Weight loss warriors often follow a low-fat diet to help them shed the kilos. Products labelled low-fat, fat-free and 97% fat-free sound enticing and are marketed as the perfect solution for all your weight woes. But, it’s just like the saying… if it sounds too good to be true, it probably is.
Fats, we love to hate them. Since the 70s, following a low-fat eating plan has been touted as the best way to lose weight, yet the obesity rates have continued to rise. During this time we’ve seen the range of low-fat and fat-free products take over our supermarket shelves – everything from low-fat cakes and biscuits to fat-free lollies and chewing gums. It seems ingenious – enjoying your favourite snack foods, sauces, spreads and bakery goods without the extra kilojoules – but, when it comes to weight loss removing the fat from your food might be the last thing you should be doing to shed those unwanted kilos.
When it comes to low-fat products, it’s not as simple as just taking out the fat. To ensure the product’s taste isn’t compromised and the functionality properties of the fat in a food aren’t lost, other ingredients are added in its place. To maintain the same mouth feel of full-fat sauces, salad dressings, baked goods and frozen desserts, carbohydrate-based fat replacers are used as thickeners, while milk or egg protein are used as protein-based fat replacers in cheese, frozen dairy desserts, margarines, soups and mayonnaise. However, according to research from the Purdue University, these fat substitutes can leave us unsatisfied and actually hinder our weight loss attempts.
In the study from Purdue University, rats were fed Pringles potato crisps – either a high fat variety or a combination of both high-fat and low-fat olestra (a substance that tastes like fat but is not digested nor absorbed by the body) varieties. Rats eating a mixture of the two types of potato crisps consumed more food, gained more weight and developed more fatty tissue than the rats that ate only the high-fat crisps.
According to the researchers, fat substitutes can confuse the body and its ability to regulate food intake, increasing the likelihood of weight gain. How? When we eat fatty food, our body is expecting a large number of kilojoules and the taste triggers a number of responses in the body such as salivation, hormonal secretions and metabolic reactions. But, fat substitutes interfere with this relationship, confusing our brain as no kilojoules arrive. This confusion is thought to interfere with the body’s ability to regulate food intake, which can lead to inefficient use of kilojoules and result in weight gain.
While research in humans is needed to determine whether the same findings occur, additional research has found that many of us perceive low-fat foods as the healthier alternative, which gives us a green light to eat more. This phenomenon is known as the ‘health halo’. While overeating on low-fat foods gives us more kilojoules than we need, many low-fat foods also contain the same number of kilojoules (if not more) than their full-fat counterparts. This is because they have extra sugars added to make up for the loss of taste and poorer mouth feel created when fat is removed from the product. Many low-fat yoghurts are the prefect example of this.
Just a little bit
Including a small amount of healthy fats in the form of plant-based oils, oily fish, nuts, seeds and avocado is important for your health and adds to the enjoyment of food. Here’s why you should be adding just a little bit.
- It boosts nutrient absorption: Adding a fat-rich dressing to a salad boosts the absorption of fat-soluble carotenoids such as lutein, lycopene, beta-carotene and zeaxanthin, says new research published in the journal Molecular Nutrition & Food Research. According to the research, dressings rich in monounsaturated fat require the smallest amount of fat to get the most carotenoid absorption, while dressings rich in saturated fat and polyunsaturated fat required higher amounts of fat to get the same benefits. In fact, just 3g of monounsaturated fat-rich dressings such as olive oil or canola oil-based dressings promoted the same level of carotenoid absorption as a 20g serving of the same dressing did. Drizzle a teaspoon of olive oil on your salad and enjoy the nutrient boost.
- It carries nutrients around the body: Dietary fat helps carry fat-soluble vitamins (vitamin A, D, E and K) around the body and ensures they are absorbed in the body so that they can do their jobs which include keeping cells functioning and supporting the immune system.
- It helps us enjoy food: Fat in food plays a key role in determining its taste and texture, and subsequently affects the food’s acceptability. Without fat, the smooth texture of a salad dressing is lost, while ice cream or chocolate lose their creamy mouth feel. Because taste is the number one reason why we eat certain foods, adding a small amount of fat to a stir-fry or salad will boost the flavour.
- Some are essential: Some fats such as omega-3 fats and omega-6 fats are considered essential, as the body cannot make them and we need to get them through food. Essential fatty acids are important for a number of bodily processes including brain function, growth and development.
- Replace unhealthy fats such as saturated fat and trans fats with healthy fats such as monounsaturated and polyunsaturated fats.
- Don’t overdo it as all fats contain the same number of kilojoules. Make sure you enjoy portion-controlled servings.
- Include oily fish such as tuna a couple of times per week.
- Snack on nuts and seeds.
- Cook with plant-based oils or drizzle them over salads.
- If you need to lose weight, cut back on the total amount of kilojoules you eat rather than focusing solely on the amount of fat.
Are you able to maintain your weight by including small amounts of healthy fats?