Saturated vs. Unsaturated Fats

The main differences between saturated and unsaturated fat is their form at room temperature and their impact on your health.

Saturated fats (including a type called trans fat) tend to stay solid and can cause fatty deposits in blood vessels, leading to atherosclerosis ("hardening of the arteries"). By contrast, unsaturated fats stay liquid at room temperature and are less likely to clog your arteries.

In addition, most unsaturated fats are derived from plant sources (like olive, avocado, and nuts), while most saturated fats come from animal sources (like red meat, poultry, and dairy).

This article takes a look at saturated vs. unsaturated fat, including examples of each and which are more likely to put you at risk of high cholesterol and heart disease. It also explains how to include each in a healthy, balanced diet.

What Is Saturated Fat?

Saturated fats are called "saturated" because of their chemical structure. All fats are made up of carbon, hydrogen, and oxygen molecules. Saturated fats are "saturated" with hydrogen atoms, which means they have the greatest number of hydrogen atoms possible and no double bonds in their chemical structure.

What does this chemical structure mean? For one, it means that, like butter, they become solid at room temperature.

Foods that contain saturated fats include:

• Animal meat including beef, poultry, pork
• Certain plant oils such as palm kernel or coconut oil
• Dairy products including cheese, butter, and milk
• Processed meats including bologna, sausages, hot dogs, and bacon
• Pre-packaged snacks including crackers, chips, cookies, and pastries

Why Limit Saturated Fats in Your Diet

Saturated fat should make up less than 6% of your daily caloric intake, according to AHA recommendations. Limiting your saturated fat intake, especially certain types of saturated fat, could improve your heart health.

Some studies have shown that consuming a high amount of saturated fats may increase your low-density lipoprotein (LDL), also known as "bad" cholesterol. High LDL levels may increase your risk of heart disease. However, there have been multiple studies that say saturated fat does not actually have a negative effect on your heart.

The more saturated fat you eat, the more LDL you seem to have in your body. However, studies have shown that not all LDL is bad. Saturated fat increases the amount of large, buoyant LDL you have. These larger LDL particles do not appear to increase your risk of heart disease.

On the other hand, small, dense LDL has been shown to contribute to atherosclerosis, the build-up of plaque on your arteries, which leads to heart disease. Eating saturated fat doesn't appear to increase your small, dense LDL. In a few cases, the risk of plaque build-up even went down when saturated fat was consumed.

The type of saturated fat-containing foods you eat also seems to make a difference in your heart health. One large study suggested that consuming dairy products may actually lower the risk of cardiovascular disease. At the same time, including processed meats in your diet could increase your risk of cardiovascular disease.

What Is Unsaturated Fat?

Unsaturated fats are typically liquid at room temperature. They differ from saturated fats in that their chemical structure contains one or more double bonds.

They can be further categorized as:

• Monounsaturated fats: This type of unsaturated fat contains only one double bond in its structure. Monounsaturated fats are typically liquid at room temperature and include canola oil and olive oil.
• Polyunsaturated fats: This type of unsaturated fat contains two or more double bonds in its structure. They are also liquid at room temperature. Polyunsaturated fats include safflower oil, sunflower oil, and corn oil.

Incorporating Unsaturated Fats in Your Diet

Monounsaturated and polyunsaturated fats should make up most of your daily fat intake, according to AHA recommendations.

Examples of foods that contain unsaturated fats include:

• Nuts
• Plant oils
• Certain fish like salmon, tuna, and anchovies, which contain omega-3 unsaturated fatty acids
• Olives
• Avocados

Difference Between Fat and Cholesterol

Cholesterol and fats are both lipids. They are found in the food you eat, and they circulate in your bloodstream. Cholesterol has a more complex chemical structure compared to fats.

In the body, cholesterol is bound to protein as low-density lipoprotein (LDL) or high-density lipoprotein (HDL). LDL may increase your risk of heart disease, while HDL, often called "good" cholesterol, is considered to be protective against heart problems.

Which Fats Are Good or Bad in Your Diet?

If you are watching your cholesterol and triglyceride levels (another type of fat that circulates in the blood), try to include a variety of healthy foods like lean meats, vegetables, fruits, legumes, and whole grains.

More research is needed to understand the influence of unsaturated and saturated fats on cardiovascular disease. Although there has been research suggesting that saturated fats are not as bad for heart health as they were once thought, doctors still usually recommend limiting your intake.

A handful of walnuts or a lean piece of beef is a better choice for your meals than a bag of chips or sausage links. Both may contain fats, but the nuts and lean meat also contain vitamins, minerals, and other healthy nutrients.

The chips and processed meat, meanwhile, may be higher in sugar, chemical preservatives, salt, and trans fats. All of these can have a negative effect on your lipid levels and heart health.

Summary

There’s a lot of disagreement about how much saturated fat is “safe” or “healthy.” Some types of saturated fat are associated with heart disease.

Saturated fat found in beef, butter, margarine, and other rich foods may not increase your cardiovascular risk since they result in larger LDL. However, your best bet might be to limit the saturated fats in your diet anyway.

Instead, choose unsaturated fats as your main source of fats and lipids. This will help you to avoid unhealthy sources of saturated fats, such as processed meats, that are known to increase the risk of health problems.

A Word From Verywell

It can be confusing to try and untangle which fats you should consume and which you should avoid, especially as newer research changes what you may have heard before. The best course is to check with your doctor and continue to include foods in your diet that are natural, unprocessed, high in nutrients, and lower in calories.