Fat - Friends or Foe?

By Community Correspondent Dr. Natasha Mistry

“The doctor said….

…my blood cholesterol was high… …my blood lipids were abnormal… …I need to eat less saturated fat…

We’ve all heard these wise words from our doctors before, but sometimes it’s all Greek to us. What does the doctor mean when he says such things? How does the food that I eat relate to these “blood lipids”?

Well as the lovely Sister Maria once sang – let’s start at the very beginning, it’s a very good place to start.

What exactly are lipids?

Lipids are basically fats – insoluble in water. They include fats and oils (triglycerides) and cholesterol that we consume.

Contrary to popular belief, fat will not kill you. Too much fat will. You need some fat to survive – our brain wouldn’t function, we’d all have dry cracked skin, every time we rode our bikes or horses we get serious internal injuries, we’d be cold and miserable. We need fat to provide us with energy (its 9 kcal per gram compared to only 4 kcal per gram of carbohydrate or protein). Other than energy it insulates us, provides our internal organs with padding, gives our muscles energy and helps keep our cells looking healthy. We also need fats for the absorption of fat soluble vitamins i.e. vitamin A, D, E, K – without any fats in our diet, we would definitely be deficient in these.

But fat also has other relatively important functions. Anyone who has been on a low-fat or no-fat diet knows how dull and boring it can be. Fats make food smell good – all the chemicals that give food that lovely aroma – are all fat soluble…thinking of garlic butter or spices roasting for a curry or sautéing onions. And because they help release all those lovely aromas – they help stimulate your appetite, getting your juices going (literally) for the meal. Fat also lends texture to food – making it either crispy (think chips) or smooth (think a nice white sauce over your fish) or moist and juicy (think keeping the skin on chicken when roasting). But more importantly – once you’ve eaten the lovely aromatic appetising meal – fat helps send signals to your brain telling it that you’re full up. That’s a really important function – Satiety. This is why often people who are on a low-fat or no-fat diet – report feeling unsatisfied after a meal - which begins a vicious cycle of craving snacks.

What kinds of fats are there?

We know fat is important and essential. But there are different kinds of fats – we’ve all heard about the “good” fats and “bad” fats. I don’t want this to be a dull lecture in biochemistry – but here’s a handy way of remembering which ones to eat.

Harder the fat the more saturated it is. Its these saturated fats that increase your risk of getting fatty deposits in your arteries (Artherosclerosis) and various other complications of heart disease. So lard, beef fat, pork rind, lamb fat are all saturated fats and as a rule you want to restrict their intake. Often people (chefs in particular!) complain that food loses its flavour if you remove the fat (okay, see above) but if you are at risk of heart disease – you can compromise. Cook the chop or steak with the fat on – and trim it off and throw it away before serving – that way you’re not tempted to nibble on it if it’s on your plate. Chicken skin is less saturated and therefore appears somewhat softer - but still needs to be limited. Roast your chicken with its skin on, just slice it off when serving.

You then move down the hardness scale – from visible fats on meats to butter, margarine and oils. These are all rich in polyunsaturated fat (PUFA) and monounsaturated fat (MUFA) – often known as the “good fats”. You would generally use PUFAs in cooking – sunflower, safflower, vegetable oils. MUFAs you will find in olive oil, canola and peanut oil. Its also found in most nuts and seeds, avocadoes, peanut butter and seasame seeds. You can use these to cook or make salad dressings. But as with all fat rich foods – you want to make sure you watch your amounts.

So what’s all this about omega 3?

Omega 3 is a kind of PUFA – the only difference is that we most definitely need it in our diet because our body does not produce any of it. In particular, EPA and DHA (Eicosapentanoic Acid and Docosahexanoic Acid for those who are interested) are essential to the body and are found mainly in fish oils. These fatty acids are also essential for normal brain growth and development in infants and children.

Fish oils gained importance particularly with regard to heart health, when they discovered that natives of Greenland, Alaska and Canada (Eskimos) had a lower incidence of heart disease (including lower blood pressure and heart rates and fewer blood clots) when compared with their warmer counterparts. They attributed this to their high consumption of oily fish (salmon, mackerel, fresh tuna, and sardines) and other marine life (krill).

So how much omega 3 shall I eat?

To get the cardio-protective benefits of omega 3 – the Food Standards Agency (UK) recommends that we consume at least 2-4 portions of fish a week, at least one of which should be oily.

• Girls and women who are considering getting pregnant, are pregnant or breastfeeding – 2 portions a week • All other women, men and boys – up to 4 portions a week

So what’s an oily/fatty fish

Remember the name refers to the oil naturally present in the fish (esp. skin) and not the oil that you cook it in!! 140 grams is an average portion.

Any from this list of oily fish

Mackerel, Salmon, Kippers, Herring, Trout and Sardines. Salmon Pilchards, Kipper, Eel, Whitebait, Tuna (fresh only), Anchovies, Swordfish, Bloater, Cacha, Carp, Hilsa, Jack fish, Orange roughy, Sprats

Any of these white fish are also good for you, but have less OMEGA 3 content.

Cod Haddock Plaice Coley Whiting Lemon sole Skate Halibut Rock salmon/Dogfish Catfish Dover sole Flounder Flying fish Hake Hoki John Dory Monkfish Pollack Pomfret Red and grey mullet Red fish Red snapper Rohu Sea bass Sea bream Shark Tilapia Turbot Tinned tuna Marlin

What if I don’t eat fish?

You can also get Omega 3 from rapeseed oil, walnuts, and peanuts. Grass fed animals e.g.: Beef can also have some omega 3 content. Chickens fed with an omega 3 rich feed also produce omega 3 rich eggs. Fortified foods are also an option (more on these in a later article). But these can be a bit expensive.

The next few articles will cover Hydrogenated and Trans Fats, Cholesterol and Fish oil supplements.