What is the best type of fat to eat and why? A Comprehensive Guide to Healthy Fats

January 7, 2026 •

4 min read

According to the American Heart Association, replacing saturated fat with unsaturated fat can significantly reduce the risk of heart disease. Choosing the right types of fat is a crucial step toward achieving better overall health, from improving heart function to boosting brain performance.

Quick Summary

This guide explains the different types of dietary fats, identifying the healthiest options and their specific health benefits. It covers everything from omega fatty acids to practical food sources.

Key Points

Unsaturated is Best: Prioritize monounsaturated and polyunsaturated fats, found in foods like olive oil, nuts, and fish, to improve cholesterol levels and heart health.
Essential Omega-3s: Include omega-3 fatty acids from sources like fatty fish, walnuts, and flaxseeds, as the body cannot produce them. They are crucial for brain function and reducing inflammation.
Avoid Trans Fats: Eliminate artificial trans fats, which are found in many processed and fried foods, as they are harmful to cardiovascular health.
Limit Saturated Fats: While not as detrimental as trans fats, it's still best to limit your intake of saturated fats from red meat and full-fat dairy, replacing them with healthier unsaturated options.
Cook Smart: Use healthy oils like extra virgin olive oil or canola oil for cooking instead of butter or shortening to make better fat choices.
Read Labels: Check food labels for total fat, saturated fat, and trans fat content to make informed decisions about packaged foods.
Balanced Approach: Instead of focusing on single nutrients, concentrate on a balanced dietary pattern rich in whole, fresh foods that contain a mix of healthy fats.

The Fat Spectrum: Understanding Different Types

Fat is a vital macronutrient essential for energy, absorbing fat-soluble vitamins (A, D, E, K), and supporting cell function. However, not all fats are created equal. The key to a healthy diet is distinguishing between the beneficial and detrimental types and prioritizing the former.

The Good: Unsaturated Fats

Unsaturated fats are widely regarded as the healthiest fats and are liquid at room temperature. They come in two main forms:

Monounsaturated Fats (MUFAs): Known for their protective effect on the heart, MUFAs help lower 'bad' LDL cholesterol levels while maintaining 'good' HDL cholesterol.
Polyunsaturated Fats (PUFAs): These are essential fats that the body cannot produce on its own. PUFAs also lower 'bad' LDL cholesterol and include the vital omega-3 and omega-6 fatty acids.

Sources of healthy unsaturated fats include:

Avocados: Rich in MUFAs and an excellent source of fiber and potassium.
Nuts and Seeds: Almonds, walnuts, chia seeds, and flaxseeds are packed with healthy fats, fiber, and protein. Walnuts are particularly high in omega-3s.
Olive Oil: A staple of the Mediterranean diet, extra virgin olive oil is rich in MUFAs and antioxidants.
Fatty Fish: Salmon, mackerel, sardines, and trout are excellent sources of omega-3 fatty acids EPA and DHA, vital for brain and heart health.

The Bad: Saturated and Trans Fats

While once thought to be completely harmful, the role of saturated fat is now a bit more complex, though health experts still recommend limiting intake. Trans fats, however, remain unequivocally bad for health.

Saturated Fats: These are typically solid at room temperature and are found primarily in animal products like fatty cuts of meat, butter, and full-fat dairy, as well as some tropical oils like coconut and palm oil. Excessive intake can raise LDL cholesterol.
Trans Fats: The most harmful type of fat. Artificial trans fats, created through hydrogenation, both raise bad LDL cholesterol and lower good HDL cholesterol. They are found in many processed foods, fried foods, and certain margarines. The FDA has taken steps to remove artificial trans fats from the food supply.

The Power of Omega-3s

As a crucial type of polyunsaturated fat, omega-3 fatty acids deserve special mention. The body cannot produce these essential fats, which are vital for a wide range of functions. Omega-3s include ALA (plant-based), EPA, and DHA (found in fish and algae).

