Fats: Oiling Your Engine 101

What comes to mind when you hear the word fats? Do you envision bacon sizzling in a greasy pan; smooth, olive oil drizzling onto a bed of greens; or maybe even a sockeye salmon gracefully swimming up the Kenai River? All of these images involve fats of various kinds. Knowing the basic principles of how fats metabolize in the body as well as the kinds of fats humans ingest in their diets is necessary for maintaining health.

Fats, also called lipids, are utilized in many functions within the body from energy production and nutrient absorption to inflammation regulation and cardiovascular health maintenance. There are three main kinds of lipids: unsaturated, saturated, and trans-saturated – each of which carries different health ramifications. Let’s take a closer look at how fats work in the body.

As the second macronutrient we are examining, fat offers the body another principle energy source. When fully metabolized, fat offers 9 calories per gram consumed. While not converted to energy as quickly as carbohydrates, at rest, fats are the body’s primary source of energy, and as the body usually has ample stores of fat, it provides a stable, long-term option. However, this requires training the body to depend less on carbohydrates for fuel and instead utilize fats to a greater degree.¹ This is done by limiting the amount of moderate to high glycemic foods in favor of lower glycemic choices.²

Furthermore, one must be careful of the amount of carbohydrates consumed in one instance so that they do not drastically raise their blood glucose levels which will hinder fats being used as energy.³ This can be done by familiarizing oneself with Glycemic Index charts and understanding how to calculate Glycemic Load which was described in the previous article. Moreover, lipids help regulate the speed of digestion which can assist in maintaining a steady blood glucose response.⁴

Looking at unsaturated fats, these come in two varieties: monounsaturated (think olive oil, almonds, avocados) and polyunsaturated (Omega-6’s i.e. vegetable oils, omega 3’s i.e. salmon, etc.)..⁵ Unsaturated fats are typically considered to be better options for maintaining healthy blood pressure and cholesterol levels.⁶ Additionally, unsaturated fats may contribute to raising beneficial HDL which transports cholesterol away from the arteries into the liver where it is processed out of the body.^{7, 8}

This helps to limit/reduce the rate of plaque buildup within the arteries which in turn can prevent their hardening (called arteriosclerosis) as well as ward off hypertension, heart disease, and stroke.^9,10 Sounds like a pretty good deal, right? Say good-bye to pizza pie and hello to avocado! (Important to note, in the typical American diet, Omega-3 is consumed far less than Omega-6. While the ideal ratio should be between 2:1 and 4:1 in favor of Omega-3, it can be as lopsided as 1:20 in favor of Omega-6!11 Incorporating more foods like cold-water fish, garlic, olive oil, and walnuts in addition to limiting fast food can help even out this unbalance.)¹²

Saturated fats are commonly viewed as the less noble acquaintance of unsaturated fats. As opposed to unsaturated fats, they are usually solid at room temperature and contribute to unhealthy cholesterol levels (elevating LDL which transports cholesterol to the arteries¹³) potentially increasing arterial plaque buildup.¹⁴ Ideally, saturated fat intake should be limited. However, there are some foods with higher saturated fat content, that when eaten in moderation, can be healthy. For example, though dark chocolate is higher in saturated fat, it is a great source of antioxidants, boosts cardiovascular health, and may improve “cognitive function.”¹⁵ Common sources of saturated fats include cheese and dairy products, coconut oil and red meats, eggs and many processed foods.

Turning to trans-saturated fat, we find the real villain in the room (insert an evil laugh here). While there are a few naturally occurring sources of trans-fat, most often, trans-fat is artificially created and can be commonly identified in foods containing partially hydronated oil.¹⁶ Essentially, do your best not to eat this stuff – nuff said. But in all seriousness, trans-fat is like saturated fat on steroids both raising LDL and lowering HDL potentially leading to cardio complications and stroke.¹⁷ Trans-fat. Just Don’t Do It.

In conclusion, fats are a crucial element of one’s diet. Generally, unsaturated fats should constitute the majority of fatty acids one consumes, but in moderation, foods with saturated fats can provide health benefits. And no, eating dietary fat does not solely contribute to unwanted weight gain. Weight gain occurs from a combination of eating more calories than one uses throughout the day and the nutritional quality of foods eaten. While there are many more nuances regarding how specific, fatty acids impact one’s health, the information presented offers a good start for making informed, dietary decisions. Until next time, lipid to the fullest!

Written by: Michael Hollinger, CPT

Citations

1. Austin, Krista & Seebohar, Bob; Performance Nutrition: Applying the Science of Nutrient Timing; Human Kinetics, 1st Edition (2011)
2. Ibid.
3. Ibid.
4. NASM Essentials of Personal Fitness Training, 6th Edition; Jones and Bartlett Learning (2017)
5. Ibid.
6. Ibid.

7, 9. Unsaturated Fats: Types, Health Benefits and Sources (healthpedian.org)

11. Omega-6 vs. Omega-3 Fatty Acids: What You Should Know | University Health News
12. Omega-3 and Omega-6: Know the Difference | BrainMD Life
13. Cholesterol: Understanding HDL vs. LDL – Harvard Health
    8, 10, 14. LDL & HDL: Good & Bad Cholesterol | cdc.gov
14. 9 Benefits of Dark Chocolate and Nutrition, Recipes, Side Effects – Dr. Axe (draxe.com)
    16-17. Trans Fats | American Heart Association