Let's chew the fat
Most of us have had it drummed into us that fat is bad and we should only be eating food low in fat to prevent heart disease, obesity, diabetes and a host of other preventative diseases. However, does the evidence reflect the guidelines we have grown up on? To look at this properly, we need to go back in time and look at the story of saturated fat.
The thinking that saturated fat is bad for you originated from one man in the US – Ancel Keys. He had a hypothesis that high cholesterol caused heart disease, and that because fat (especially saturated fat) increases cholesterol, it must be the driver of heart disease. I will write much more about that story in another blog, but suffice it to say that he got a large amount of Cardiologists and Government agencies on board by publishing studies from 6 countries (and later a 7tth), showing a strong association between fat intake and heart disease.
However, there are 2 major flaws with this:
Association does not mean causation – we now know that cholesterol does not cause heart disease per se, and that cholesterol is raised if you are chronically stressed or have systemic inflammation – both more direct contributors to heart disease.
Most importantly, his research was fraudulent! He actually studied 22 countries, but because the data did not fit his theories, he cherry-picked the 6 countries whose data best fit his theory. This is the complete opposite of good science.
There are also a lot of flaws with subsequent studies that came out to show a link between saturated fat and heart disease, such as researcher bias, publication bias, poor study design, the possible inclusion of harmful trans fats under the saturated fat umbrella, and a poor understanding of the metabolic drivers of heart disease.
Now that we have a better understanding of the metabolic drivers behind heart disease, and having completed some better designed studies, lots of researchers are now saying that the current government guidelines on fat intake do not reflect the evidence. We now understand much better that total cholesterol does not cause heart disease and even LDL is not a good measure; and that HDL is even more protective than we once thought.
What is emerging are the dangers of oxidised LDL, small dense LDL particles, high triglycerides as well as low HDL and other factors like inflammation, high blood pressure, central obesity and diabetes. These are all independent risk factors, and when you get combinations of them it points towards metabolic dysregulation at a cellular level.
From a cholesterol perspective, what we now know is you should strive to have as high a level of HDL as possible and minimise your oxidised LDL and small, dense LDL – big fluffy LDL are not pathogenic and shouldn’t be of any concern. You should also keep your triglycerides and blood sugar under control.
Your diet has a big impact on all of these, so let’s discuss the interactions between fat, carbohydrate and these risk factors.
The Fat Story
When we’re talking about fats, we know that monosaturated fats are actually very good for heart and brain health. Recommended examples are extra virgin olive oil, avocado, avocado oil, any nut oils (except peanut) and unsalted, raw nuts.
Saturated (SFA) fats have been unfairly demonised. As I mentioned above, they increase your level of protective HDL and encourage big, fluffy LDL and do not induce damaging, small sense LDL . So, a moderate amount of saturated fats is perfectively fine. Don’t worry about the fat in dairy either – eat a moderate amount of full fat dairy, eat fat on meat (as long as it’s grass fed) and coconut. Avoid processed fats, trans fats and vegetables oils – stick to stuff low on the human interference factor and you’ll be ok.
With this in mind, here is a list of great cooking fats, which we cook with regularly in our family. If you’re going to fry foods, especially at high temperatures, you should be using saturated fats, as they don’t become oxidised. So this list is good, not just because they’re safe to cook with, but also because they taste so good!
Extra Virgin Olive Oil (EVOO)
This should be your go to fat for sautéing and medium temperature cooking. Whilst normal olive oil has a smoke point of 140 degrees, extra virgin is 210 degrees – and it also maintains most of it’s polyphenol content after frying, so is the healthiest fat to use. As well as this, when you sautee vegetables in EVOO, there is a chemical reaction that creates a class of fatty acids known as nitric fats, which are protective for your heart and brain. Make sure it is cold-pressed, as heat-pressed oils can already be oxidised. But be aware some of the polyphenols will deteriorate at temperatures of around 150-160 degrees celsius, so for higher temperatures, you should use saturated fats.
Ghee is clarified butter, and it’s popular in Indian cooking. Because the milk solids have been removed, it’s very low in lactose and is almost entirely fat – mostly saturated. Use ghee to brown meat, top a few teaspoons on a roast and add to roast pumpkin or sweet potato. A tablespoon of ghee contains 8g SFA, 3.7g MFA fat and 0.5g PUFA.
Along with ghee, coconut oil is one of the best fats to cook with because it’s almost entirely saturated. In fact, coconut oil is more than 90% saturated fat. While this makes it the devil according to the government guidelines, this is not the case. Coconut oil has some unique properties. It is a special type of saturated fat called medium chain triglyceride (MCT). Unlike other fats, MCTs do not require bile acids for digestion. This means they are easily absorbed in the upper part of the small intestine. Coconut oil is also rich in lauric acid, a fatty acid found in breast milk that is anti-fungal, anti-bacterial and anti-viral. We are known to eat it my the spoonful! Mix it with almond or macadamia nut butter for some added goodness. Coconut oil has 4g of SFA, 0.3g of MFA
Lard is very popular in cooking and baking because it has little flavour. It’s an incredibly versatile fat and can be used to brown meat and roast vegetables. Unlike olive oil, vegetables roasted in lard do not get soggy or greasy, but stay crisp with a wonderful flavour. A tablespoon of lard has about 6g MFA, 5g SFA and 1.6g PUFA.
Potatoes roasted or fried in duck fat…. divine! Before rancid, industrial oils appeared, the French cooked their fries in duck fat!. Roast your veggies or home made chips in duck fat and you’ll discover why the French love it so much. A tablespoon of duck fat has 6 g MFA, 4 g LCSFA and 1.6 g PUFA.
Good quality, grass fed butter has an amazing taste and despite it being demonised, it’s very good for you. It is full is vitamin A, E and K2 (the latter involved in calcium metabolism). It is a great fat to put on fish, low heat scramble eggs in or slow cooked stews. Butter has a lower smoke point than the other fats, which makes it less suitable for high temperature cooking and it burns easily. A tablespoon of butter contains 7.2g of SFA, 2.9g of MFA and 0.4g of PUFA.
A Word on Commercial Vegetable Oils
In our house we avoid these like the plague as they are high in Omega 6 fats. Whilst some Omega 6 fats are necessary for good health, at higher amounts they start to trigger dangerous inflammation at a cellular level. We get sufficient Omega 6 fats from eating vegetables, but using vegetable oil for cooking is, in my opinion, one of the worst health recommendations we have made. Commercial food processing destroys a significant amount of essential fatty acids, and polyunsaturated oils (Omega 3 and 6) are unstable and very quickly become rancid. Oxidized fatty acids are dangerous to our health, and unless you buy cold-pressed oils, the actual process of expelling the oils using heat (to get it out of the plant in the first place) will cause oxidisation.
The bottom line is to eat food that is real and cut right down on processed foods. This includes your fats. The best thing you can do today is throw away your margarine and your vegetable oils and replace with the fats listed above. You are doing this for your health and your tastebuds!