Fats

The good news? Not all fat is bad. In fact, fat is present in every single cell in your body, and we need it to function.

The bad news? Fat is easily stored by the body and storing too much of it can lead to serious health problems.

So, what are the different types of fat and how can you tell which are best avoided?

What does it do?

Fat is needed for all sorts of reasons…

Cells: cell membranes – the thin, outer covering around each and every cell – are made up of fat molecules and there are around 50 trillion cells in the human body, which is a lot of membranes.

Storage: fat is the most efficient way for our bodies to store energy. It provides more calories per gram than any other nutrient and can be stored in practically limitless amounts. Evolutionarily-speaking, this is a good thing but it has caused havoc since we no longer have to hunt-and-gather our lunch.

Metabolism: fat’s also involved in lots of body processes, such as helping to produce hormones and keeping the immune system ticking over. Vitamins A, D, E and K are known as the fat-soluble vitamins because they need fat in order to be absorbed by the body.

What are the types of fat?

Fat can be separated into two broad types – saturated and unsaturated. Within these, though, there are further divisions…

Saturated

Health campaigns have, for many years, warned people to cut their intake of saturated fat – by switching from whole to skimmed milk, for example. This is because saturated fat can increase the amount of cholesterol in the blood, which in turn can increase the risk of developing heart disease.

Saturated fats are usually found in foods from animal sources and are often easy to spot because they’re solid at room temperature. So, butter, cheese and the fat on meat contain saturated fat. There are exceptions - the fat in milk and yoghurt isn’t solid, but is saturated.

Unsaturated fats are further divided into ‘monounsaturated’ and ‘polyunsaturated’. They’re usually found in plant foods and are usually liquid at room temperature - vegetable oil, for example. Coconut is an exception to this rule because, although it’s a plant, it actually contains high amounts of saturated fat.

Monounsaturated

Found in the oils from olives, rapeseed, avocados and various types of nut, monounsaturated fats actually lower levels of cholesterol in the blood, which may help reduce the risk of heart disease. These types of fat are also a good source of vitamin E, which is an antioxidant helping to protect cells against the damaging effects of free radicals.

Polyunsaturated

These are found in walnuts, sunflower and pumpkin seeds and vegetable oils like sunflower, soybean and corn oil. They lower levels of cholesterol in your blood.

A particularly important polyunsaturated fat is known as omega 3. Oily fish such as salmon, mackerel, herring and trout are especially good sources of omega 3, which plays a crucial role in brain function and in the normal growth and development of your body. Most people in this country don’t eat enough omega 3-containing foods.

Trans fats

This final group of fats is less well-known but should be avoided. Trans fats are produced when vegetable oil undergoes a process which turns the liquid oil into solid fat. The result is known as hydrogenated or partially hydrogenated vegetable oil. It's often used in the production of biscuits, cakes, pastry, margarine and other processed and ‘fast’ foods. In beef, lamb and dairy products, trans fats occur naturally, at extremely low levels.

This type of fat has no known nutritional benefits – worse still, there is evidence to suggest that its effects are worse than those of saturated fats, by raising the levels of ‘bad’ cholesterol and reducing the levels of ‘good’ cholesterol, increasing the risk of heart disease.

Asda has removed hydrogenated vegetable oil (HVO) from all its own-brand products but many processed foods still contain it. If HVO is listed in the ingredients then the product probably contains trans fats.

What about weight?

Putting on weight is all about consuming more calories than you use up. As well as increasing the amount of physical activity that you do, you need to reduce your intake of calories.

Cutting out fat completely would be disastrous to your health but cutting back is important – and so is changing the type of fats that you eat, for the better.

Try these tips to get the balance right:

Swap whole milk for skimmed or semi-skimmed

Choose a low-fat spread instead of butter

Cut off any visible fat from meat and choose lean cuts whenever possible

Poach eggs instead of frying

Mix rapeseed oil or olive oil with wine or cider vinegar for a healthy salad dressing instead of creamy dressings

Spread sandwiches with soft avocado instead of mayonnaise

Go for oven chips instead of chip shop or deep-fried chips at home

Snack on plain almonds instead of crisps, dried fruit instead of chocolate

Check packs and choose foods that don’t contain hydrogenated vegetable oil

Try tinned sardines in tomato sauce – they’re great on toast