Fats can be one of the most confusing things to consider in relation to our diets. We constantly hear how fat is bad for you and are bombarded with low-fat and fat-free messages in food advertisements and food packaging. Fat has become a word with many negative connotations.
The truth is, not all fats were created equal, the wrong type of fat can raise our blood pressure and ‘bad’ LDL cholesterol, which increases the risk of heart disease and other chronic diseases. The right kind of fat is essential for our bodies to function properly and can actually lower bad cholesterol and the risk of heart disease and cancer.
There are different types of fats. For example, your body converts the excess glucose (from carbohydrates) in your tissues into a certain type of fat. The fat found in plants and animal products is called dietary fat, and this is the type we are about to explain.
It’s been believed for a long time that low-fat or fat-free diets can control weight and reduce the risk of heart disease or other chronic illnesses. However, products which are fat-free or have reduced fat normally compensate for flavour and texture with salt, sugar and refined grains. What really matters is the type of fat in our diets.
The fact is, we all need some fat in our diets as it helps the body absorb certain nutrients and is essential for cell structure because it forms part of each cell’s membrane, helping it keep it’s shape. Fat is also a source of energy as it provides important vitamins and essential fatty acids that the body can’t produce itself. The trick is to understand the different types of fats, where they come from, why they are good or bad for you, and then make an educated decision as to which fats to include in your diet.
SO, WHAT IS FAT?
Fat makes food taste rich and heavy. Fat is the oil, the grease, the lard, the creamy inside of an avocado. Fat doesn’t dissolve in water – you may have noticed how the water is repelled when you run it over a greasy pan. Fat can line the insides of your blood vessels without getting washed away, or it can maintain the structure of your cells, depending on which kind of fat it is. The two main types of fats are saturated fat and unsaturated fat… but there is also another nasty type of fat, a man-made one called trans-fatty acid.
Generally, saturated fat is solid at room temperature and turns to liquid when heated up. Animal fats, processed meats, lard, margarine and ice cream all contain saturated fat (mostly from animal products). It’s called saturated fat because every empty space in its chemical structure is filled (saturated) with a hydrogen atom. The hydrogen makes the fat solid and this is what makes it bad for you. Too much saturated fat increases the levels of ‘bad’ LDL cholesterol in your body, which can cause heart disease. It can also lead to obesity and cancer.
However, not all saturated fat is bad for you. About half the saturated fat in coconut oil is made up of a fat rarely found in nature called lauric acid. It digests easily and promotes a healthy heart by boosting ’good’ HDL cholesterol. It is known to destroy certain viruses and bacteria, help with weight loss, support the immune system and keep your skin healthy.
There are two types of unsaturated fat: monounsaturated and polyunsaturated. Monounsaturated fat is missing just one (mono) of the hydrogen atoms (compared to saturated fat), which makes it liquid at room temperature. Polyunsaturated fat is missing more than one hydrogen atom (poly means many), which means it stays a liquid unless it freezes.
Unsaturated fats provide vitamins and nutrients which help develop and maintain normal cell structure. Having healthy cells means having a healthy body. Unsaturated fats have been shown to protect against chronic diseases such as heart disease and cancer. They also help to raise levels of ’good’ HDL cholesterol and lower ‘bad’ cholesterol, and they help to stabilise blood sugar levels.
Foods that are rich in unsaturated fats also provide essential fatty acids, which are essential because our bodies cannot produce them, so we can only get them from our diets, and they are an essential nutrient for all the tissues in the body.
ESSENTIAL FATTY ACIDS
Essential fatty acids, or EFAs, are types of polyunsaturated fatty acids that are an important nutrient for all tissues in the body. They are essential to our reproductive, cardiovascular, immune, and nervous systems to name a few, so it’s important we include them in our diets.
There are two main kinds of EFAs, commonly known as omega-3 and omega-6 fatty acids. Foods high in EFAs pack a nutritional punch because they are generally loaded with vitamins, minerals, phytonutrients and many other antioxidants. Deficiencies in EFAs lead to a weakened immune system, growth problems and liver and kidney problems.
OMEGA-3 FATTY ACIDS
Omega-3 performs a number of important roles in the body, including helping organs to function properly. It is used in the formation of cell walls and helps to circulate oxygen throughout your body. It helps in the prevention of heart disease, high blood pressure, high cholesterol, arthritis, skin conditions and diabetes. It manages inflammation and maintains the normal structure of every cell, as well as aids healthy brain function.
Omega-3 can be found in many plant-based foods such as beans (mung and soy), seeds and nuts (walnuts, flax, hemp, chia and pumpkin seeds), oils (flaxseed and linseed), eggs and fruit and vegetables. It can also be found in oily fish such as salmon or tuna.
OMEGA-6 FATTY ACIDS
Omega-6 fatty acids reduce the risk of heart disease, help with skin problems, fight cancer cells and treats arthritis. Most people get plenty of omega-6 in their diet, sometimes too much. Omega-6 fatty acids compete with omega-3 fatty acids for use in the body, so too much omega-6 can inhibit the effective use of omega-3 by the body. Omega-6 is found in leafy vegetables, avocados, seeds and nuts (Brazil nuts, almonds, pistachios, pine nuts), whole grains, eggs, and vegetable oils (corn, soybean, cottonseed, sesame, sunflower).
Trans-fatty acids are the worst kind of fats for your body. This type of fat occurs naturally in some foods in small amounts (like meat and dairy), but mostly they are created by food manufacturers through a process called partial hydrogenation. This process involves taking unsaturated oil (the vegetable one that’s missing some hydrogen atoms) and forcing hydrogen into the empty spaces. This process turns the previously liquid unsaturated oil into more solid trans fats.
This is done for two main reasons: firstly, it is easier to cook with trans fats as the oil boils at a higher temperature which is better for deep frying, and the second reason is… shelf life. Solid fats don’t spoil as quickly as unsaturated fats do, which means that crisps and other processed foods can sit on the shelf for a lot longer without going bad. Studies show that these partially hydrogenated trans fats can increase ‘bad’ (LDL) cholesterol and lower ‘good’ (HDL) cholesterol. This can increase your risk of cardiovascular disease and many other illnesses.
The main source of trans-fatty acids is processed foods such as biscuits, cakes, crisps, margarine and fried foods (to name a very few).
With different types of fats – some good, some bad – it can get confusing working out what you should and shouldn’t eat, but don’t worry about the percentages and big words on food packages too much. In general, you can bet that any food that’s part of a plant, even if it contains a lot of fat (like olives or nuts), is probably good for you; and any highly-packaged, refined food or high-fat animal product probably isn’t.