Can you recall the day the butter disappeared, eggs were banned and avocados were only found in "What fruit is that?" book? It happened in the early 1980's in our house. As fast as they disappeared, margarine boldly marched in and "Skinny Milk" made front row in the fridge. Chips were no longer cooked in tallow because canola oil was the new answer to frying. This saw the transition from REAL or natural fats and oils to manufactured and processed sources of fats and oils.
What is the difference between fats and oils?
Fats = solid at room temperature. Oils = liquid at room temperature.
Why were our good fats taken away?
As early as the 1950's a theory called the lipid hypothesis emerged. The concept of the theory is that dietary saturated fat and cholesterol clog arteries and cause heart disease and vessel disease. The theory gained support over the following decades. Studies performed by Ancel Keys were supportive of this theory however the methodology of the study is highly questionable and remains the centre of great criticism and controversy today. On the basis of this questionable research, dietary advice emerged stating that reducing saturated fat in the diet will reduce cardiovascular disease. Exit butter, coconut oil, bacon, eggs and full fat dairy. Enter margarine, vegetable oils and low-fat dairy.
Earlier in 2014 however, a meta-analysis found no evidence to clearly support the cardiovascular guidelines that "encourage high consumption of polyunsaturated fatty acids and low consumption of total saturated fats". (Chowdhury et al, Annals of Internal Medicine, 2014, 160(6);398-406). This information has led to the re-stocking of many fridges and pantries with long lost fats such as butter and tallow and avocado is back on the spelling list in schools.
Why do we need to eat fats and oils?
1) Fats are our building blocks. Our cell membranes contain fats and they are used for function, strength and integrity. The brain in particular is fat dense with 60% of the brain is composed of fat.
2) Fats provide energy.
3) Essential fatty acids are the omega 3 and omega 6 fats and they cannot be made in the body. They must be supplied by food. They play an important role in inflammation, growth, reproduction, wound healing, production and signalling important hormones (example insulin, oestrogen) among many other things.
4) Fats support nerve functioning. Myelin is a fatty substance which wraps around nerve cells so they can transport electrical signals.
5) Fat is the transporter of vitamins. There are four fat-soluble vitamins our body requires which are often found in foods containing fats and in the body they are transported to where they are needed by fat. These vitamins are A, D, E and K.
6) Fats are important in bone health. Fat (especially saturated fat) is important in calcium absorption.
Fats and oils to stay away from
I mentioned earlier that our REAL fats and oils were replaced by manufactured, processed oils. Did you know that the canola seed was only developed in a laboratory in Canada in 1974? Canola actually stands for Canada - Oil. It is a modification of the rapeseed plant. The guy who developed it Dr Baldur Steffanson went on later to work for the company who later became MONSANTO to develop Round-Up resistant canola plant. This"food" that has only been in our diet for 40 years and has been introduced without any human toxicity testing. You need to be mindful that it is often the ingredient on the packet used when "vegetable oil" is listed.
Other fats and oils to avoid include soybean, grapeseed, safflower, sunflower, cottonseed and margarine.
These have only been in our human diet for the last 100 years. If you look on almost any packet you will see vegetable oil as a listed ingredient. It is a cheap substitute for natural oils and fats.
Besides the manufacture process of these oils, there is another very important reason why they should be minimised as much as possible. Earlier I mentioned the two essential fatty acids - omega 3 and omega 6. These oils are high in omega 6 fatty acids. What this means is that they are PRO-inflammatory. If you could imagine taking a wire brush to your skin and repeatedly rubbing it, it would cause it to flare up, possibly bleed and be painful. If you imagine inside your body, by having too much of this oil, it can initiate inflammation inside vessels and organs. Over time this can lead to almost any disease in our modern spectrum of illness and not just in us but in our children (if you think about the fact that all our babies cells are built out of fats and oils that we consume). We consume up to 30 times today the amount of omega 6 fatty acids compared to 100 years ago. This rate has risen exponentially since the introduction of vegetable oils.
Which oils to use?
Real fats and oils! If it comes from a plant or an animal (which has been grass fed not grain fed - grain feeding = omega 6 whereas grass feeding = omega 3) with minimal processing, then it is a natural source of vitamins and nutrients.
For cooking at high temperature - coconut oil, tallow, butter - more stable at higher heat.
For no/low/moderate heat olive oil. For dips, salads you can use olive oil, flaxseed oil, macadamia oil.
Other sources of essential fatty acids are oily fish, sea plants, flaxseeds, walnuts, grass fed meats and some vegetables (brussel sprouts and cauliflower in particular).
A note on eggs: poor eggs have been given a bad reputation as a food to avoid because they contain cholesterol. Eggs actually raise HDL levels in the blood (which are the "good" cholesterol) and change the particle size of LDL ("bad" cholesterol) from small harmful particles which are harmful to larger denser particles which are not harmful. Eggs have been shown in a meta-analysis to "not be associated with a risk of coronary heart disease or stroke". (Rong et al, BMJ, 2013; 346:e8539)
When to eat fats and how much?
Eating good fats is important. A particularly important time to ensure good fat intake is during periods of stress where extra hormones (cortisol) are required and the fats are important in their production.
One of the best kept secrets about fats is that by eating fats with every meal, you are less likely to be hungry soon after eating as you are when you eat a carbohydrate based meal. Think about how you feel after eating a breakfast of eggs and bacon or salmon and some veggies compared to a bowl of cereal. If you have a salad at lunch, make sure you drizzle some oil on it for that same reason. It is really important to include a small amount of fat with every meal; and you may also find that snacking becomes less frequent and time between meals stretches!
There is however a disclaimer to this...........
Yes there are many benefits from switching to eating fats and oils from real food sources however eating fats in conjunction with refined carbohydrates and sugar is still essentially eating our standard Australian diet. It will remain highly inflammatory (refined grains and sugar are highly inflammatory) and will be a source of extra energy.