Our love affair with low-fat products could actually be doing us more harm than good. Bronwen King has the skinny on why.
Back in 2011, Denmark introduced a ‘fat tax’ on all foods containing more than 2.3 per cent saturated fat, and many said it was such a good idea that other countries would surely follow suit.
Yet, the Danish government recently abolished the tax. The move, they said, was financially motivated. But it has also become apparent the foods we’re eating in place of some of these ‘fatty foods’ may be doing us more harm than good. While some low-fat foods are useful for health and weight management (low-fat milk for example) many ‘light’ or ‘diet’ products are not necessarily lower in kilojoules. This means they could actually encourage weight gain rather than weight loss.
What replaces fat in food?
Let’s be honest, fat tastes good! It gives our food a luscious flavour and has a creamy, velvety mouth feel. When added into cooking, it can also provide a delicious crispness. So any replacement needs to have a similar effect, but with less fat and therefore fewer kilojoules.
Unfortunately, you’ll often find low-fat products have more carbohydrates and sugar and therefore almost the same number of kilojoules as the full fat products they’re replacing.
That’s because mimicking the properties of fat often requires a complex mix of replacements.
In reduced fat sweet foods, such as biscuits and cakes, fat is often replaced with sugars (dextrins, maltodextrins and sometimes corn syrup), along with modified starch and vegetable gums.
In low-fat dairy products, to get that lovely feeling of creaminess often means adding skim milk powder and vegetable gums. These increase the protein content of the product, which can help with satiety, and that is a positive. The issue is that extra sugar can sometimes be added to compensate for flavour. This is common in reduced-fat frozen desserts, fruit-flavoured yoghurts and ice-creams.
Adding sugars and modified starches to a food gives it a higher Glycaemic Index (GI). This means you may feel hungrier sooner after eating these reduced-fat products because they are digested faster. So, in the end you could eat more than you would have with a lower-GI food. Many reduced-fat sweet foods (whether it’s a cake, yoghurt or ice-cream) therefore aren’t likely to help when it comes to managing your weight.
In addition, they can reinforce a sweet food habit as your taste buds become accustomed to sweeter flavours, drawing you towards these foods more often, which also works against any weight loss efforts.
In savoury products, fat (particularly saturated fat from butter), is often replaced with vegetable oils, emulsifiers, vegetable gums and whey protein. Often the vegetable oils have been altered to be hard at room temperature to act more like butter. Using these means a product could be higher in unhealthy trans fats, which can raise your cholesterol levels.
How are we fooled?
Author Brian Wansink, in his book Mindless eating, why we eat more than we think (Random House), describes studies which show people assume low-fat versions of foods are also lower in kilojoules.
So, when people were given foods marked as low-fat they ate around 25–44 per cent more than when foods were marked as regular fat. He estimates people perceive low-fat foods to have around 44 per cent less kilojoules than regular foods, but the reality is more like 11 per cent. He found when people chose low-fat products they felt virtuous. This ‘halo’ effect meant they were more likely to supersize their portions through a sense of ‘guilt-free’ entitlement.
Fat has the highest number of kilojoules per gram, compared to any other part of food. This is partly why, in the past, we’ve been encouraged to eat less fat to control our weight. But fat is actually essential in our diets – it’s the type of fat you need to worry about. Health experts are realising by extolling low-fat diets, people have misguidedly been dropping all fats, including the ‘good’, unsaturated fats as well.
“We need some fat in our diets because it comes packaged with fat-soluble nutrients – namely vitamins A, D, E and K,” explains nutritionist Amanda Ursell. “It’s also a valuable source of energy and provides the essential fatty acids our bodies can’t make on their own,” she adds.
A little fat helps our bodies absorb the antioxidants found in tomatoes, carrots and green leafy vegies, studies show.
Nuts, which are actually high in fat, can play an important role in prevention of long-term weight gain, evidence shows. And as part of a healthy, energy-controlled diet, they may even increase chances of weight loss.
It’s the type of fat that determines whether a food is a positive addition to your diet. Saturated and trans fats are the ones to avoid, as they tend to raise cholesterol levels, which can be especially harmful when it comes to heart health. Saturated fats are mainly found in animal products such as butter, cream, cheese, meat fat and also in processed foods that use these as ingredients (eg. biscuits, cakes and pastries). It’s also found in coconut and palm oil, which are often used in takeaway and some packaged foods.
