Fats are an essential part of a healthy diet, however, only a small amount of healthy fats are needed for good health. Fat provides the highest amount of energy (kilojoules) per gram compared to any other nutrient. A diet high in fat will be high in energy (kilojoules) that can lead to weight gain.
Fats and cholesterol
Cholesterol in food makes a small different to cholesterol in blood. Instead it is the saturated fats and trans fats (unhealthy fats) found in food can increase blood cholesterol. Unsaturated fats (healthy fats) assist to lower blood cholesterol.
High cholesterol can be a risk factor for heart disease. (click here to high cholesterol content).
Unhealthy fats - Saturated and trans fats
Unhealthy fats include saturated and trans fats. These fats lead to the production of LDL (bad) cholesterol in the blood that can build-up and create ‘plaque’. Overtime the plaque can build-up, narrowing the block vessel or forming blockages, which can lead to heart disease. Reducing the amount of saturated fat in the diet can assist to lower the levels of LDL-cholesterol.
Foods high in saturated fat include:
- Full fat dairy products (full-fat milk, full-fat yoghurt).
- Butter, lard, ghee.
- Hard and full fat cheese.
- Fat on meat, marbling in meat.
- Chicken skin.
- Processed meats (sausages, salami).
- Pastries, pies.
- Coconut oil, coconut milk, coconut cream.
- Palm oil – palm oil is cheap fat therefore often found in processed foods i.e. chips, supermarket baked goods.
- Fried and fatty takeaway.
- Packaged cakes and biscuits.
Trans fats (also known as trans fatty acids) are unsaturated fats that have been processed and changed so they act like saturated fats. They are made when vegetable oils are heated (partially hydrogenated or hardened) so they become a solid at room temperature. Trans fats increase the levels of LDL cholesterol and reduce the levels of HDL cholesterol.
Trans fats are uncommon in nature but may be found in low levels in the fat of beef, lamb and dairy foods. Most often, they are found in deep fried fast food, takeaways, commercial biscuits and pastries.
Trans fats can increase the LDL (bad) cholesterol and reduce HDL (good) cholesterol levels in the blood, a key indicator for heart disease.
To limit your trans fat intake and maintain a healthy diet:
- Limit your intake of manufactured foods such as biscuits and pastries.
- Avoid deep fried fast foods and takeaway.
- Use margarines that list trans fat as < 0.1 g per 100g.
- Choose low-fat dairy foods.
- Trim visible fat from meat and skin from chicken
Triglycerides are a type of fat found in vegetable and animal fat and account for almost 95% of all dietary fat. When consumed, triglycerides circulate in the blood to be used by cells for energy. When you are active or exercise, triglycerides are burnt for fuel, however, when you are inactive triglycerides that are not burnt are stored in fat cells. Eating more energy than you burn is a common cause of high triglycerides and weight gain, which can contribute to heart disease. Excessive alcohol intake also contribute to high triglycerides.
Healthy fats - Mono-unsaturated/Poly-unsaturated fats (omega-3 and omega-6)
Healthy fats include mono-unsaturated fats, poly-unsaturated omega-3 and poly-unsaturated omega-6 fats. Unsaturated fats reduce blood cholesterol when consumed in place of saturated fats. These fats are protective to the heart by helping to increase the amount of HDL (good) cholesterol, but also reducing the amount of LDL (bad) cholesterol in the blood. These fats should be consumed in moderation.
Foods high in unsaturated fat are mostly plant-based, with the exception of fish. These foods include:
- Mono-unsaturated fats
- Olive, canola, peanut, macadamia oils and margarines.
- Sesame and pumpkin seeds.
- Cashews and almonds.
- Poly-unsaturated omega-3 fats
- Canola oil and margarine.
- Fish – salmon, tuna, sardines, mackerel, herring.
- Include 2 fish meals/week.
- Walnuts and linseed.
- Chia seeds.
- Poly-unsaturated omega-6 fats
- Sunflower, safflower, soybean, corn and grape-seed margarines and oils.
- Walnuts, pine and brazil nuts.
Plant sterols are found naturally in foods, such as sunflower seeds, canola seeds, vegetable oils, and in smaller amounts in nuts, legumes, fruit, vegetables and legumes. Plant sterols have a similar chemical structure to cholesterol; therefore plant sterols substitute for cholesterol in the absorption, and are able to stop cholesterol from being absorbed.
Some food products have been modified to have added plant sterols, including milk, yoghurt and margarine. These modified food products can be effective in reducing LDL cholesterol, just make sure to take the recommended dose for it to be effective. It is recommended to have 2-3g of plant sterols; this is equivalent of 2-3 serves of foods modified with plant sterols6. One serve of plant sterol enriched-food is considered to be:
- 2 teaspoons of margarine.
- 250ml milk.
- 200g yoghurt.
These modified products are sometimes more expensive than equivalent products not enriched with plant sterols and therefore might not be suitable for every budget.
Tips to lower cholesterol
Limit intake of saturated and trans fat.
- Trim visible fat off meats, remove skin from chicken.
- Choose lean meats.
- Avoid processed meats and small goods.
- Choose reduced-fat/low-fat/skim milk, yoghurt, ice-cream, cream, custard and cheese.
- Limit intake of pies, pastries, sausage rolls, cakes, biscuits, chocolate and cream biscuits.
- Use thin spreads of margarine instead of butter.
- Choose tomato-based sauces instead of cream sauces.
Choose monounsaturated and polyunsaturated fats in place of saturated fats.
- Use margarine instead of butter.
- Aim for 2 fish meals/week.
Eat plenty of fruit and vegetables.
- Aim for 2 serves of fruit and 5 serves of vegetables/day.
- Consume handful of nuts (30g) five times a week.
- Increase your fibre intake by choosing whole grain foods.
- Limit alcohol intake to 1-2 standard drinks/day.
Enjoy a healthy lifestyle
- Maintain a healthy weight for your age and height. Check with what a healthy weight is for your age and height with your doctor or dietitian.
- Aim for 30 mins of moderate intensity exercise at least 5 days/ week. Vigorous exercise will have additional health benefits. Check with your doctor before you start.
- The Dietitians Association of Australia, ‘Fat’, viewed 19 March 2013
- Diabetes and Food: Healthy Eating for diabetes, SA Health
- Borushek, A 2011, Calorie Fat & Carbohydrate Counter, Family Health Publications, WA
- Baker IDI Heart and Diabetes Institute 2012, ‘Making healthy meals’, viewed 31 May
- Nuts for Life 2005, ’10 ways to lower cholesterol’, viewed 31 May 2013, http://www.nutsforlife.com.au/index.php?option=com_content&task=view&id=64&Itemid=84
- Baker IDI Heart and Diabetes Institute, ‘Cholesterol and your health’, viewed 11 June 2013, http://www.bakeridi.edu.au/health_fact_sheets/cholesterol_your_health
- Better Health Channel, State Government of Victoria 2013, ‘Triglycerides’, viewed 11 June 2013, http://www.betterhealth.vic.gov.au/bhcv2/bhcarticles.nsf/pages/Triglycerides?open
- National Heart Foundation 2009, ‘Position statement: Phytosterol/stanol enriched foods’, viewed 11 June 2013
- Food Standards Australia New Zealand 2011, ‘Plant sterols’, viewed 11 June 2013, http://www.foodstandards.gov.au/consumer/nutrition/plantsterol/Pages/default.aspx