Fats: Understanding The Importance of Healthy Fats
Updated Mar. 18th, 2024 | Read Time: 6 Minutes | What You Will Learn:
- What Are Healthy Fats?
- Exploring The Different Types of Fats
- Fatty Acids
- Triglycerides
- Phospholipids and Cell Membranes
- Saturated vs Unsaturated Fats
- How To Properly Cook With Fats
- The Truth About Low Fat Diets
- Understanding Healthy Essential Fats
- How To Balance Healthy & Unhealthy Fats Through Diet & Supplements
Since the 1980’s there has been a common focus on low-fat diets to promote weight loss. It has only been in the last few years that people have begun to question whether cutting fat is the answer to weight loss. We have started to question whether low-fat is healthy at all. Research has indicated that, like most things in life, healthy fats are actually very good for you in reasonable amounts, and only become bad for you in excess. So once again, moderation is key.
What Are Healthy Fats?
The proper scientific term for fats is actually “lipids”, which are carbon-based substances that are naturally insoluble in water. Hence the adage “oil and water don’t mix”. Lipids that are solid at room temperature are usually referred to as “fats” while those that are liquid at room temperature are generally referred to as “oils”. The basic subunit of any lipid is fatty acids.
Exploring The Different Types of Fats
Fatty Acids
A fatty acid consists of a carboxylic acid group with a long carbon chain tail. In nature, there is usually an even number of carbon atoms in the fatty acid chain. In the human body, fatty acids are bound to other molecules to perform a function. If they are unbound, they are called “free fatty acids”.
Triglycerides
Free fatty acids are uncommon, and usually, we find our fats in triglyceride form in the food that we eat. Triglycerides are composed of three fatty acid chains bound to a glycerol backbone. When you eat fats, the digestive enzyme, lipase, in your small intestine cleaves the fatty acids off of the glycerol backbone so they can be absorbed into your system.
Phospholipids and Cell Membranes
When you absorb free fatty acids, they can then be used to form phospholipids. Interestingly, each one of your cell membranes is entirely made up of a double layer of phospholipids. Each phospholipid is made up of a polar phosphate molecule bound to two non-polar fatty acid chains. The structure of these phospholipids allows the polar heads to face the water both inside and outside the cell, while the fatty acid tails attract to one another and create the lipid centre of the cell membrane. This lipid centre helps to prevent polar molecules from drifting into your cells. Cholesterol is also used in your cell membranes to help anchor messenger proteins and receptors.
Saturated vs Unsaturated Fats
Society has decided that we should avoid all saturated fats at all costs. Have you ever wondered why? First, we should go over the difference between saturated and unsaturated fats.
Saturated fats
Every carbon atom in each fatty acid chain is fully bound (or “saturated”) with hydrogen atoms, leaving no space for double bonds. They are relatively straight chains, allowing them to all closely line up next to one another. Tightly packed molecules form solid substances at room temperature. Thus saturated fats are the lipids that we tend to call “fats”, like butter and coconut oil. When these fats are incorporated into your cells, they create more rigid cell membranes. This means that your cells cannot easily flex and adapt. In your blood vessels, when these fats accumulate, they create a more solid plaque. Thus, diets high in saturated fat can cause an increased risk of cardiovascular disease, and the poor skin flexibility associated with aging.
Unsaturated Fats
Unlike saturated fats, unsaturated fats are made up of fatty acids that contain double bonds. These double bonds create “kinks” in the fatty acid chain. Monounsaturated fatty acids have one double bond (mono = one), while fats with more than one double bond are called polyunsaturated fatty acids. The more kinks (double bonds) a fatty acid contains, the harder it is for that fatty acid to get close to its neighbour. When molecules are more spread out, they form a liquid at room temperature. Thus, these unsaturated fats are the lipids that we tend to call oils (like Fish Oil and Almond Oil). When unsaturated fatty acids are used to make the phospholipids in our cell membranes, they become more pliable and able to adapt. This keeps our cardiovascular system and skin, more healthy and flexible.
How To Properly Cook With Fats
Smoking Point
When deciding which fats to use in your cooking, be sure to check out the smoking point. This is a measure of the temperature at which a triglyceride will break apart into its constituent pieces. When glycerol is unbound in the presence of heat, it can then be further broken down into the substance that physically makes the smoke. For deep-frying or other high-temperature cooking methods, it is essential to use oils with a higher smoking point to prevent excess breakdown during cooking.
Cooking with Lipids - Oxidation
From the above information, it seems obvious that unsaturated fats with high smoking points are the way to go for boosting health in your cooking, as with anything, there is always a trade-off. Yes, your diet should always contain a far larger percentage of unsaturated fats than saturated fats to ensure cell flexibility and to protect your cardiovascular system.
So why eat saturated fats at all? Well, when cooking with fat, it can sometimes be more beneficial to use saturated fats. Because the double bonds in unsaturated fats become vulnerable to oxygen attack when heated, unsaturated fats quickly become oxidized in the presence of heat and air (the conditions of cooking). Oxidized fats are extremely reactive and act like free radicals in the body. Free radicals are unstable molecules with an unpaired electron that are extremely reactive, and damage surrounding cell membranes, fats, and fat-soluble vitamins and nutrients. Saturated fats can bypass this risk of oxidation, because they do not have double bonds, and thus will not so easily oxidize during cooking. Thus, saturated fats like butter and Coconut Oil can be beneficial when used in smaller amounts in particular cooking circumstances. This is especially true if the rest of your diet is well balanced with sufficient polyunsaturated fats to help counter its rigid effects.
The Truth About Low Fat Diets
While low-fat diets were all the rage in the 80’s and 90’s, more recent research has found that diets lacking sufficient fat do not result in sustained weight loss. Eating sufficient fat helps our body to produce sufficient hormones, repair body tissues and secrete skin-protecting sebum and other beneficial secretions. They are necessary for our everyday processes, and when present in our diet, they help to ensure the gallbladder is properly flushed to help prevent the formation of Gallstones.
Understanding Healthy Essential Fats
While your body naturally can convert most forms of fat into one another as you require, there are some that we cannot synthesize. These fatty acids must be ingested in your food to meet your body’s needs.
In humans, alpha-linolenic (an Omega 3 Fatty Acid) and linoleic (an Omega 6 Fatty Acid) are the only two essential fatty acids. Three others are only conditionally essential, meaning that they are only essential in certain circumstances. These include examples of Omega 9 Fatty Acids.
How To Balance Healthy & Unhealthy Fats Through Diet & Supplements
While it is obvious that the average North American diet is far too high in fat, especially saturated fat, we must be careful not to throw out the baby with the bathwater. When aiming for a healthy diet, it is important not to eliminate any one nutrient, fats included. Instead, we must aim to use the right amount of fat and the correct fat for our particular needs.
Current research has suggested that the average diet contains between 20-35% of your calories from fats. Each gram of fat contains about 9 calories of energy for the body. This means that for a 2,000 daily calorie diet, this would amount to 400-700 calories or about 44-78g of fat daily. You can adjust this number according to your caloric needs. The correct balance of Omega 3-6-9 is essential, so if your diet is high in one type, be sure to ingest more of the others to rebalance your body.