Unsaturated fats are the ones we want to keep in our diet as they tend to lower total cholesterol and increase HDL or ‘good’ cholesterol levels, making them a positive choice for a healthy heart. Unsaturated fats are mostly found in plant foods such as olives, olive oil, canola oil, sunflower oil, safflower oil, avocados and nuts, along with oily fish – notably sardines, salmon, tuna and mackarel.
Re-evaluate your choices next time you’re making up your shopping list. Look closely at food labels on the reduced-fat products you buy. It’s better to choose foods with unsaturated fats over many of the heavily-hyped up ‘diet’ or ‘lite’ alternatives.
Ursell says most importantly “a diet that includes some fat is more likely to succeed in the long-term, because it’s more interesting and pleasurable than a very low-fat existence.”
How to get the right fat
1. Remember we do need fat in our diet. Less is not necessarily best as long as the fats you’re eating are the ‘heart-healthy’ kinds, found in vegetable oils, nuts, avocados and oily fish. Fat is needed as a backup energy supply, for production of hormones, to carry fat soluble vitamins, as a structural component of cell membranes and for insulation and protection of vital organs.
2. Read labels and compare products by using the per 100g column on the pack. Go for the variety with the least amount of saturated fat, but also consider kilojoules. If the lower fat product is not also significantly lower in kilojoules a red flag should be raised.
3. Be wary of low-fat sweet foods. Biscuits, cakes, sauces, ice-creams, fruit yoghurts and other frozen desserts marketed as low-fat are likely to be higher in sugar and other carbohydrates and not necessarily lower in kilojoules.
4. Always use low-fat replacements quantity for quantity. Resist the urge to supersize or your efforts will be in vain.
5. Remember there’s no magic formula for weight loss. The best advice is to watch your portion sizes and to include lean protein, nuts, seeds, fruits, vegetables, legumes and carbohydrates in the form of unprocessed grains. These can all aid satiety, helping you feel full for longer.
Useful low-fat products
Your top five low-fat products – make the swap now for your health!
1. Low-fat milk
Over a week, the amount of milk we drink (from tea, coffee, cereal etc) can really add up. So train your palate to make the swap - it’s saturated fat you’ll be trimming.
2. Low-fat crackers
As a guide, look for high-fibre crackers that are low in fat (under 3g fat per 100g). Enjoy the yummy, grainy flavour.
3. Low-fat or ‘light’ cream cheese and sour cream
Some varieties have as little as 5g fat per 100g (compared to 30–35g fat for regular versions), so you can save a huge 800kJ and 17g of saturated fat.
4. Low-fat unsweetened yoghurt
Plain, low-fat yoghurt whips its fruit-flavoured cousins as it’s not sweetened, it’s simply the regular version with the fat trimmed down. If you’re a sweet-tooth at heart, then check the label to make sure your fruit yoghurt isn’t boosted with extra sugar.
5. Reduced-fat cheese
It tastes pretty much the same, so what’s to lose? Plenty of fat – reduced-fat cheese has around 25g fat per 100g compared to regular tasty cheese which has 34–35 per cent fat. If you do feel it lacks flavour, add a little grated parmesan which, although higher in fat, has a stronger flavour so you don’t need to use as much.
Low-fat to watch or minimise
Be careful with these low-fat versions – they all make up for fat in other ways.
1. Ready-to-go Asian or Italian sauces
Chances are, if the fat has been reduced then sugars and starches have been added to thicken and give flavour. Again, compare labels for sugar and kilojoules.
2. Peanut butter
You can’t lower the fat in peanut butter without removing the key ingredient, peanuts. For this reason, lower fat varieties are not significantly lower in kilojoules. Also extra sugars and starches are added to compensate for flavour. Choose a regular version with no added sugar or salt.
3. Ice-creams and frozen desserts
These are likely to be high in sugar so should be treated the same as their higher fat counterparts – as occasional foods only.
4. Mayonnaise and salad dressings
Low-fat varieties tend to have sugars and starches added to flavour and to thicken. So check the label for kilojoules and carbohydrates per 100g – if significantly lower, it could be a good replacement.
5. Cereals and muesli bars
Low-fat versions often have a higher GI and an equal number of kilojoules due to added sugar or honey. Compare labels. If the sugar comes from dried fruit, it’s not such a problem. Cereals like wheat biscuits and oats are your best choices.
How much fat is too much?
Remember, it’s not just the quantity, it’s the quality of fats that count. Generally, it is recommended that we eat a total of 70g of fat in our diet per day. By the same token, we should limit the unhealthy, saturated fat we eat to no more than 24g per day.