Fats can get a bit of a bad rap, and the dangers of a ‘high fat’ diet are often attributed to health issues such as cardiovascular disease, high cholesterol, diabetes and obesity. But the concern shouldn’t be about fat in general, but rather the type of fats you should be choosing to include in your diet. Fats have many important jobs to perform in the body and are vital to our health.
Functions of Fats
- Energy – fats supply the body with stored energy, and are utilised once the body burns any carbohydrate sources. Fats contains twice the amount of energy per gram compared with carbohydrates and protein.
- Cell membranes – our cell membranes are made up of a phospholipid bilayer, derived from fats.
- Skin health – our sebum, secreted by the sebaceous glands, is primarily made of up fat and protects our skin and mucous membranes.
- Hormones – such as our sex hormones and stress modulating hormones are manufactured from cholesterol & fats.
- Fat-soluble vitamins – dietary fat is essential for the digestion, absorption and transport of fat-soluble vitamins such as Vitamin A, D, E & K.
- Insulation – stored fats in adipose tissue protect our organs and help to regulate our body temperature.
Types of Fats
- Trans Fat - Processed, deep fried and ‘fast foods’ which contain trans-fats should be avoided, as they can increase levels of LDL (or ‘bad’) cholesterol in the body, and contribute to the development of atherosclerotic plaques and heart disease.
- Saturated fat – Saturated fats are primarily found in meat, dairy products, and processed foods including biscuits, cakes and pastries and should be consumed in moderation, as little as 10% of the total dietary energy intake or less. The Heart Foundation recommends that they should be reduced to 7% of the total energy intake. Saturated fats may contribute to higher amounts of LDL (bad) cholesterol, though having said that, meat and dairy products contain protein and vitamins and minerals that are important to health. They are required for hormone signalling, to enhance mineral absorption and carry fat soluble vitamins around the body. The key here is eating in moderation.
- Polyunsaturated Fat - Polyunsaturated fats such Omega 3 & 6 fatty acids are the building blocks of cell membranes and regulate inflammatory processes in the body, and should be included as part of a healthy balanced diet. These essential fatty acids can’t be made by the body, and need to be consumed from the diet.
Sources of healthy fats
Foods that provide a source of polyunsaturated fats and essential Omega 3 & 6 fatty acids include:
- Avocados.
- Raw nuts and seeds.
- Nut butters and Tahini.
- Olives and olive oil.
- Egg yolk.
- Oily fish such as salmon, sardines, mackerel, herring.
- Cold pressed nut and plant oils such as flaxseed oil.
How much fat should I consume daily?
The current recommendation by the National Health and Medicine Research Council for the percentage of energy from our diet should be 20-35% derived from fat with no more than 10% of this coming from saturated fat. For men aged over 19 years to consume 160 mg/day and women aged over 19 years to consume 90 mg/day polyunsaturated fatty acids including omega 3 and omega 6 fatty acids.
