe and effective ways to exercise while following the keto diet?

Summary

The ketogenic (keto) diet is very low in carbohydrates, high in fat, and moderate in protein. It is often used to treat medical conditions such as epilepsy and other health concerns, including weight loss and blood glucose control. Talk with a healthcare provider before starting the keto diet.

High-fat foods are encouraged freely in the diet, with protein foods encouraged in moderation. Avoid foods high in carbohydrates, such as grains, legumes, and most fruits.

Due to the restrictive nature of the keto diet, some people find it challenging to follow long-term, and many regain weight after re-introducing carbohydrates. Whether the keto diet can be considered heart-healthy or not remains controversial.