Fat, along with carbohydrate and protein, constitutes a basic macronutrient component of food. However, not all fats are created equal. Understanding the difference between the various types of fat is key, and there are different types of fat that have various health benefits associated with them. 

As a macronutrient, fat promotes:

  • Energy production

  • Healthy skin and hair

  • Fat-soluble vitamin absorption

  • Body insulation

Saturated and Trans Fat

Saturated fats are those that are usually in a solid form at room temperature:

  • Butter

  • Palm and coconut oils

  • Cheese

  • Red meat[1]

High intake of these types of fat is often associated with heart disease risk and unhealthy weight gain. This is because high consumption of saturated fat raises levels of “bad” cholesterol, called low-density lipoprotein (LDL).

In 2015, the U.S. Food and Drug Administration gave the food industry three years to remove all artificial trans fats from food products, declaring them unsafe.[2] Trans fats are produced as a result of processing liquid oils into solid fats, a process called hydrogenation. Trans fats are found in:

  • Fried and battered food

  • Shortening and stick margarine

  • Cakes, cake mixes, pies, pie crust[3]

Like saturated fats, trans fats raise levels of LDL cholesterol, and they reduce levels of high-density lipoprotein (HDL), also known as “good” cholesterol. Trans fats are associated with increased risk of heart diseases, weight gain, and stroke. 

Unsaturated Fat

Unsaturated fat can be either mono-unsaturated fatty acids (MUFAs) or polyunsaturated fatty acids (PUFAs). Oil sources of unsaturated fat are usually those that are liquid at room temperature:

  • Olive and canola oil 

  • Safflower, sunflower, corn, and soy oil 

MUFAs exist in vegetable oils, nuts, avocadoes, and other plant foods.[4] PUFAs are found in fish, vegetable oils, nuts and seeds, and some other animal and plant foods.[5] Both MUFAs and PUFAs are associated with decreased risk of chronic diseases.[6] Omega-6 and omega-3 fatty acids are two different kinds of PUFAs, each with their own distinct health benefits. Omega-6 fatty acids include linoleic acid (LA) and arachidonic acid. Omega-3 fatty acids include alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).

Read more about omega-3 fatty acids.

References

  1. Facts about saturated fats. MedlinePlus, 2018.
  2. Artificial trans fats banned in U.S. 2018.
  3. Facts about trans fats. MedlinePlus, 2018.
  4. Facts about monounsaturated fats. MedlinePlus, 2018.
  5. Facts about polyunsaturated fats. MedlinePlus, 2018.
  6. Hu, F.B., et al., Dietary fat intake and the risk of coronary heart disease in women. N Engl J Med, 1997. 337(21): p. 1491-9.