Fats are either saturated or unsaturated. Know the difference? by Goodhealth

Fats are either saturated or unsaturated. Know the difference?

Tháng Tư 17, 2023

Without trying to change the world with one blog post, we thought it’d be a good idea to break down this complex topic and dispel some of the myths around fats to let you know why it’s so vital you include them in your diet.

It seems that for a long time there has been a bit of a stigma around the word ‘fat’ and that it’s not exactly considered a best friend when it comes to food. While this is true of some fats, there are others that are hugely important to your diet and health (they aren’t called ‘essential’ for nothing!).

Because fatty acids are essential to life on earth, every food we eat will contain fat, even if, in the case of some fruits, the amount is around 0.001%. And every fat in every food will be a combination of saturated, monounsaturated, and polyunsaturated fatty acids, in varying ratios. There is a myriad of short, medium, and long chain fatty acids, within the 3 levels of saturation, e.g., stearic, palmitic, lauric, butyric, linoleic, arachidonic (Omega-6), and docosahexaenoic (DHA – Omega-3), to name but a few! The Omega-6 and 3 fatty acids are considered essential because we cannot make them in our body. Omega 3 has a positive effect on our cardiovascular health and it also is very good at supporting a healthy immune response.

A saturated fat

…is so-called because, at a molecular level, the carbon bonds are fully “saturated” with hydrogen atoms. This makes saturated fatty acids generally firm and solid at room temperature, not prone to oxidation, and very stable to cook with. The most stable fats are the ruminant (cow, sheep, etc) fats like tallow, suet, and the fat on red meat. Butter and ghee are also stable, although the milk proteins left in butter can cause the butter to burn when frying. To call these fats “saturated” is to ignore the monounsaturated and polyunsaturated components of the fat, as a whole. For example, Beef fat is, on average, about 50% saturated, 45% monounsaturated, and 5% polyunsaturated – a perfect ratio for human health.

Contrast that with unsaturated fats,

which are usually liquid at room temperature, prone to oxidation, and very unstable. We know them as fruit oils like olive, avocado, and coconut oil, or seed/vegetable oils like flaxseed oil, soybean, rice bran, and canola. Olive oil is a fruit-derived lipid (fat) and is approximately 73% monounsaturated, 14% saturated, and 11% polyunsaturated. Coconut oil is the most saturated fruit fat, with around 90-92% saturated, 6-8% monounsaturated, and the balance, polyunsaturated.

For a while now, due to incomplete and inaccurate science undertaken in the middle of last century, the thinking has been that there was a benefit of using unsaturated fat over saturated fat because it is “better for heart and cardiovascular health”. This was because eating unsaturated oils “lowered cholesterol levels” in the blood. We now know that cholesterol is not the cause of problems, in and of itself.

What makes polyunsaturated oils

…more dangerous to our heart health is that when they are heated the oil oxidises, producing free radicals, which can damage arteries. They’re called vegetable oils, but they have little to do with vegetables, as such. They are extracted from seeds, and most are industrially processed oils, the processes creating toxic chemicals within the oil. Hydrogenated oil, found in margarines, etc, is altered to behave like a saturated fat – to be solid at room temperature, and is the most dangerous because it becomes a trans-fat. While a small amount of cold-pressed, organic seed oil, is ok, ditch the margarine and stick to butter! Use other animal fats (and some coconut oil) for cooking, and olive oil and whole avocado for salads, mayos, etc.

Another reason vegetable oils should be avoided is because they contain relatively high levels of linoleic acid (LA), an omega-6 fatty acid. Small amounts are present in traditional foods, but with vegetable oils in almost all processed foods, our modern diets are far too high in LA. The issue with excess LA is complicated but the main problems are how easily it oxidises, how it competes with Omega-3s for metabolism, its harmful breakdown products (OXLAMS and aldehydes), and how it hijacks satiety levels through cannabinoid receptor activation in the gut.

Vegetable oils also contain phytosterols, which compete with cholesterol for use in the body. Cholesterol is essential for life and around 80% of Cholesterol is made in the liver. Cholesterol is so important that the brain makes its own.

Fats can be utilised as a fuel, just like glucose, but in a different way in our mitochondria (cell powerhouses). A healthy metabolism is not overloaded with energy and able to switch between these 2 fuel sources, without too much trouble.

The important thing to remember is that fats are an important part of our diet and should be eaten in whole food form, not in the form of industrially produced oils. Eating natural, animal fats is not bad and, in fact, could be the very thing that made us human. They contain fat soluble vitamins, A, C, D, and E, and are very stable and contain many little-known, healthy fatty acids like CLA, and odd-chain FAs.

Dietary fat is a much more complex and nuanced topic than most healthcare providers would have you believe. To make things simpler, avoid vegetable oils, especially if they’re hydrogenated, as much as possible. These are the fats you would find in processed and junk “foods”. Deep fried foods should be avoided at all costs due to the toxic nature of the vegetable oils when they are heated. If you can find a takeaway bar that still uses beef tallow or pork lard (any kind of meat dripping or rendered fat) to fry with, that is a much healthier choice. At the end of the day, don’t fear the fat (just the oil!).