Food
Fat quiz
Introduction
How much saturated fat do you eat? Take our quiz to find out!
The fat quiz will help you work out if you are eating too much saturated fat. We also tell you what you need to know about the different types of fats, and how to cut down the amount of saturated fat in your diet.
Overview
Gram for gram, fat contributes more kilojoules than protein or carbohydrate, so cutting back on it is a good start to reducing excess kilojoules. However, if you're still eating more kilojoules than you burn - it inevitably leads to unused energy that makes you gain weight.
And yet there's more to reducing fats in your diet than losing weight - the type of fat you eat is also important. The NZ Food and Nutrition Guidelines state people should "prepare foods or choose pre-prepared foods, drinks and snacks with minimal added fat, especially saturated fat".
So, your emphasis should be on limiting saturated fat. Reducing your overall fat intake is second priority.
Fat facts
While cutting kilojoules is important in losing weight, where your heart and arteries are concerned it's the type of fat you eat that matters most.
Essentially, it's all about the effect that the different kinds of fat have on fats in the blood, including blood cholesterol. An area where many nutrition experts agree is that an increase in saturated fat in the diet is associated with an increase in coronary heart disease, and also increases in some other problems, including type 2 diabetes.
Because foods high in saturated fats are mostly high in kilojoules as well, restricting their intake will reduce the overall amount of kilojoules you consume. Some studies also show that by cutting back on saturated fat, total dietary fat tends also to be reduced.
Cholesterol
Cholesterol is necessary for essential functions, such as making sex hormones and vitamin D. The body makes most of what it needs, but sometimes excessive amounts are produced, if too much saturated fat is consumed.
There is only one type of blood cholesterol, but it's attached to different carriers called lipoproteins. The main ones are known as high-density lipoprotein (HDL) and low-density lipoprotein (LDL). HDL is the "good" form, as it transports excess cholesterol from the artery walls to the liver. "Bad" LDL cholesterol gets dumped in your artery walls, helping to clog them and restricting blood flow.
Animal products contain dietary cholesterol, so most people do eat some in their diet. However, while this cholesterol can increase LDL cholesterol, it contributes much less to the body's cholesterol than saturated or trans fat.
Fat
As for fat, it can be divided into two major types: saturated, and unsaturated (monounsaturated and polyunsaturated), which are differentiated by their chemical make-up. Most foods contain various combinations of these types of fat.
Saturated fat
Saturated fat is primarily responsible for raising "bad" LDL cholesterol levels in the blood, which ultimately lead to blocked arteries. It's found in high quantities in fatty meats and dairy foods, though it's also in some vegetable oils (palm and coconut oils).
Because saturated fats are convenient (they're solid at room temperature) and relatively cheap, they're used a lot in commercially produced foods such as cakes, biscuits, pastries and chocolate bars, as well as fried takeaway foods and potato crisps. It's mandatory for the saturated fat content to be specified in the nutrition information panel on packaged foods, but unfortunately not restaurant or takeaway meals.
Polyunsaturated fats
Polyunsaturated fats are "good" fats that have been found to lower artery-clogging LDL cholesterol.
There are two forms.
- Omega-6 fats are found in sunflower, safflower, sesame, corn and soybean oils and seeds.
- Omega-3 fats are found in high quantities in seafood, especially fish such as swordfish, salmon, gemfish, tuna and sardines, while other types of omega 3 are found in plant sources such as flaxseed, walnuts, soybeans and green vegetables.
Monounsaturated fat
Monounsaturated fat is also regarded as a "good" fat. It too can lower LDL cholesterol levels, but not quite to the extent that polyunsaturated fat does. It's found in large quantities in canola and olive oil, avocados and nuts.
So replacing saturated fat with a mixture of omega-3 and omega-6 polyunsaturated fats as well as some monounsaturated fat is the game plan for a healthy heart. Depending on the total amount you eat, it may also help you lose weight.
Trans fats
Trans fats are another type of unsaturated fat, but instead of being good for you like other unsaturated fats, trans fats (formed when vegetable oils are hydrogenated) act like saturated fat in the body - raising the level of LDL cholesterol and reducing levels of HDL.
The problematic trans fats are mainly generated when hydrogen is added to mono- or polyunsaturated fats. Partially hydrogenating them like this hardens them, making them more convenient to use on a commercial scale, and like most saturated fats they're also cheap. So in our diet we mainly get trans fat from vegetable shortening and commercial frying fat, used mostly in the food industry in the production of cakes, biscuits and other processed foods, and in takeaway meals.
Table spreads were also once a main offender, with a high trans fat content, but manufacturers have made a concerted effort to reduce levels, and these days most spreads have low levels.
Where's trans fat on the label?
So, if it's mandatory to label the amount of saturated fat in foods, and trans fats act just like saturated fat in the body, why aren't they listed in the nutrition panel?
Under the current Food Standards Code, only total fat and saturated fat need to be labelled unless there's a claim made on the packaging about mono, poly or trans fats, in which case they must then be labelled.
Under Department of Food and Drug Administration regulations in the United States, the labelling of trans fat became mandatory in 2006.
Unfortunately even if this is eventually accepted here, takeaway and restaurant meals are excluded from nutrition labelling laws, and they're a primary source of trans fats in the diet. But at least packaged foods such as cakes, chocolate, biscuits and frozen meals would be required to disclose the amount of trans fat in them, giving you a better idea how much 'bad' fat overall you're eating. Perhaps it might even be an incentive for manufacturers to reduce the amount their products contain.
For now, you'll have to rely on checking the ingredient list for ingredients such as hydrogenated or partially hydrogenated vegetable oil - but it's still no guarantee.
How to cut the sat fat
Here's some tips on how you can lower the saturated fat in your diet:
- Only occasionally eat biscuits, cakes, pastries, snack foods (including chocolate) and fried take-away foods.
- Use a small amount of a monosaturated or polyunsaturated table spread instead of butter. Try avocado, hummus or low-fat mayonnaise as a tasty spread.
- Replace full-fat dairy products with reduced or low-fat versions.
- Replace fatty cuts of meat with lean cuts, and only occasionally eat sausages, salami, bacon, other smallgoods, devon and other luncheon meats.
- Use mono and polyunsaturated oils in your cooking (see Fat facts for examples).
- Have tomato and vegetable-based pasta and rice sauces instead of cream ones. Use trim milk or evaporated trim milk instead of cream, and low-fat yoghurt instead of sour cream.
- Grill or shallow-fry foods in poly or monounsaturated oils rather than deep-frying or roasting in fat.
- Add low-fat natural yoghurt, ricotta cheese, a little olive oil or table spread to vegies instead of butter or cheese sauce.
- Eat more unsalted nuts, such as almonds, walnuts and pecans - they're high in unsaturated fat, and are also a good source of fibre. But remember, nuts are high in total fat.