Trans fats. The name may strike fear into your heart, literally and figuratively. But are these highly publicised fats as bad as you think? We’ve asked the questions to find out all you need to know.
1. What are trans fats and do they occur naturally in foods?
Trans fats, which are also known as trans fatty acids, partially hydrogenated oil and hydrogenated oil, are a type of fat formed when liquid vegetable oil is hardened by treating it with hydrogen. This hydrogenation process changes vegetable oil from an unsaturated fat into a harmful fat that affects the body in much the same way as saturated fat. Trans fats also occur naturally in dairy products, beef, veal, lamb and mutton – but in very small amounts.
2. Which products contain trans fats in larger amounts?
Manufactured trans fats occur in high levels in many processed food products such as pies, cakes, desserts, processed noodles, pasta and some margarine.
3. Why are foods with trans fats harmful to our health?
Of all the fats that occur in food, trans fats are the most dangerous. Trans fat increases the ‘bad’ or LDL cholesterol in our blood in the same way as saturated fat does but, on top of this, it also decreases the HDL or ‘good’ component of cholesterol, making it very harmful to heart health. A high intake of trans fats is associated with a number of medical conditions, such as type 2 diabetes, obesity, cardiovascular disease and stroke.
4. Can we consume a ‘safe’ amount of trans fats?
It is recommended that we consume no more than 1% of our kilojoules from trans fats. On average, we require about 8 000 kilojoules per day – 1% of that is 80 kilojoules or 2.2g of trans fats. However, eating just one meat pie or doughnut or a serving of hot chips per day would push you over the limit.
5. How can you avoid consuming trans fats?
The easiest way to avoid consuming trans fats is simply to decrease your intake of highly processed ‘treat’ foods such as cakes, pastries, biscuits and fried foods. These are likely to be high in both saturated and trans fats. Instead, snack on foods that are more nutritious and filling such as fresh fruit or raw unprocessed nuts. Read food labels on packaging and avoid any products that list ‘vegetable oil’, ‘hydrogenated oil’ and ‘partially hydrogenated oil’ in the ingredients.
6. What about the consumption of saturated fats?
Often our trans fats consumption is nowhere near as alarming to health experts as our levels of saturated fat consumption. As a guide, remember that the recommended daily allowance for saturated fat in your diet is 9% of your total kilojoules.
Know your fats
- Polyunsaturated fats: Healthy fats that help lower your blood cholesterol. Found in polyunsaturated margarine, sunflower oil, soybean oils, fish, walnuts, hazelnuts, brazil nuts and seeds.
- Monounsaturated fats: Can help lower blood cholesterol. Found in monounsaturated margarine; canola, olive and peanut oils; peanuts; cashews; almonds; seeds and avocados.
- Unsaturated fats: …that behave like saturated fats in the body because of their chemical structure. They raise ‘bad’ blood cholesterol levels and decrease ‘good’ cholesterol levels. Found naturally in small amounts in dairy products and most meat, but primarily in baked and fried foods.
- Saturated fats: Raise the blood cholesterol levels in the body. Found in fatty meats, full-fat dairy products, butter, coconut and palm oil, most deep-fried takeaway food, and baked products such as biscuits and pastries.