Fats are a crucial part of our diets and all body systems rely on them for function as they make up cell membranes, insulate organs and even keep our skin waterproofed and healthy. Our brains, eyes, liver and other organs are made of fats. Good mood, mental health and cognitive function rely on a good supply of the healthy kinds from our diets.
Low-fat diets do not provide the fats we need and can lead to poor skin health, hormone and nervous system issues, sugar cravings, poor stress coping and poor healing. Low-fat products often have sugar and chemicals added to make up for the lack of taste and appetite satisfaction that removing the fat creates. Our bodies will still crave that which we need though and may do this in the guise of sugar craving as we can convert sugars into the fats we need when low in our diets. You may find yourself also craving less desirable sources like cheese and chocolate in this case, a scenario vegetarians may see in colder months when we naturally stock up on fat for heat creation.
Understanding the different fats we need and why these are not simply ‘good or bad’, can help us enjoy a rounded, healthy and satisfying diet:
Polyunsaturated fats (or unsaturated fats) – these are often known as oils as they are liquid at room temperature. Two main kinds are omega 3 and 6 oils, often referred to as Essential Fatty Acids as we have to take them in from diet, need them to function and cannot manufacture them ourselves. Omega 6 oils are found in plant sources like nuts, seeds and grains. Whilst those have some omega 3 oils in, those are not easy for us to use. The best direct sources of omega 3s are from oily fish like mackerel and salmon. The modern diet tends to be higher in 6 than 3, which has been associated with inflammation. Vegetarians and vegans can get the direct sources from an algae DHA supplement.
Saturated fats – these are solid at room temperature and generally from animal sources, like butter and goose fat. These have got a bad reputation in recent years, but are necessary for our health as long as balanced with omega 3 oils and without too much sugar in our diets. We need them to make vitamin D, steroid hormones for metabolic function (like oestrogen, progesterone, cortisol and DHEA) and for cell production. There are also some plant sources like those found in coconut, called MCTs (medium-chain triglycerides). Humans can’t store these as fats, we have to metabolise them through the liver immediately, so they actually raise metabolism.
Monounsaturated fats – these are the oils in foods associated with the healthy Mediterranean Diet, like nuts, olive oil and avocados. They are associated with good heart health and cholesterol regulation, with potent anti-inflammatory actions.
Cholesterol – the building blocks of all of our steroid hormones and vitamin D, cholesterol also transports fats around the body to where needed. It can cause issues when becomes out of balance and the LDL kind becomes raised. Rather than just saturated fat, it is the combination of saturated fat and sugar that causes its dysregulation and health issues.
Trans and hydrogenated fats – these are damaged fats found in fried and junk food. They can lead to inflammation and block the healthy action of other fats.
COOKING WITH OILS & FATS – a guide
|Animal fats||Almond||Hemp*||Flax or linseed|
|Palm kernel||Hazelnut||Safflower||also contain super-|
|High heat– 190 C/375 F||Mod. heat-170 C/325 F||Low Heat – 100 C/ 212 F||Cold – up to 49 C/ 120 F|
|More stable in the presence of heat, light and oxygen. Best used for high temperature cooking such as frying. Butter can be clarified to make ghee to remove the harmful milk solids.||Although oils, do not contain essential fatty acids and as more stable are more suitable for medium heat cooking such as sautéing and stir-frying.||Except those with super-unsaturates*- heat sensitive for cold dishes or low temp. cooking such as baking and sauces. For bread and cakes up to 163 C/ 325 F, moisture keeps the inside temp. under 100 C/ 212 F.||Extremely vulnerable to damage from heat – should only be used cold in the preparation of dressings, dips, relishes and mayonnaise.Includes those above*. These ‘essential fats’ need to be stored in dark glass to protect them from oxidisation from heat, light and oxygen.|