What fat should I be eating on keto? A guide to making healthy choices

On a ketogenic diet, fat typically comprises 70–80% of daily calories, making it your body's primary fuel source. Given this high intake, understanding exactly what fat should I be eating on keto is crucial for both staying in ketosis and promoting overall health.

Quick Summary

To succeed on a keto diet, prioritize healthy unsaturated and saturated fats from sources like avocados, nuts, and fatty fish, while limiting processed vegetable oils and trans fats from your diet.

Key Points

• Prioritize Unsaturated Fats: Focus on sources like avocados, olive oil, nuts, seeds, and fatty fish for heart health and anti-inflammatory omega-3s.

• Include Quality Saturated Fats: Add unprocessed saturated fats from sources like MCT oil, coconut oil, grass-fed butter, and full-fat dairy, but emphasize quality over quantity.

• Avoid Unhealthy Processed Fats: Strictly limit or avoid trans fats found in processed and fried foods, as well as inflammatory omega-6-heavy vegetable oils.

• MCT Oil Can Boost Ketones: MCT oil is quickly converted to ketones, providing a rapid energy source and potentially aiding the transition into ketosis.

• Diversify Your Fat Sources: Mix different healthy fats into meals—like nuts on a salad or avocado in a smoothie—to get a wider range of nutrients.

• Choose Unprocessed Sources: Opt for whole foods like grass-fed meats and pastured eggs over processed counterparts to maximize nutritional benefits.

The Role of Fat in a Ketogenic Diet

The ketogenic diet flips the typical macronutrient ratio, drastically reducing carbohydrates and increasing fat intake to trigger a metabolic state called ketosis. In ketosis, your body switches from burning glucose for energy to burning fat and producing ketones as a fuel source. This means that fat becomes the cornerstone of your diet, providing the energy your body and brain need to function. Because fat makes up such a large portion of your daily calories, the quality of the fats you consume is paramount for long-term health, satiety, and energy levels. Not all fats are created equal, and choosing the right ones is key to maximizing the health benefits of keto.

Healthy Fat Choices: Your Keto Foundation

Focusing on high-quality, unprocessed fat sources is the best approach for a healthy ketogenic diet. These sources provide not only energy but also essential nutrients like fat-soluble vitamins (A, D, E, K) and anti-inflammatory omega-3s.

Prioritizing Unsaturated Fats

Unsaturated fats, which include monounsaturated and polyunsaturated fats, are widely known for their heart-healthy properties and should be a staple in your keto eating plan.

• Avocados and Avocado Oil: Rich in monounsaturated fat and fiber, avocados are a cornerstone of a healthy keto diet. Avocado oil is also a great option for high-heat cooking due to its stability.
• Oily Fish: Salmon, mackerel, sardines, and other fatty fish are excellent sources of omega-3 fatty acids, which have potent anti-inflammatory effects and support heart and brain health.
• Nuts and Seeds: Almonds, macadamia nuts, pecans, walnuts, chia seeds, and flaxseeds provide a mix of healthy unsaturated fats, fiber, and protein. Choose unprocessed versions and watch portion sizes due to their caloric density.
• Olive Oil: Extra virgin olive oil is a foundational healthy fat in many diets, rich in monounsaturated fats and antioxidants. Use it for dressings or finishing dishes rather than high-heat cooking.

Including Quality Saturated Fats

While unsaturated fats are highly recommended, certain saturated fats can also be part of a healthy keto diet, especially when sourced from quality, unprocessed foods.

• MCT Oil and Coconut Oil: Medium-chain triglycerides (MCTs), found in high concentrations in coconut oil, are quickly converted into ketones by the liver, providing rapid energy and potentially easing the transition into ketosis. MCT oil is a concentrated supplement, while coconut oil is a whole-food source.
• Grass-fed Butter and Ghee: Butter from grass-fed cows contains a more favorable fatty acid profile than conventional butter and is a natural source of vitamins A, D, and K. Ghee (clarified butter) is another excellent option with a higher smoke point.
• Full-fat Dairy: Unprocessed, full-fat cheeses are a good source of fat and protein. Grass-fed dairy products are preferable for their omega-3 content.
• Eggs: Pastured or omega-3-enriched eggs are incredibly nutritious, with the fat and nutrients concentrated in the yolk.
• Grass-fed Meats: Fatty cuts of grass-fed beef and other pastured meats contain more omega-3s than grain-fed varieties and can provide a good source of fat and protein.

Fats to Limit or Avoid for a Healthier Keto Diet

Just as important as choosing the right fats is avoiding the unhealthy ones. Certain fats can increase inflammation and undermine your health goals, even on a keto diet.

