What Are the Best Foods to Eat and Not Eat on a Ketogeneic (Keto) Diet?

Medically Reviewed on 5/19/2022

How does a ketogenic diet work?

A ketogenic diet is a high-fat, low-carb diet that causes your body to rely on ketone bodies for energy. The best foods to eat on a ketogenic diet are meats and non-starchy vegetables and the worst foods to eat are high-fat meats and ketogenic snack foods.
A ketogenic diet is a high-fat, low-carb diet that causes your body to rely on ketone bodies for energy. The best foods to eat on a ketogenic diet are meats and non-starchy vegetables and the worst foods to eat are high-fat meats and ketogenic snack foods.

A ketogenic diet, commonly called a keto diet, first started as a 1920's treatment for epilepsy. It has become wildly popular in the last few years among celebrities, athletes, and the general public,  A keto diet is a high fat, moderate protein, low-carb diet, with 60 to 80% of all calories coming from fat. Keto dieters often credit the diet for weight loss, increased energy, and reduced cravings, but critics wonder if the high-fat diet is safe. If you're considering going keto, read on to learn what you need to know about a ketogenic diet.

A ketogenic diet is a high-fat, low-carb diet that causes your body to rely on ketone bodies for energy. Ketone bodies are a fuel that your liver produces from stored fat. While most cells in the body prefer to use glucose for fuel, if you're severely limiting your intake of carbohydrates, your body will become fat adapted and enter a state called ketosis where most of your cells are using ketone bodies for energy. 

There's some evidence that a ketogenic diet works better than low-fat diets for weight loss. However, research is still needed to determine how safe and effective this type of diet is in the long term.

Ketogenic diets are drastically different than standard American diets, which often have a carbohydrate content of 50% or more. Most people aim to keep carbohydrate intake lower than 20 to 50 grams a day on keto, which some people find difficult to maintain. For example, a single medium apple contains around 25 grams of carbohydrates. Some low-carb diets, such as paleo or primal diets, follow a similar high-fat, low-carb approach but allow for more flexibility with carbohydrate intake. 

What are the best foods to eat on a ketogenic diet?

Many critics of keto diets note that adherents can over-rely on highly processed foods high in fat, such as processed meats and cheeses. Dirty keto, slang for a keto diet that doesn't consider food quality, may have additional health risks as foods like double cheeseburgers (minus the bun) and pork rinds can be consumed freely. 

The best foods to eat on a ketogenic diet are high-nutrient, low-carb, single-ingredient foods. A healthy keto diet includes plenty of low-carb vegetables for micronutrients and a variety of quality fat sources. 

Good food choices on a keto diet include:

  • Leafy greens such as kale, chard, arugula, bok choy, and spinach
  • Cruciferous vegetables like broccoli, cauliflower, and Brussels sprouts 
  • Non-starchy nightshades such as tomatoes, eggplant, and bell peppers
  • Mushrooms
  • Eggs
  • Avocados and avocado oil
  • Nuts and seeds such as macadamia nuts, flax seeds, and chia seeds
  • Olives and cold-pressed extra virgin olive oil
  • Coconuts and coconut oil
  • Full fat, unsweetened Greek yogurt
  • Fatty fish like salmon, tuna, or sardines
  • Grass-fed beef
  • Small amounts of low carb fruits, like berries

What foods should be avoided on a ketogenic diet?

Most people know to avoid high-carb processed foods like bread, cake, and bagels on a ketogenic diet. Still, high-carb foods that are usually considered healthy are also limited or completely avoided, like bananas, mangoes, grapes, sweet potatoes, and pineapple. 

Many high-fat foods are technically keto but aren't the best choice for promoting overall health. These include foods such as:

Processed high-fat meats like bacon, sausage, hot dogs, pepperoni, beef jerky, and deli meat. 

Processed meats have been linked to chronic diseases such as diabetes, heart disease, and some forms of cancer, as well as the overall risk of mortality. 

Processed meats often have a very high salt content and contain chemical preservatives like nitrates.

Packaged keto snack foods like keto cookies, cereal, or cheese puffs. 

As keto has gained more popularity, more keto and low-carb snack foods have been produced. These snacks have been designed to imitate common foods on a standard American diet. Generally speaking, these products have little nutritional value. Also, they sometimes contain a whole day's worth of carbohydrates for someone following a keto diet. 

When eating keto, it's essential to focus on consuming high-quality vegetables and fruits for your limited carbohydrate intake. Processed snack foods won't provide the micronutrients you need. 

Pork rinds

Pork rinds are often used like a keto version of potato chips, eaten in front of the TV, as a side dish with a burger, etc. While this can be fine in moderation, pork rinds are high in salt and low in nutrients and shouldn't be a staple of a healthy keto diet. 

Processed cheeses, like American cheese or pre-packaged shredded cheese

Processed cheese is high in sodium. Some processed cheeses are even saltier than seawater. While you don't need to give up cheese completely on keto, focus on unprocessed cheeses and use cheese as a condiment rather than the main ingredient. 

While more long-term research is needed, ketogenic diets and other long-term diets can be an option for people struggling with obesity or other chronic health concerns. As with any significant dietary change, you should consult your doctor or a nutritionist before starting a keto diet. Approaching keto from a healthy mindset and focusing on nutrient-dense, whole foods will likely lead to the best results.

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Medically Reviewed on 5/19/2022
References
SOURCES:

British Heart Foundation: "7 cheese facts that will surprise you."

Harvard Health Publishing: "Should you try the keto diet?"

Harvard School of Public Health: "Are all processed meats equally bad for health?"

The Journal of Nutrition: "The Ketogenic Diet: Evidence for Optimism but High-Quality Research Needed."

Mayo Clinic: "Is the keto diet for you? A Mayo expert weighs in."

MD Anderson Cancer Center: "Processed meat and cancer: What you need to know."