Fat has had such bad press over the years that many people are left confused. Is it good for us? Is it bad for us? Will it lead to high cholesterol? Clogged arteries?
What if I told you that fat can help you lose weight, protect against heart disease, support hormone balance, absorb vitamins and boost your immune system. Surprised?
The key lies in knowing which fats to eat and which to avoid. Some fats are definitely better than others. Let’s take a closer look…
What are the different fats and what do they do? Fats to include in your diet are:
Saturated fat
These are the fats that traditionally have the worst reputation, found in animal fats and coconut oil.
However, the information we’ve been given for decades demonising saturated fats has been proved wrong. We now understand that dietary saturated fats don’t raise cholesterol. They are not fats that we need to avoid.
Does that mean that you should enjoy meat and butter for breakfast, lunch and dinner? No. But including them in your diet on a regular basis is unlikely to do you any harm.
Monounsaturated fats
Monounsaturated fats are those associated with the heart-healthy, anti-inflammatory Mediterranean diet. Populations that eat a lot of these fats have some of the lowest rates of heart disease in the world.
Many cardiologists advocate the Mediterranean diet. Studies link higher intakes of monounsaturated fats (plus a real emphasis on brightly coloured vegetables, whole grains and fish) to lower cholesterol or, to be more accurate, a better ratio of LDL to HDL cholesterol.
Polyunsaturated fats
You will probably know these as omega-3 and omega-6 oils – the essential fatty acids. ‘Essential’ simply means that the body cannot make this kind of fat itself; you need to eat it as part of your diet, or take it as a supplement.
Polyunsaturated fats are responsible for many different actions in the body. Sufficient levels support cell membranes (which we want to be nicely fluid), hormones, managing inflammation and immunity, mood and memory.
As a rule, omega-6 fats are less beneficial than the omega-3 fats, which are all anti-inflammatory. The ratio between the two is important. This is why prioritising consumption of omega-3s is key, as it’s easier to consume omega-6 fats. Historically, humans ate a good ratio of omega-6 to 3 – ranging between 1:1 and 4:1. Unfortunately, the modern Western diet has changed things for the worse. The ratio is now frequently 20:1 thanks to overconsumption of grains, processed foods, vegetable oils and conventionally raised (rather than grass-fed) meat, all of which contain omega-6 fats.
When the ratio is out of balance it has implications on health conditions such as inflammatory conditions, obesity, heart disease, Type 2 diabetes, high cholesterol and cancer.
For omega 3 fats, concentrate on consuming oily fish twice a week and adding nuts and seeds, especially flax seeds, to your diet.
And fats to avoid:
Trans fats
These are fats that you want to remove from your diet. They are artificial fats that are mostly man-made and can cause cell membranes to become stiff and inflexible. As a result they no longer function correctly. In addition, as they are man-made our bodies do not have the innate information they need to be able to deal with them properly.
Trans fats are harmful to cardiovascular health and have been implicated in Type 2 diabetes, dementia and obesity. Also known as hydrogenated fats, they are mostly found in processed foods such as margarine, biscuits, cakes, crisps and other fried foods. Steer clear!
Why do our bodies need fat?
- It’s a concentrated energy source. Gram for gram, fat is twice as efficient as carbohydrates in energy production.
- Fat can be an energy store. Our bodies store excess fat in the diet for future energy production.
- Subcutaneous fat (the fat that sits just under your skin) helps to maintain normal body temperature and provides some essential padding.
- Fats regulate inflammation, mood and nerve function.
- Every cell membrane in our body is made of fat – the brain is 60% fat.
- Many hormones are made from fat. These are known as steroid hormones and they govern stress, sex, and immune function.
- Fats are actually essential for survival. Experiments on rats in the 1920s showed that when fat was removed from the diet they died.
- Fat is the preferred fuel for muscles and the heart. The brain can also burn fat for fuel.
- Essential fatty acids are required for healthy skin, healthy cell membranes, healthy nerves, healthy joints. They also help with absorption of fat-soluble vitamins A, D, E and K.
So how did fat get such a bad name?
Fat has got a bad reputation. Over the last 70 years low-fat products have been marketed as the saviour of our health. And the message from governments and the media was – and largely still is – that, when eaten, fat gets stored as fat in the body and puts us at greater risk of heart disease.
Part of the problem, of course, is that we use the same word for the fat we don’t want (on the hips, around the middle and so on) and the fat we eat.
The demonisation of fat began when an American scientist called Ancel Keys produced the first ‘evidence’ linking saturated fat to heart disease in 1953. He based his scientific opinion on observational data of heart disease, death rates and fat consumption in six countries (ignoring statistics from a further 16 countries because they contradicted his hypothesis) and assumed a correlation between heart disease and eating fat. As an aside, when another scientist looked at the same research, this time considering all 22 countries’ data, no correlation was found.
Although there might have been correlation between fat and heart disease in the six countries, it was not causal. That is to say that consumption of fat didn’t actually cause heart disease.
A further study on rabbits compounded Ancel Keys’ hypothesis. The rabbits were fed cholesterol (which doesn’t normally form a part of their plant diet) and went on to develop fatty deposits in their arteries. This was hardly surprising when their bodies weren’t designed to eat large amounts of fat.
So what was the alternative?
As a result, governments (and their health care agencies) across the world began advocating a low fat diet. They told us to fill up on bread, rice, cereals and pasta, and opt for low-fat or no-fat alternatives wherever we could.
In response, the food industry jumped on board to create products that better satisfied this new advice. They replaced saturated fats with ‘healthier’ vegetable oils, like margarine and shortening. As we saw above, both of these are trans fats that are now one of the few fats research shows ARE linked to heart disease. Oh, the irony…
The biggest problem food producers found was that when you remove the fat from foods, you need to replace it with something else to make those foods palatable. This replacement became sugar. They couldn’t have opted for anything more detrimental to health. As well as its impact on blood glucose, excess sugar and refined carbohydrates are known to be converted to fat and stored in the body, exactly the (false) claim that was aimed at dietary fat. And so began the obesity crisis we have today.
What are my favourite fats?
You will often hear me talking about ‘healthy fats’. These are the fats that we can include with each and every meal for all the benefits listed above. As part of the balanced plate that I recommend, I advise clients to aim for 1-2 tbsp of these for breakfast, lunch and supper. Adding a little to snacks can also keep them feeling full until the next meal.
Avocados: they go with practically anything and are high in both vitamin E and in healthy monounsaturated fats. I particularly like this recipe for breakfast or lunch.
Coconut oil: apart from helping reduce LDL cholesterol and blood pressure, coconut oil is an anti-fungal (caprylic acid) when used both externally or internally. The ideal replacement for butter in baking and as your oil of choice when frying (though I think it works best taste-wise if you’re cooking something with an Asian influence).
Nuts and seeds: packed with nutrients like magnesium and vitamin E, nuts and seeds bring plenty of essential fats to the table. They make the perfect snack – eat a handful (preferably raw) with a small piece of fruit or spread a little nut butter on an oatcake or apple.
Oily fish: are full of omega 3 fatty acids, which are the building blocks of your sex hormones, so are essential for hormone balance. Remember the SMASH acronym when choosing an oily fish. Opt for salmon, mackerel, anchovies (great stirred into a tomato or bolognese sauce for added depth of flavour), sardines and herring.
Olive oil: use cold pressed organic olive oil (ideally extra virgin) as a dressing on salads, or use in cooking. Previous thinking that olive oil becomes unstable when heated is no longer supported. This makes it a good choice for cooking and roasting.
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