The idea of a low-fat diet spread from America in the early 80s. Studies found that the less fat you ate, the lower your cholesterol levels and the lower your risk of heart disease. It was also assumed that a high fat diet lead to being overweight. Were those studies correct or flawed? Do we even need to revisit the studies when you just have to look around you to see the evidence?
So which fats are good fats, and which are the bad guys? And are there ugly ones too? Yes, and it gets even more confusing as good fats turn ugly, and the bad ones aren’t so bad after all…
Unsaturated fats, found in vegetable oils are widely considered as the good guys. Which is correct, to a point, but there are some issues. Here’s why:
There are two types of unsaturated fat. On an atomic level, it’s all to do with how many double bonds there are in the fatty acid chain, mono (meaning one) and poly (meaning many).
Poly-unsaturated fats are unstable and go rancid easily. Free radicals in the rancid oils have been shown to contribute towards premature aging, increase of heart disease and cancer and damage of organs.
Poly-unsats can be further divided into omega 6 and omega 3 oils, again classified according to how many double bonds there are. Most commercial vegetable oils contain high levels of omega 6 compared to omega 3, which is unfavourable (it should be equal, and poly-unsats should make up no more than 4% of your total calorie intake). High levels of omega 6 in the diet have been linked to increased tendency to form blood clots, high blood pressure, weight gain, inflammation and more.
Mono-unsaturated fats, such as olive and avocado are more stable and don’t go rancid as quickly. Extra virgin oils are pressed at low temperatures without exposure to damaging oxygen and light.
And then, in the making of margarine and spreads, when unsaturated fats are super-heated and hydrogenised, they turn into trans-fats. These are the ugly fats, which are toxic and to be avoided at all costs.
What about saturated fats, aren’t they the bad guys?
Nope, saturated fats, such as those found in lard, dripping, goose fat and butter aren’t the cause of many of our modern diseases. They play a vital role in bone health, protect the liver from alcohol and other toxins, enhance the immune system, lower Lp(a), which is a substance found in the blood that indicates the likelihood of heart disease, and are needed to help retain the benefits of omega 3s, amongst other virtues.
So what fats should I use in my cooking?
Butter is actually less likely to cause weight gain than olive oil or other commercial vegetable oils as it is directly absorbed for quick energy. This is due to its’ short-chain fatty acids, which are antimicrobial (helping maintain good bacteria in the digestive system), antitumoral and supportive to the immune system.
Extra virgin olive oil is great for pouring over salads, making up dressings, and cooking at moderate temperatures. It is rich in antioxidants, but don’t overdo it, as it’s longer chain fatty acids are more likely to contribute to fat build up.
Animal fats such as lard, beef dripping and goose fat are stable, useful for frying and bring lots of flavour. If you haven’t tried roasting potatoes in goose fat, I highly recommend it, they’re delicious! Some researchers suggest pork products may contribute towards cancer, others say that it is only the meat that does this, not the fat. Pork is a good source of vitamin D however, so I’ll leave that decision to you.
According to Dr Mercola (www.mercola.com), where I did most of my research about this article, all the following oils should be avoided; safflower (borage), corn, sunflower, soybean and rapeseed, as they contain too much omega 6 compared to omega 3. You are much better off eating the raw, fresh seeds, such as sunflower seeds, than using the commercially produced oils.
Flax seed oil has a much better omega 3 to omega 6 ratio, so is valuable when poured over salads but should never be heated.
Coconut oil has strong antifungal and antimicrobial properties and doesn’t contribute towards heart disease. It is very stable and can be used in baking.
We did as we were told, we reduced our fat intake, but obesity has increased and continues to do so. Why? Find out in the next article, when I’ll explain about the different types of sugar.
