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.
How Does Ketosis Feel?
Without testing for ketones, many people wonder if they are really in ketosis. In the early days of ketosis, people often report feeling a group of symptoms of what is commonly called the “keto flu”. These symptoms often mimic the flu, including headaches, fatigue, nausea, and irritability.
In addition to the “keto flu”, there are other signs and symptoms that may indicate a metabolic shift into ketosis. These include:
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 Is Ketoacidosis?
Ketoacidosis, also known as diabetic ketoacidosis (DKA), is a serious and potentially life-threatening medical complication in which the body produces excess amounts of ketones, leading to a build-up in the blood. It is most common among people with type 1 diabetes, though people with type 2 diabetes can also develop DKA.
Symptoms include:
- Excessive thirst
- Frequent urination
- Fruity-smelling breath
- Deep, rapid breathing
- Flushed face
- Dry mouth
- Headache
- Muscle aches
- Fatigue
- Abdominal pain
- Nausea
- Vomiting
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.
The Ketogenic Diet: Principles, Benefits, and Considerations
Understanding the Ketogenic Diet
The ketogenic diet, often referred to as the keto diet, is characterized by a significant reduction in carbohydrate intake and a substantial increase in fat consumption. Initially designed for managing childhood epilepsy, the diet has gained popularity for its potential benefits in weight management and blood sugar regulation.
Core Principles of the Keto Diet
The principal aim of the keto diet is to induce a metabolic state known as ketosis. This occurs when the body, deprived of its preferred energy source—glucose from carbohydrates—shifts towards using ketones, which are produced during fat breakdown in the liver. To achieve ketosis, individuals typically limit their carbohydrate intake to 20-50 grams per day, while consuming moderate amounts of protein and high levels of fats.
On a strict ketogenic diet, the proportion of daily caloric intake is roughly:
- 5-10% from carbohydrates
- 15-30% from protein
- 70-80% from fats
Food Choices on the Keto Diet
Foods to Include
The following foods are encouraged on the keto diet:
- High-fat dairy products (like butter and cream)
- Oils (including olive oil, avocado oil, and coconut oil)
- Fatty cuts of meat (such as beef, pork, and lamb)
- Fish and seafood
- Eggs
- Nuts and seeds (almonds, walnuts, flaxseeds)
- Non-starchy vegetables (leafy greens, broccoli, zucchini)
- Berries in moderation
- Unsweetened beverages (such as coffee and tea)
- Herbs and spices
Foods to Avoid
To maintain ketosis, certain foods must be avoided, including:
- Grains (like wheat, rice, and oats)
- Root vegetables (such as potatoes and sweet potatoes)
- Most fruits (with limited exceptions, like berries)
- Sugary foods and beverages
- Processed foods high in carbohydrates
Potential Benefits of the Keto Diet
1. Weight Loss
The ketogenic diet may lead to faster initial weight loss compared to traditional low-calorie diets. However, long-term weight loss outcomes appear to be similar across different dietary approaches.
2. Blood Sugar Regulation
By significantly lowering carbohydrate intake, the keto diet can stabilize blood glucose levels and improve insulin sensitivity. This can be particularly beneficial for individuals with type 2 diabetes.
3. Impact on Cholesterol and Heart Health
The effects of the keto diet on heart health are still being studied. Some research indicates potential improvements in triglyceride levels and increases in high-density lipoprotein (HDL) cholesterol, though concerns remain regarding low-density lipoprotein (LDL cholesterol) levels.
Considerations Before Starting the Keto Diet
It is crucial to consult a healthcare professional before beginning the ketogenic diet, especially for individuals with underlying health conditions. Important considerations include:
- Pre-existing health issues, such as kidney or liver problems
- Pregnancy or lactation status
- Current medications and potential adjustments needed
Additionally, while some may experience rapid results, adherence to the diet can be challenging, and the long-term impacts are not yet fully understood.
Conclusion
The ketogenic diet presents a distinct approach to nutrition focused on high fat and low carbohydrates. While it offers potential benefits such as weight loss and improved blood sugar control, individual experiences may vary. Anyone considering this diet should do so under medical guidance and consider both its short- and long-term implications for health.
