FATS,

which should make up no more than 30% of our total daily kilojoules, are the most concentrated source of kilojoules - double that of carbohydrates or protein. Depending on their chemical structure they may be termed saturated, polyunsaturated or monounsaturated. The less saturated oils, including those containing essential fatty acids such as those present in fish oils, have been found to provide better protection against heart disease.

CHOLESTEROL

WHAT IT IS

A white waxy substance natural in the human body and the body's requirements can be naturally produced by the liver. Fats in the diet, unsaturated as well as saturated, affect cholesterol levels even more than the cholesterol we consume.

WHERE IT IS

Excess cholesterol can build up in arteries causing atherosclerosis that in turn heightens the risk of stroke, heart attack, blindness, kidney failure, impotence and normal circulation of the blood. Cholesterol in food is only  found in food from an animal origin, never from plants.

WHY IT IS

Cholesterol is essential for life and is part of all cells.

AND WHEN IT IS – OK

A blood cholesterol reading of 4.2-5.4mmol/litre is considered average. Below this is considered low risk, above is high or very high, depending on the reading.

HOW TO MODERATE CHOLESTEROL IN YOUR DIET

Monitor your total fat intake from all sources, not just animal products - 20-30% of total calories is thought to be a safer intake than the national average of 40%. Where possible use monosaturated fats such as canola or olive oils, avocados, seeds or nuts, and oily fish. Limit cholesterol to around 300mg daily.
Maintain healthy weight.
Exercise regularly.
Consume the recommended amount of fibre, preferably from a variety of sources.
Drink plenty of water.

LOWER FAT EATING

In recent years, with the increased interest in and concern about our health, the eating public have been bombarded with a new language. The scientific jargon used to describe the fats we eat and their effect on our body, rather than enlighten us, has often just confused us more, resulting in some strange misunderstandings. We have all seen avocados with 'Cholesterol Free' stickers on them. Are they different to their un-stickered mates in the fruit market? Of course not. All avocadoes, because they are from a plant origin are free of cholesterol. Yet some fruits or vegetables have saturated fat, some are unsaturated and still others are monosaturated. Confused? It's no wonder. Let's try to demystify the vocabulary.

DEFINITION OF TERMS

Saturated fats are fats that are solid at room temperature and generally come from an animal source. Here we have  butter, lard, suet and dripping. Be careful though. Cream is saturated, but because it also contains milk (read the label – it may be 35%, 40% or even 48% fat) it remains liquid. Coconut oil is interesting, as even though it is from a plant source, it still hardens at room temperature e.g. copha. Palm oil, widely used in the manufacture of confectionery, cakes and biscuits is also saturated.

Monosaturated fats are preferable because they help the body to deal with cholesterol obtained from other foods. Three of the most importantly commonly available monosaturated  oils are those found in avocados, canola and olives. Tests and research carried out on people from Mediterranean countries, for instance point to the fact that the use of monosaturated oils actually reduces the amount of cholesterol in the blood. It is believed that the increased HDL's are able to clean excess cholesterol from the blood vessels and keep the body at a healthy equilibrium.

Polyunsaturated fats are found in most nut, seed and vegetable oils. Traditionally they have been used either in combination or with dairy foods to make margarine and cooking oils.  It was originally believed that this would be a preferable and healthier alternative to butter and other saturated fats, but recent studies now suggest that this was often a misguided belief. The very process necessary to make margarine – that of beating the oil – actually saturated it. We can see how saturated margarine is by its relative firmness at room temperature.

Cholesterol is a fatty substance made in the body by all animals, including humans and is essential to the health of the body. The problem comes when our intake overtakes our needs.  The first and most visible effect is that we will become obese and our bodies may then convert fat into blood cholesterol. It is then likely that deposits will form in our arteries, building up over a period of time like clogged drains. Eating large amounts of cholesterol will not raise our blood cholesterol levels if we are healthy, but because we are consuming more energy (kilojoules) than our body needs, we may put on weight. Cholesterol can also be raised by the consumption of cholesterol-free saturated fats.

