What are sources of fat?

December 25, 2025 •

3 min read

Fats are a vital macronutrient, providing over twice the energy per gram compared to carbohydrates or protein. A balanced diet requires various fats, and the type and source are more important than the total amount, influencing heart health and well-being.

Quick Summary

Learn about the primary fat types: saturated, unsaturated, and trans fats, with food source examples. This guide highlights which fats to choose for a healthier diet and which to limit.

Key Points

Saturated Fat Sources: Found in animal products like red meat and full-fat dairy, as well as tropical oils such as coconut and palm oil, and should be limited.
Heart-Healthy Unsaturated Fats: Monounsaturated fats (avocados, olive oil) and polyunsaturated fats (fatty fish, nuts, seeds) are liquid at room temperature and beneficial for heart health.
Essential Fatty Acids: Omega-3 and Omega-6 are polyunsaturated fats that the body cannot produce and must be obtained from dietary sources like fatty fish, flaxseeds, and walnuts.
Harmful Trans Fats: Primarily a byproduct of industrial processing (partial hydrogenation), found in many baked and fried processed foods, and should be avoided entirely.
Smart Food Swaps: Replace foods high in saturated and trans fats with sources of healthy fats like nuts for snacks, olive oil for cooking, and fatty fish for meals.
Fat is Energy-Dense: All types of fat provide more than double the calories per gram compared to protein or carbohydrates, emphasizing the importance of moderation alongside healthy choices.

Understanding the Main Types of Fat

Fats are classified based on their chemical structure, impacting their effects on the body. The primary types of dietary fat are saturated, unsaturated (monounsaturated and polyunsaturated), and trans fats. Choosing the correct fats and reducing unhealthy ones supports a healthier lifestyle.

Saturated Fat: Animal Products and Tropical Oils

Saturated fats are typically solid at room temperature and come from animal products and some plant-based oils. High saturated fat intake can raise LDL cholesterol, increasing heart disease risk. Limiting saturated fat is recommended by many nutrition experts.

Common sources of saturated fat include:

Fatty meats: Beef, lamb, pork, and processed meats like sausages and bacon.
Full-fat dairy: Butter, cheese, cream, and ice cream.
Tropical oils: Coconut oil, palm oil, and palm kernel oil.
Baked goods and snacks: Commercial biscuits, cakes, pastries, and some savory snacks.

Unsaturated Fat: The Heart-Healthy Choices

Unsaturated fats are liquid at room temperature and generally considered 'good' or 'heart-healthy' fats. They can lower bad LDL cholesterol and provide essential fatty acids that the body cannot produce. There are two main types of unsaturated fats:

Monounsaturated Fat

This fat helps maintain good HDL cholesterol levels while reducing LDL cholesterol. It is widely found in plant-based sources and is a key component of the Mediterranean diet.

Sources of monounsaturated fat:

Avocados
Nuts: Almonds, pecans, hazelnuts, and peanuts
Oils: Olive, canola, peanut, and safflower oil
Seeds: Sesame seeds

Polyunsaturated Fat (Omega-3 and Omega-6)

Polyunsaturated fats are essential fatty acids, meaning the body needs them but cannot produce them. There are two main types: Omega-3 and Omega-6 fatty acids.

Sources of Omega-3:

Fatty fish: Salmon, mackerel, herring, sardines, and trout.
Plant-based sources: Flaxseed, walnuts, and chia seeds.

Sources of Omega-6:

Vegetable oils: Sunflower, corn, and soybean oil.
Nuts and seeds: Walnuts and pumpkin seeds.

Trans Fat: The Harmful Industrial Fat

Trans fats are the most harmful dietary fat, with no known health benefits. They raise bad LDL cholesterol and lower good HDL cholesterol, creating inflammation and significantly increasing heart disease risk. While small amounts occur naturally in some animal products, the primary concern is industrially produced trans fats through partial hydrogenation. The World Health Organization estimates that industrially produced trans fat causes over 278,000 deaths annually. Many countries have banned or restricted their use.

Sources of trans fat to avoid include:

Processed baked goods: Cakes, cookies, and crackers made with partially hydrogenated oils.
Fried foods: French fries, doughnuts, and fried chicken from fast food chains.
Stick margarine and vegetable shortening.
Packaged snacks: Microwave popcorn and some pre-packaged snacks.

Making Healthier Fat Choices

Making healthier choices involves being a mindful consumer and understanding food labels. Swapping butter for olive or canola oil in cooking can make a significant difference. Opting for lean meat and reduced-fat dairy products decreases saturated fat intake. Including more whole foods like nuts, seeds, and avocados in your diet increases beneficial unsaturated fats. The key is prioritizing whole food sources of healthy fats over processed items with harmful trans fats.

Comparison of Fat Sources


Fat Type	Common Sources	State at Room Temperature	Health Impact	Sources
Saturated Fat	Fatty meat, full-fat dairy, coconut oil, palm oil	Solid	Increases 'bad' LDL cholesterol; risk factor for heart disease
Monounsaturated Fat	Olive oil, avocados, almonds, peanuts	Liquid	Can lower 'bad' LDL cholesterol and raise 'good' HDL
Polyunsaturated Fat	Fatty fish (salmon), flaxseed, walnuts, sunflower oil	Liquid	Includes essential Omega-3 and Omega-6 fatty acids
Trans Fat	Processed foods, fried foods, stick margarine	Solid	Raises 'bad' LDL, lowers 'good' HDL; creates inflammation and increases heart disease risk

Conclusion

Fats are a crucial part of a healthy diet, essential for energy storage, vitamin absorption, and cell function. However, distinguishing between healthy and unhealthy sources is vital for long-term health. Saturated fats should be limited, and industrial trans fats should be avoided, while incorporating healthy unsaturated fats from plant and fish sources offers significant benefits for cardiovascular health and well-being. Prioritizing whole, unprocessed foods is the most effective strategy for the right balance of dietary fats. To learn more about the best fats for you, see this comprehensive guide from Harvard Health: The truth about fats: the good, the bad, and the in-between.

Frequently Asked Questions

Saturated fats are typically solid at room temperature and come primarily from animal sources and tropical oils, while unsaturated fats are liquid at room temperature and mainly come from plant-based foods and fish. Unsaturated fats are generally considered healthier for heart health.

Excellent sources of monounsaturated fat include avocados, olive oil, canola oil, peanuts, and other nuts like almonds and pecans. These fats can help lower bad LDL cholesterol levels.

Trans fats are considered the worst type of fat because they not only raise bad LDL cholesterol but also lower good HDL cholesterol. This double-negative effect increases the risk of heart disease and stroke more than any other fat type.

To identify trans fats in packaged foods, check the ingredients list for terms like 'partially hydrogenated oil' or 'hydrogenated vegetable oil'. While some labels may claim 0g of trans fat, they can contain up to 0.5 grams per serving.

The best sources of Omega-3s are fatty fish like salmon, mackerel, herring, and sardines. Plant-based sources include flaxseed, walnuts, and chia seeds.

Despite some marketing claims, coconut oil and palm oil are high in saturated fat and therefore should be consumed sparingly. Most health organizations recommend using healthier oils like olive or canola oil for daily cooking.

While many plant-based fats, such as those from avocados, nuts, and seeds, are healthy, some plant-based oils like coconut and palm oil are high in saturated fat. It is important to distinguish between the types of fat, as some are healthier than others, regardless of their plant or animal origin.