Fats have long been a contentious part of the American diet. In the past, fats were labeled as “bad” and to be avoided—leading to the development of many “fat free” products on grocery store shelves.

But any nutritionist will tell you that fats are NOT necessarily a “bad” thing for your diet. It all depends on the type and amount of fat you eat.

Fats are an important part of the diet because they not only provide energy, but they also help your body to absorb certain vitamins and minerals.

If you look at the nutrition labels on foods, you'll see that two different kinds of fats are listed: saturated and unsaturated.

What's the difference?

Saturated fats are solid at room temperature and generally come from animal products such as meat and dairy products (milk, butter, shortening, and cheese).

Unsaturated fats are loosely packed, tend to be liquid at room temperature, and come from plants. There are two main types of unsaturated fats:

Monounsaturated fats come from olive oil, peanut oil, canola oil, avocados, nuts, and seeds.

Polyunsaturated fats come from fatty fish--like sardines, tuna, and salmon--as well as flax and flaxseed oil, canola oil, and walnuts (among other things).

Nutritionists have long argued that you should aim to eat more unsaturated fat than saturated fat.

This is because diets high in saturated fat are often correlated with elevated low-density lipoprotein (LDL) ("bad") cholesterol levels. High LDL cholesterol puts you at more risk of developing heart disease and type 2 diabetes (Yikes!)

Unsaturated fats, on the other hand, can actually improve your cholesterol levels, lowering your risk of developing cardiovascular disease.

HOWEVER--there is one kind of fat that you should try to steer clear of: trans fats.

Trans fats are often found in fried food as well as in processed snacks and baked goods. This type of fat has no nutritional value and is actually harmful for your health because it raises your bad (LDL) cholesterol levels and lower your good (HDL) cholesterol levels (which can lead to heart disease and stroke).

For more info on fats, read the article What’s the Difference Between Saturated and Unsaturated Fat? on Healthline.com.

Jayd Harrison is a personal trainer and content creator. She helps people to build muscle, burn fat, and clean up their diets with her online coaching programs and social media content. Check out some of Jayd’s coaching videos on Youtube, or join Jayd live on Twitch and follow on social media.