Fat is probably the most contentious issue in nutrition. Are they as bad for us as we are led to believe? Are they really responsible for the often poor standard of health seen in the majority of the western world? Should we embrace the "low fat lifestyle"? The problem is that there is a huge amount of freely available information around, especially compared to pre-internet times, and much of it is a) out of date, b) incorrect, c) written by people with no formal training or qualifications or d) written using such technical language that for most of us it makes no sense!
In this article, I'd like to shed some light on the seemingly complicated and controversial world of fats so that you can make informed choices about which ones to eat and which ones to avoid.
Fats are classified according to their level of hydrogen content. All this actually means is that fats that said to be saturated are packed to the gunnels with hydrogen molecules and fats that are deemed unsaturated as missing some hydrogen molecules. The amount of hydrogen molecules present in a fat will dictate how a fat looks, tastes and when we eat it. Fat should make up around 20 - 30% of our daily food intake and very low fat diets are actually quite unhealthy as we need a daily dose of fat for our body's to perform at their best. Very low fat diets are strongly linked to skin and hair problems, low birth weight babies, lowered testosterone levels in men, reduced brain function, impaired learning ability, lowered intelligence and eye problems.
Let's take a look at the four main classifications of dietary fats...
1) Saturated fats. As mentioned before, these fats are saturated with hydrogen molecules which make them very solid structures - they are often solid at room temperature e.g. butter and lard. They are chemically inert which means they don't react much when exposed to heat, light, oxygen or chemicals. Saturated fats are found mostly in animal products i.e. beef and dairy (milk, cheese, butter) as well as palm oil and coconut oil and our bodies tend to use saturated fats for energy or energy storage. (Look down at your tummy - THAT'S saturated fat!!!)
Saturated fats are considered as the "bad boys" of the fat family but really this isn't the case. The worst thing we can say about saturated fats is they can make you fat if consumed in excess as they are very calorie dense. Being over fat is associated with a host of negative health concerns but it's not the consumption of saturated fats that is the problem. Being over fat can be caused by over consumption of carbohydrates or even protein. Eating fat can make you fat and being fat can be a health problem but let's not shoot the messenger! Some saturated fat in the diet is not just fine but is actually essential.
The body mostly uses saturated fat for energy and if it doesn't need the energy it will store the fat around your body for later - often in places we'd prefer to be fat free like our stomachs, legs and bums. As mentioned previously, saturated fats are inert so they don't undergo any chemical changes when we eat them. Saturated fats don't clog your arteries, won't cause heart attacks and are actually vital for mineral and vitamin absorption e.g. putting butter on your Sunday roast vegetables means the veggies become even better for you! Saturated fats are ideal for cooking as they don't turn rancid when heated (more on this later) and should make up around 30% of our daily fat consumption.
Speaking of saturated fats, how many of us have been told by "experts" to switch from butter to margarine to improve our health? This is a huge myth that I'd like to lay to rest right now. As we know, butter us made from cows' milk. Very little is added so it's safe to say that butter is a natural food. It consists mostly of saturated fat so is deemed by some as unhealthy but look closer at the alternative - margarine. Prior to the invention of refrigerators margarine didn't exist. It was invented solely because butter doesn't spread when cold. Margarine is a man-made food, more chemical than natural, contains all sorts of additives like E numbers, emulsifiers, acidity regulators, colours, artificial flavours, stabilisers etc. It's basically a chemistry set in a plastic pot. Butter on the other hand has no artificial ingredients, contains vitamins and minerals, is rich in CLA which is an "anti cancer" super-fat and also contains something called Wulzen Factor X which is a substance which prevents calcification of deposits in our arteries! So, in short, butter = good, margarine = bad. Even the so-called wonder-margarines that promise improvements are heart health are no better for you than good old natural butter. Do like your grandparents did and eat butter in moderation - your heart and your taste buds will thank you for it! Incidentally, some cultures revere butter and actually prescribe it as a medicinal health food. It is given to soon-to-be mothers, growing children, the elderly and the sick as a cure all. Food for thought!