Key benefits of omega-3s include:

Heart Health: Lowering triglycerides, reducing blood pressure, and preventing irregular heartbeats.
Brain Function: DHA is a major structural component of the brain and eyes, supporting cognitive function and potentially reducing the risk of cognitive decline.
Reduced Inflammation: Chronic inflammation is a driver of many diseases, and omega-3s have potent anti-inflammatory effects.
Mental Health: Studies have linked adequate omega-3 intake to a reduced risk of depression and anxiety.

How to Incorporate Healthy Fats

Incorporating healthier fats into your diet is easier than you might think. Here are some practical tips:

Cook with healthy oils: Swap butter, lard, or shortening for olive, canola, or sunflower oil. For higher heat cooking, oils like avocado oil or refined olive oil are better choices.
Choose fatty fish: Aim to eat fatty fish like salmon, sardines, or mackerel at least twice a week.
Add nuts and seeds: Sprinkle walnuts, flaxseeds, or chia seeds on salads, oatmeal, or yogurt.
Snack smart: Replace processed snacks with a handful of raw, unsalted nuts or seeds.
Use avocado: Add avocado slices to sandwiches, salads, or make homemade guacamole.
Create healthy dressings: Make your own salad dressing using olive oil and a squeeze of lemon juice.

Fat Comparison Table


Fat Type	Primary Sources	Key Health Impact	State at Room Temp
Monounsaturated	Olive oil, avocados, nuts, seeds	Lowers bad LDL cholesterol, raises good HDL	Liquid
Polyunsaturated	Fatty fish, flaxseeds, walnuts, sunflower oil	Lowers bad LDL cholesterol, provides essential omega-3 and omega-6	Liquid
Saturated	Red meat, butter, cheese, coconut oil	Can raise bad LDL cholesterol in excess	Solid
Trans (Artificial)	Fried foods, some processed snacks, margarine	Raises bad LDL cholesterol and lowers good HDL	Solid

Conclusion: Making the Right Choices

For long-term health, the consensus is clear: prioritize unsaturated fats over saturated and completely eliminate artificial trans fats. While all fats contain the same amount of calories per gram, their impact on the body's health is drastically different. By replacing unhealthy fats with heart- and brain-healthy options from whole foods, you can manage your cholesterol, reduce inflammation, and support overall well-being. Focusing on your overall dietary pattern, as emphasized by institutions like Harvard, rather than any single nutrient, is the most effective approach. Choose whole, minimally processed foods that are rich in unsaturated fats, and you will be well on your way to a healthier diet. For more information on understanding dietary fats, visit the Harvard T.H. Chan School of Public Health's nutrition source page on the topic.

Frequently Asked Questions

Monounsaturated fats have one double bond in their chemical structure and are found in olive oil, avocados, and nuts. Polyunsaturated fats have two or more double bonds and include the essential omega-3 and omega-6 fatty acids found in fatty fish, walnuts, and seeds.

While excessive saturated fat intake is linked to higher LDL cholesterol, some recent research has questioned its overall impact compared to replacing it with refined carbs. However, most health experts still recommend limiting saturated fat intake and prioritizing unsaturated fats.

Coconut oil is high in saturated fat, primarily medium-chain triglycerides (MCTs). While some studies suggest MCTs are metabolized differently, a comprehensive analysis found that coconut oil raises LDL ('bad') cholesterol more than vegetable oils. It's generally best to stick with vegetable oils for proven heart-health benefits.

For those who don't eat fish, good plant-based sources of the omega-3 ALA include flaxseeds, chia seeds, and walnuts. It's also possible to take supplements derived from algae to get the beneficial EPA and DHA forms.

Not necessarily. All types of fat are high in calories, so moderation is key. The overall balance of calories consumed versus calories expended determines weight change, and replacing unhealthy fats with healthy ones can help with satiety, potentially aiding weight management.

Oils with a higher smoke point are better for high-heat cooking. Avocado oil is a great choice, as is refined olive oil. Unrefined oils like extra virgin olive oil are better for lower heat cooking or dressings.

For most people, dietary cholesterol (like that found in eggs) has a minimal impact on blood cholesterol levels. A healthy, balanced diet is more important. However, individuals with specific conditions like familial hypercholesterolemia should consult a doctor.