There are five types of cholesterol present in the body, the most important being HDL's and LDL's. Current medical opinion believes that the ratio of these two is more important than cholesterol levels.

• LDL stands for low-density lipo-protein cholesterol and is believed to be the factor that correlates with heart disease and fatty build-ups on artery walls.

• HDL stands for high-density lipo-protein cholesterol, believed to actually aid the body is clearing excess cholesterol from the arteries.

WHICH FATS AND WHY AND WHEN?

Fats and oils provide more kilojoules gram for gram than any other food. Simple arithmetic immediately shows us that while we may be getting a terrific energy package, the nutritional backup is out of balance. Fats and oils do contain vitamins A and D, but other foods also provide vitamin A, and sunlight helps us make our own  vitamin D.
Oils are 100% fat, but butter and margarine, because they contain milk or water are around 80% fat. For example, when substituting oil for butter use approximately 1/3 - 1/5 less.
People in many affluent Western cultures find that over 50% of their energy intake is supplied by fats. This is very high and can cause the exclusion of other more important foods from the diet. Fats give a sense of satisfaction – they fill us up ­– and may cause us to eat less of other bulkier, more nutrient-rich foods. Nutritionists and physicians are suggesting that no more than 30% of energy should be supplied by fat and that 15-20% may be even more beneficial.

STRATEGIES FOR SUBSTITUTING FATS IN THE DIET

Spreads:

Look for the lowest fat spread you enjoy and use it. Butter and margarine have 4g of fat in every teaspoon. Light cream cheese has .8g. Natural yoghurt, jam, tomato sauce and chutney have even less. Avocado is a high fat fruit but its monosaturated benefits make it worth considering – half a medium one (135g) has 20g fat or equal to 5 teaspoons of butter, but without the cholesterol.

Frying:

Oil is 100% fat, but you can reduce the amount you use or omit it entirely by using non-stick pans. Cook with half water-half oil to retain some of the flavour and  browning, crisping effects of oil, but to halve the amount of fat. As the food cooks the liquid evaporates and the remaining oil continues to fry the food. You could substitute wine or fruit juice for water for a different flavour, or poach food entirely in liquid. If frying in oil, cook at the correct temperature so that the food does not soak up excess oil and when cooked, drain thoroughly on kitchen paper or paper towels. Olive or canola oils, because they are monosaturated, are preferable to saturated ones.

Food preparation:

Trim fat from all meat, skin chicken and fish, (although the Omega 3 fatty acids in most fish are beneficial).  Be aware of the fat that is present within meat as well as around the cuts. Well-marbled meat may be superior in flavour but it is heavier in cholesterol. Ask for lean cuts.

Shopping:

Manufacturers are becoming more aware of consumer's needs and preferences. It is now possible to buy reduced fat cheese in the block, or sliced and grated. There are low-fat yoghurts, sour cream, ricotta and cream cheese and many processed meats and bakery items that bear the label 'Fat Reduced' or others such as '95% fat-free'. Check carefully. Some may be as misleading as the 'Cholesterol Free' avocado stickers. Some foods may be 95% fat free in any case, but because of the relatively large amount needed to make up a serving, you are bound to consume a large amount of fat grams.

LOW FAT SAUCES

It is so easy to add many grams of fat (and of course hundreds of kilojoules) with sauces. Here are a few that won't break the daily fat budget:

• No-fat mayonnaise or dressings - look for them in the supermarket
• Tomato sauce
• Chutneys
• Chopped herbs mixed with skim yoghurt
• Onions 'sauteed' in water or low-fat stock, then pureed
• Cooked and pureed carrots or pumpkin, seasoned with herbs or curryCooked apple, pureed and seasoned with lemon juice and cinnamon
• Pureed mango or pawpaw with coriander
• Salsas made by combining fresh fruit, onion, herbs and seasoning
• Skim ricotta or cottage cheese pureed with herbs and cooked vegetable or fruits
• Mashed avocado and yoghurt, seasoned with chilli and coriander
• Watercress pureed with a little consomme or juice
• V8 juice thickened with cornflour.