• Processed and Fried Foods: These often contain trans fats, which are linked to heart disease and inflammation, and should be avoided entirely. This includes margarines, baked goods, and fast food.
• Refined Vegetable and Seed Oils: High in inflammatory omega-6 fatty acids, oils like corn, soybean, and sunflower oil can throw off your omega-3 to omega-6 balance. While some are technically allowed on keto, healthier fats are a better choice.
• Processed Meats: Pre-packaged deli meats, hot dogs, and sausages are often laden with additives and preservatives. While they fit the macronutrient profile, focusing on whole, fresh cuts of meat is a healthier approach.

Healthy Keto Fats vs. Unhealthy Fats: A Quick Comparison

Feature	Healthy Fats (Best for Keto)	Unhealthy Fats (Avoid or Limit)
Sourcing	Whole, unprocessed foods like avocado, olives, nuts, seeds, and grass-fed animals.	Highly processed sources like margarine, processed snacks, and refined vegetable oils.
Fatty Acid Profile	Rich in monounsaturated and polyunsaturated fats (especially omega-3s). Includes quality saturated fats like MCTs.	High in trans fats and potentially inflammatory omega-6s.
Nutrient Density	High in essential vitamins, minerals, and antioxidants.	Often low in nutrients, providing mostly empty calories.
Metabolic Effects	Support ketosis, provide stable energy, and may improve heart health.	Can increase inflammation and raise 'bad' LDL cholesterol.
Culinary Uses	Cold-pressed oils for dressings, stable oils for cooking (avocado oil, ghee), rich flavors in whole foods.	Unstable for high-heat cooking, often used in fried foods and packaged goods.

Practical Tips for Boosting Your Healthy Fat Intake

Incorporating healthy fats into your meals doesn't have to be complicated. Here are some simple strategies:

• Create High-Fat Dressings and Dips: Use extra virgin olive oil or avocado oil as a base for homemade dressings. Guacamole is an excellent high-fat dip for low-carb vegetables.
• Embrace 'Fat Bombs': These are bite-sized snacks made from high-fat ingredients like coconut oil, nut butters, and cream cheese, perfect for curbing cravings.
• Add Fats to Beverages: A popular method is 'bulletproof coffee'—blending coffee with grass-fed butter and MCT oil for a morning energy boost. You can also add heavy cream to coffee or tea.
• Cook with Healthy Oils: Roast vegetables in avocado oil or use grass-fed butter to sauté your protein sources.
• Include Fatty Toppings: Sprinkle nuts, seeds, or shredded cheese over salads and vegetables to increase their fat content.

Conclusion: Making Smart Fat Choices on Keto

While the sheer quantity of fat is a key component of the ketogenic diet, the quality of that fat is what truly dictates the diet's impact on your health. By focusing on a diverse range of healthy fats—prioritizing unsaturated fats and consciously including quality saturated fats—you can ensure your body is receiving optimal fuel and vital nutrients. Limiting or avoiding trans fats, refined vegetable oils, and processed meats is equally important for a successful and health-conscious keto lifestyle. Ultimately, being selective about the fats you consume is the smartest way to support your body while in ketosis.

Frequently Asked Questions

What is the ideal fat percentage on a ketogenic diet?

While the ideal percentage can vary by individual, a standard ketogenic diet typically consists of approximately 70–80% of total daily calories from fat.

Is MCT oil necessary for the keto diet?

MCT oil is not strictly necessary but can be a beneficial supplement. It provides a quick source of energy and helps increase ketone production, which can aid in achieving and maintaining ketosis.

Can I eat butter and red meat on keto?

Yes, butter and red meat can be part of a keto diet. For optimal health, choose grass-fed butter and fattier cuts of grass-fed red meat, as they offer a better fatty acid profile.

What happens if I don't eat enough fat on keto?

Not eating enough fat can prevent your body from entering or sustaining ketosis, leading to fatigue, reduced physical performance, and increased hunger.

How much saturated fat is too much on keto?

While saturated fat is consumed on keto, it's best to prioritize unsaturated fats. Consuming excessive amounts of saturated fat, especially from unhealthy sources, can increase 'bad' LDL cholesterol.

Which fats should I avoid entirely on keto?

You should avoid all trans fats, often listed as 'partially hydrogenated oils,' found in processed snacks and fried foods. It is also recommended to limit refined vegetable oils like corn and soybean oil due to their high omega-6 content.

What is the best type of oil for cooking on keto?

The best oils for high-heat cooking on keto are those with a high smoke point, such as avocado oil and ghee. Extra virgin olive oil is better suited for lower heat or finishing dishes.