Good fats, bad fats and old chestnuts

While it’s true that we need some fats in our food, the type and the quantity are the most important factors

Jack Rogers of Newgrange Gold, one of Ireland’s largest seed oil producers, with last summer’s crop of rapeseed

Jack Rogers of Newgrange Gold, one of Ireland’s largest seed oil producers, with last summer’s crop of rapeseed


There is a lot of confusion about the various fats out there and how much we need. It now seems clear that even certain fat types like “saturated fat” may have different health effects depending on the food source. For example a recent study in the American Journal of Clinical Nutrition found that a higher intake of meat saturated fat was associated with greater cardiovascular disease (CVD) risk, whereas a higher intake of dairy saturated fat was associated with lower CVD risk.

One thing is certain, however – we all need some dietary fat. Fat is essential for helping the body to absorb and transport fat soluble vitamins. It supplies us with essential fatty acids that the body can’t make. Fat is also a structural component of the brain, supplies energy for body cells, produces hormones and protects and cushions our internal organs.

It’s the quality (or type) and quantity of fat in our diet that’s important and the subject of on-going research.

Fat and weight gain
Fat, no matter what the type, contains twice the amount of calories as carbohydrate or protein, so it’s easy to eat a lot of calories in high-fat foods. It doesn’t provide the same satiety as protein. One gram of fat has 9kcals, and one gram of carbohydrate or protein has 4kcals. Alcohol provides 7kcals per gram.

Eating too many fats, or carbs or proteins means excess calories. Eating more calories than you burn increases your weight and susceptibility to other disease. Eating excessive amounts of trans fats, for example, increases your risk factors of CVD through inflammatory processes.

It is important to get the balance of your dietary fats right. This means replacing trans fats and certain saturated fats with healthier polyunsaturated (omega 3 and 6) and monounsaturated fats (omega 9).

Simply cutting out all saturated fats and replacing them with processed and refined carbohydrates, seems in fact, to be as bad if not worse, for health. This is the reason why low-fat diets seemed to be more harmful than healthful for many. Simply choosing refined carbohydrates to replace the lost calories from fat is not the right strategy.

Good Fats
Also called unsaturated fats, “good fats” are better for your heart than trans or certain saturated fats. Unsaturated fats usually come from vegetable or seafood sources and are divided into monounsaturated and polyunsaturated fats. These include foods such as olive oil; rapeseed oil; sunflower and sesame oils and spread made from these oils; walnuts; Brazil nuts; almonds; hazelnuts; avocados; sunflower seeds; sesame seeds; pumpkin seeds and chia seeds.

Omega 3 fatty acids are a type of polyunsaturated fat. They are a type of beneficial fat that can help lower triglycerides and help protect your heart and joints. Oily fish is the best natural source of omega 3 fatty acids. Types of oily fish include salmon, trout, mackerel, herring, sardines, kippers, fresh tuna. Fresh, frozen and tinned varieties can be enjoyed although the canning process can almost halve the omega 3 levels, so check the label. Aim to eat two portions of fish every week and try to make at least one of these oily.

Not-so-good fats
These fats are mostly found as hard fats that come from animal sources. Eating too many trans fats increases your risk of heart disease and stroke. Excessive amounts of saturated fats cause weight gain and are associated with certain types of cancers. Saturated fat is found in foods such as butter, lard, cream, full fat milk and yoghurts, cheese, processed meats, fat on meat, chocolate, biscuits, cakes, muffins, doughnuts, pastries, chips and takeaways.

Obviously, some of these foods offer a myriad of nutrients we need for bone and heart health such as milk, cheese and yoghurt, so the advice for children, adults, pregnant and breast feeding mums is to eat three servings of low-fat dairy every day. A serving is any of the following: one 125mg carton of low-fat probiotic yoghurt, one matchbox size of lower fat cheese (reduced fat cheddar, brie, camembert, feta, mozzarella, haloumi) or one 200ml glass of low-fat milk. Teenagers aged between nine and 18 need five servings to support rapid growth and bone development.

The old chestnut of what to spread on your slice of toast will depend on the rest of your diet and your balance of fats overall. You might enjoy a little butter containing primarily saturated fat as long as you don’t have a muffin at 11am and the sausage roll for lunch. But “treats and sweets” seem to be more than occasional foods for many of us, and it’s critical to look at the frequent choices we make to determine how that affects the overall picture. Daily habits of choosing lower-fat dairy can be useful as long as you don’t replace the calories with something worse.

There is a prevailing concern that a lower-fat version of a food must be high in sugar. Not necessarily true. Manufacturers do not add sugar to low-fat milk or reduced-fat cheddar. They just remove fat. Yoghurt on the other hand is different and you have to read the label of ingredients to see where the sugar comes from. The nutrition table will give you the total amount of sugar in the pot, but the ingredient list will help you understand the source of that sugar. Some of these might be natural sources. For example, sugar in yoghurts might come from the lactose naturally present in milk or from pureed or added fruit. On the other hand it could be added as sucrose or table sugar. You read and decide.


Many slimmers shy away from avocados, but calorie for calorie they offer a super array of nutrients, including potassium ,which helps to regulate blood pressure, the antioxidant vitamin E and healthy monounsaturated fat. Half an avocado is a portion and contains about 135 calories.

Nuts are high in calories and contain healthy monounsaturated fat, essential vitamins, minerals and fibre. Walnuts, flaxseeds and chai seeds are also good sources of omega 3 fatty acids. Studies suggest that eating a handful of nuts a few times a week helps reduce heart disease, satisfy cravings and help control weight – a small handful (about 30g) contains about 200kcals.

Olive oil’s
protective effects are due to two fundamental components: monounsaturated fatty acids and antioxidant substances. Each tablespoon provides about 120 calories.

Rapeseed oil is produced here in Ireland and is a fantastic less expensive alternative to extra virgin olive oil, with similar health benefits. Its higher heating temperature makes it ideal for cooking .

Coconut oil has been a staple in tropical regions of the world for thousands of years. Like all oils it is 100 per cent fat, but the type of plant fat it contains is unique – more than 85 per cent of the fat is saturated, but much of it is in the form of medium- chain fatty acids, which don’t appear to have the same adverse effects on health as other saturated fats.

A new oil on the shelves, Camelina, is grown, pressed and bottled on the Newgrange farm at Crewbane in Slane. Its nutritional profile of healthy unsaturated fat is often compared to linseed or flaxseed oil, but it has the added benefit of a higher vitamin E content and a longer shelf-life. Its taste is nutty in flavour and it has a high smoke point, making it another great choice for cooking and roasting if want an alternative to rapeseed oil .

Bananas are low-fat fruit, and though higher in calories than many other fruits, their calories come from carbohydrate – excellent for refuelling before, during and after exercise. They are also a rich source of potassium which helps regulate blood pressure and contain vitamin B6, important for healthy skin and hair, reducing fatigue and easing premenstrual symptoms.
Swap blended oils for olive, rapeseed, or Camelina oils.

Swap high-fat cheese and dairy for low-fat dairy products. Aim for three servings of low-fat dairy every day.

Swap refined carb crisps and snack packs for unsalted nuts and seeds. Limit your portion to a small handful.

Swap fried foods and takeaways for meals prepared at home with a healthy oil.

Swap sausages, burgers and fatty meats for lean meats, oily fish and pulses.

Replace certain hard fats in baking with coconut oil.

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