Fats serve a variety of functions within the human body including hormone production, cellular membrane formation and even function as an energy source (1,2). There are a variety of different types and sub types of fat which creates a lot of confusion. The three main types of fat include unsaturated, saturated and trans. What are the good types? What are the bad types? Which ones cause cancer and which one’s cause heart disease? These are some of the questions that have been posed due to the lack of clarity on the different types of fats and their function. Within this article we will take a look into the different types of fats, their functions and hope to dispel some of the myths on the topic!
What separates unsaturated fats from saturated fats is the carbon placement within the molecule. In unsaturated fats there are double bonds in the fatty acid chain, whereas saturated fats lack these double bonds. Therefore, unsaturated fats are liquid at room temperature and are generally considered as “healthy fats”. Unsaturated fats have two more sub divisions 1.) monounsaturated where there is only one double bond present and 2.) poly unsaturated where more than one double bond is present. Ultimately, these differences in carbon placements effects breakdown and utilization.
Monounsaturated fats are common in oils and nuts such as olive oil, canola oil, almonds, cashews and whole milk. Monounsaturated fats have been shown to play a significant role in heart health. Several investigations have demonstrated that individuals who consume more monounsaturated fats compared to saturated fats are at less risk for developing cardiovascular disease (3-6). Monounsaturated fats especially olive oil is rich in oleic acid a fatty acid which has been shown to have anti-inflammatory properties (7). It is this fatty acid that most researchers attribute the cardio protective effect of mono-unsaturated fats too.
Examples of monounsaturated fats
- Olive oil
- Canola oil
- Peanut butter
- Almond butter
Similar to mono-unsaturated fats, poly unsaturated fats also have impressive health benefits. The two most popular poly-unsaturated fats include omega-3 fatty acids and omega-6 fatty acids. Omega-3 fatty acids have been shown to improve neural development, reduce inflammation and reduce blood pressure (8-10). Additionally, omega-3 fatty acids have been shown to improve symptoms of depression and anxiety (11)! The three main types of omega-3 fatty acids include ALA, EPA and DHA, while EPA appears to be the most effective. Most of the benefits associated with omega-3 fatty acids link back to its ability to fight inflammation primarily due to its ability to reduce the production of key inflammatory markers.
Omega 6 fatty acids on the other hand also serve vital functions including aiding in hormone production and brain health however they are not needed as much as omega 3’s and unfortunately if present in large quantities may increase inflammation (12). The key here is the ratio between omega-3’s and 6’s Currently, the average American ratio is around 16 (Omega 6) : 1 (Omega 3). This could be detrimental, and an ideal ratio is around 4:1 and some argue even lower around 2:1 or even 1:1.
Example of foods sources high in poly-unsaturated fats
Poly unsaturated fats rich in Omega 3’s
Poly unsaturated fats rich in Omega 6’s
- Corn oil
- Soy beans
While in the past saturated fats were labeled as “un-healthy” and directly linked with cardiovascular disease there has been a retraction in these fears within the scientific community (13,14). While, reducing the amount of saturated fat and replacing it with un-saturated fat has been reported to improve health parameters saturated fats themselves are not bad. Additionally, the association between cholesterol levels and heart disease is not as direct as once believed. Okay… now that that’s taken care of let’s dive into some of the specific health benefits of saturated fats.
Saturated fats are classified based on their carbon length ranging from 6 carbons to 18 carbons long! Some of the longer chain fatty acids 14-18 carbons in length have been shown to increase the amount of LDL or bad cholesterol (15). However, medium chain triglycerides (6-12 carbons long) (MCT’s) are broken down differently compared to longer chain fatty acids.
MCT’s are broken down by the liver and metabolized quickly providing you with an immediate energy source! MCT’s have been shown to have a variety of health benefits and have gained a lot of attention in research as well as the media. Evidence based health benefits of MCT’s include increased weight loss due to an increase in calories burned at rest, increased insulin sensitivity, increased cognition in patients with neurodegenerative diseases as well as anti-seizure effects for patients with epilepsy (16-18). Lastly, MCT’s appear to rapidly increase ketone production and provide an anti-microbial effect which may be beneficial for those following a ketogenic diet (19,20)!
Sources of Saturated Fat’s
- Dark chicken
- Whole milk
Sources of MCT’s
- Coconut oil
- MCT oil
- MCT bar
- MCT powder
- Palm kernel oil
- Whole milk
Last up we have trans-fat which are made by heating up vegetable oils via hydrogenation. This was initially done in an attempt to improve the shelf life of foods. Trans fat are commonly found fried foods and packaged goods and margarine. Trans fats are a BAD type of fat! Diet high in trans-fat have been shown to increase LDL (bad cholesterol) and lower (HDL) good cholesterol, increase inflammation and increase insulin resistance! These should be avoided at all cost! While trans-fat has been banned in most establishments you should still keep an eye out and ensure that you’re not taking any in (CITE).
Sources of trans fat
- Baked goods
- Breakfast pastries
- Fried foods
- Packaged snacks
- Fast food
Wrapping it up
Well there you have it fats explained! Fats are involved in a multitude of bodily processes including hormone production, mood stabilization, membrane formation and energy production. The main breakdowns of fat include unsaturated (mono and poly), saturated (c6-c18), and trans. Previously, it was thought that fat’s are bad especially saturated fats and while more research is needed there no strong links between saturated fat and heart disease as once thought. In fact, certain types of saturated fats like mct’s (C6-12) have impressive health benefits. Trans fats on the other hand were designed to increase the shelf life of foods and have shown to be detrimental to health. Now next time someone brings up fats at the dinner table rest assured that your well equip to join in and set the record straight!