Unsaturated Fats: The Type of Fat That is Liquid at Room Temperature and Can Improve Cholesterol

December 22, 2025 •

3 min read

According to health organizations like the American Heart Association, replacing saturated and trans fats with unsaturated fats is a key strategy for better heart health. The specific type of fat that is liquid at room temperature and can improve cholesterol is unsaturated fat.

Quick Summary

Unsaturated fats, including both monounsaturated and polyunsaturated varieties, are liquid at room temperature. They are beneficial for heart health and can lower bad cholesterol levels when consumed in place of saturated fats.

Key Points

Unsaturated Fats Are Liquid: This category of fats, which includes monounsaturated and polyunsaturated types, is typically liquid at room temperature.
Improves Cholesterol Profile: Consuming unsaturated fats instead of saturated fats can lower harmful LDL ('bad') cholesterol and maintain beneficial HDL ('good') cholesterol.
Monounsaturated Fat Sources: Found abundantly in olive oil, canola oil, peanut oil, and avocados.
Polyunsaturated Fat Sources: Excellent sources include fatty fish (salmon, mackerel), walnuts, and flaxseeds.
Key to Heart Health: A diet rich in unsaturated fats can reduce the risk of heart disease and stroke.
Essential Fatty Acids: Polyunsaturated fats provide essential omega-3 and omega-6 fatty acids that the body cannot produce on its own.
Focus on Replacement: The benefit comes from replacing saturated fats in your diet with unsaturated ones, rather than simply adding them on top.

What Are Unsaturated Fats?

Unsaturated fats are a category of healthy fats that are distinguished by their chemical structure, which contains at least one double bond in the fatty acid chain. This molecular difference is what makes them liquid at room temperature, unlike saturated fats which are solid. These beneficial fats are primarily found in plant-based foods and fish, offering significant advantages for cardiovascular health. Consuming unsaturated fats in moderation can help lower low-density lipoprotein (LDL), or 'bad' cholesterol, and may even help increase high-density lipoprotein (HDL), or 'good' cholesterol.

There are two main types of unsaturated fats that offer these positive effects: monounsaturated fats (MUFAs) and polyunsaturated fats (PUFAs). Understanding the difference between them can help you make informed dietary choices.

Monounsaturated Fats (MUFAs)

These fats contain one double bond in their chemical structure, which is why they are called 'mono'unsaturated. They are typically liquid at room temperature but may begin to solidify when chilled. Key benefits include lowering LDL cholesterol levels, which reduces the risk of heart disease and stroke, and providing vitamin E, an important antioxidant.

Excellent sources of monounsaturated fats include:

Olive, peanut, and canola oils
Avocados
Nuts such as almonds, hazelnuts, and pecans
Seeds such as pumpkin and sesame

Polyunsaturated Fats (PUFAs)

Polyunsaturated fats contain multiple double bonds in their chemical structure ('poly'). Like MUFAs, they are also liquid at room temperature. PUFAs provide essential fatty acids that the human body cannot produce, such as omega-3 and omega-6. Both are crucial for brain function and cell growth.

Key sources of polyunsaturated fats include:

Oily fish like salmon, mackerel, and trout
Vegetable oils such as sunflower, corn, and soybean oils
Walnuts
Flax seeds
Tofu and soybeans

Unsaturated vs. Saturated Fats: A Key Comparison

Replacing unhealthy saturated and trans fats with healthy unsaturated fats is the most effective strategy for improving cholesterol. Below is a comparison to clarify the main differences between these fat types.


Characteristic	Unsaturated Fats	Saturated Fats
State at Room Temperature	Liquid (oils)	Solid (butter, lard)
Effect on Cholesterol	Improves profile (lowers LDL, may raise HDL)	Raises LDL ('bad') cholesterol
Primary Food Sources	Plant-based oils, nuts, seeds, fatty fish	Animal products (red meat, dairy), some tropical oils (coconut, palm)
Molecular Structure	Contains at least one double carbon bond	All carbon bonds are single
Cardiovascular Health	Reduces risk of heart disease and stroke	Increases risk of heart disease and stroke

How to Incorporate Healthy Fats into Your Diet

Making conscious substitutions is the easiest way to improve your fat intake. Here are some practical tips:

Swap cooking oils: Use olive, canola, or avocado oil instead of butter, lard, or coconut oil. Olive oil and avocado oil are both rich in monounsaturated fats and are excellent for cooking.
Add nuts and seeds: Sprinkle nuts like walnuts and almonds or seeds like flax and chia on salads, yogurt, or oatmeal. A small handful of nuts is a great snack.
Eat more fish: Aim for at least two servings of fatty fish like salmon or mackerel per week to boost your omega-3 intake.
Incorporate avocado: Add avocado slices to sandwiches, salads, or make guacamole for a delicious source of monounsaturated fats.
Read food labels: Be vigilant about ingredients, particularly for processed foods. Look for 'partially hydrogenated oils' which indicate the presence of unhealthy trans fats.

Conclusion

Unsaturated fats—specifically monounsaturated and polyunsaturated fats—are the types of fat that remain liquid at room temperature and have a positive impact on cholesterol levels. By replacing less healthy saturated and trans fats with these heart-healthy options, you can significantly lower your LDL cholesterol and support overall cardiovascular health. Making small, consistent changes to incorporate more avocados, nuts, seeds, plant oils, and fatty fish into your diet is a simple and effective strategy for a healthier heart. For more information on dietary fats and heart health, visit the American Heart Association's official website.

Frequently Asked Questions

The best strategy is to make simple swaps, like using liquid vegetable oils such as olive or canola oil for cooking instead of solid fats like butter, and choosing nuts and seeds as snacks instead of processed, fatty foods.

No, some plant-based oils, most notably coconut and palm oil, are high in saturated fats and are therefore solid at room temperature.

Unsaturated fats improve cholesterol levels by lowering LDL ('bad') cholesterol. Monounsaturated fats can also help maintain or increase HDL ('good') cholesterol levels.

Monounsaturated fats have one double carbon bond, while polyunsaturated fats have more than one. Both are healthy, but polyunsaturated fats contain essential fatty acids that the body cannot produce.

Olive oil, avocado oil, canola oil, and sunflower oil are all excellent choices due to their high unsaturated fat content. Some, like avocado oil, are also good for high-heat cooking.

Just adding healthy fats to a diet already high in saturated fats is not enough. The health benefit comes from the overall reduction of unhealthy fats and the subsequent increase in unsaturated fats.

No, while unsaturated fats are healthy, they are still calorie-dense. It is important to consume all fats, including unsaturated ones, in moderation as part of a balanced diet to manage weight.