Polyunsaturated Fat: Good or Bad?

03/11/2022 | 5 min. read

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Do you pay attention to how much fat you’re consuming? If so, do you know the percentage of fat that comes from unsaturated fats versus unsaturated fats? Focusing on the types of fat you’re getting in your diet is crucial for people committed to a healthy lifestyle.

To help you better understand what fats are “good” and which are “bad,” the healthcare experts at Healthy Directions offer up a primer on the benefits of polyunsaturated fat. They’ll also discuss how you can increase your intake of good fats.

When you put that knowledge into action, you can potentially reduce your risks of certain health conditions and feel better overall.

What Is Dietary Fat and Does The Body Need It?

No matter the subcategory they fall into, dietary fats are an essential nutrient for the human body. Although dieticians recommend that they be consumed only in small quantities, fat is yet another way to provide the body with the energy it needs to support the health and renewal of the body from a cellular level. The body needs at least some fat to help protect the organs and act as insulation from the cold.

Without fat, the body couldn’t absorb vitamin A, D, E, and K — the fat-soluble vitamins — or produce certain hormones like estrogen, progesterone, and testosterone. Although it often gets a bad rap, dietary fat is vital to the body’s health and functioning.

What Are The Types of Dietary Fats?

When it comes to dietary fat, there are four main categories — saturated fats, monounsaturated fats, polyunsaturated fats, and trans fats.

Each of the four types of dietary fats has its own specific chemical structures and physical properties. Each fat has a carbon chain with added hydrogen atoms; how they’re arranged decides their properties and what type of fat they are.

Saturated fats have carbon atoms bonded together by a single bond with no room between them, which is why they are known as “saturated.” Unsaturated fats have at least one set of carbon atoms bonded by a double bond, and they don’t have the maximum hydrogen atoms. Monounsaturated fats have one of these bonds, and polyunsaturated fats have at least two.

Which Fats Are Good or Bad?

When it comes to “good” and “bad” fats, an easy way to tell without even needing to look it up is to note what it is like at room temperature.

The fats that are generally considered to be “bad”, which are saturated fats and trans fats, stay reasonably solid. An example of this is a stick of butter. While it may get softer if it sits out on the counter all day, it only turns liquid when purposefully heated up. These fats are also most frequently found in animal-based products, although a few (like coconut oil and palm oil) are plant-based and may have some health benefits.

Commonly referred to “Good” fats, on the other hand, are usually liquid even at room temperature. Monounsaturated fats and polyunsaturated fats, like vegetable oil, stay in their liquid state despite most temperature variances. They are predominantly plant-based, coming from nuts, seeds, and vegetables.

But what makes them good or bad comes down to their impact on the body, and it’s just not as simple as saturated=bad and unsaturated=good.

Are Polyunsaturated Fats Good For You?

So, while they fall into the “good” unsaturated fat category, are polyunsaturated fats really good for you?

The answer to that question is yes, in most cases and when eaten in moderation.

Most crucially, polyunsaturated fats can help lower blood cholesterol levels as a whole, specifically LDL cholesterol and triglycerides. Lower LDL cholesterol can work to improve your brain function and decrease your risk of stroke.

Even though they have the same amount of calories as the other categories of fats, polyunsaturated fats provide far more bang for their buck and can even support healthy cell growth. The other types of fats, especially saturated fats, only increase blood cholesterol levels and those associated risks.

In addition, polyunsaturated fats can increase your HDL (or high-density lipoprotein). HDL cholesterol is considered “good” cholesterol to have in your body because it helps to remove some of the other more dangerous forms of cholesterol from your bloodstream.

Because of this, the dietary guidelines most nutritionists recommend are that 20 - 35% of the total calories in the diet come from healthy fats like polyunsaturated fats.

For comparison, no more than 10% should come from saturated fat intake. Eating more than that can lead to high cholesterol, increased cardiovascular disease risks, and even weight gain.

How Can I Get More Polyunsaturated Fats In My Diet?

There are many different sources of polyunsaturated fat to incorporate into the diet, primarily from plant-based sources. That means even strict vegans can find ways to consume more healthy polyunsaturated fats without crossing their morals.

Sunflower seeds, peanuts, pine nuts, and walnuts are great examples of healthy, easy-to-eat polyunsaturated fat. They also contain one of the most essential types of fats — omega-3 fatty acids, and can easily be incorporated into salads or snacks.

Omega-3 fatty acids are an integral component of cell membranes, help regulate genetic function, and may help support heart health.

Unfortunately, the body can’t make them on its own, so making sure you’re getting enough is up to you. Omega-3 supplements or fish oil supplements are also an option if you’re not sure your diet is complete enough, as is increasing your intake of fatty fish like salmon, mackerel, and sardines.

But be cautious about trying to add more polyunsaturated fats into your diet by using vegetable oils in place of butter or shortening. Vegetable oils like soybean oil, canola oil, and safflower oil contain omega-6 fatty acids, another type of polyunsaturated fat, but getting too many omega-6s and not enough omega-3s can lead to poor health.

To Summarize

Although fats are often written off as being strictly “bad” for you, certain types like polyunsaturated fats can benefit the body.

Instead of increasing cholesterol levels and the heart risks, polyunsaturated fats–especially omega-3s–can lower those risks. This type of fat can also increase the amount of good cholesterol, or HDL, in the blood.


Types of Fat | The Nutrition Source | Harvard T.H. Chan School of Public Health

Fat-Soluble Vitamins - Diet and Health | NCBI Bookshelf (

Polyunsaturated Fat | American Heart Association

Healthy Directions Staff Editor