Here's a little experiment to try which will hopefully show you that butter is best...buy some margarine and some butter. Leave them both out side by side on your kitchen worktop for a few days. After a while, you'll see the butter discolours very slightly (the outer surface oxidises) but will pretty much stay unchanged. No fungus will grow on it (butter has anti microbial properties which can enhance gut health), it won't go off and, except for maybe a few fly foot prints (!) it will be completely unchanged. The margarine however will most likely have begun to separate, discolour noticeably, have fungus and bacteria growing on it, begin to smell bad and actually go off. Don't eat it! The butter will be quite safe for consumption but the margarine won't do you any good at all.
2) Monounsaturated fats. This type of fat is missing some of its hydrogen molecules and has a single bend in its chemical chain. This means that, unlike saturated fat which is solid, straight and inert, monounsaturated fats are more reactive and liquid at room temperature. The body can use monounsaturated fats for energy but also for important chemical reactions in the body. They are good for our hearts, our hair and skin and our over all health.
This reactivity is good because we can use monounsaturated fats for a host of healthy processes in our bodies but this reactivity also means monounsaturated fats can "go bad" and cause us more harm than good if they are over-heated, exposed to too much light or oxygen or processed too aggressively. For example, the extraction method used when producing olive oil (the most common monounsaturated oil) can greatly affect its healthful properties. Extra virgin cold pressed olive oil is the Rolls Royce of oils. It comes from the first pressing of the olives (hence "extra virgin") with out the application of heat (hence "cold pressed") or solvents. This makes it very healthy. Anything other than extra virgin cold pressed olive oil will have been heated to high temperatures, had solvents used to increase oil yield and come from a second or third pressing of the olives. All these factors mean our once healthy olive oil is now no longer good for us and may, in fact, be very bad for.
To preserve the healthy characteristics of monounsaturated oils (e.g. olive oil) it is important not to over heat them (stir frying is okay, long cooking times/high temperatures however will damage the oil), stick to extra virgin cold pressed oils where possible and make sure oils are stored in an airtight dark glass container away from direct sunlight.
Olive oil is really best kept as a condiment and consumed raw but because it is only mildly reactive, it's okay to cook with it but only for short periods/lower temperatures. Saturated fats are better suited for longer cooking times and higher temperatures as heat doesn't affect them negatively. About 30% of our daily fat intake should be made up from monounsaturated fats.
3) Polyunsaturated fats. This type of oil (e.g. sunflower oil) has lots of missing hydrogen molecules and therefore lots of bends in its chemical chain making it very VERY reactive. These oils are so reactive that when we eat them they are used almost exclusively for reactions in our bodies and very rarely for energy. Polyunsaturated fats are usually described as "Essential Fatty Acids" or EFA for short. They are often sold as supplements and are vital for the health of our hearts, nervous systems, joints and brains - in fat pretty much the entire body will benefit from regular consumption of EFA. The reason polyunsaturated oils are considered so healthy is because of all the fats, they are the most reactive. No sooner have we eaten them they are whizzing around our bodies doing a myriad of useful functions. However, this reactivity is a double edged sword. Polyunsaturated fats are very easily damaged by heat, light and oxygen and should NEVER be heated. Heating polyunsaturated fats creates trans fats which are the true "bad boy" of the fat gang (more about trans fats in a moment). They should be consumed raw, in their cold pressed extra virgin form only and stored in a dark glass airtight bottle. They have a life span of around 4-8 weeks so should not be stored (even correctly) for longer than this to preserve their healthful properties.
As a side note - EFA are excellent anti-inflammatories. They can reduce the pain of some arthritic conditions very effectively. Cod liver oil has long been associated with healthy joints and is a great example of polyunsaturated oils doing an essential job. Around 30 - 40 % of our daily fat intake should be made up of polyunsaturated fats.
4) Trans fats. These nasty little critters are responsible for pretty much everything that saturated fats are wrongly blamed for. From heart disease to clogged arteries to the weak £ and the Cypriot water shortage - it's not saturated fats at fault but trans fats. (Okay - maybe the last two aren't down to trans fats but it would be handy if we could blame them on something!)
Trans fats are "bent" unsaturated fats which have been straightened out artificially which causes great confusion in our body's cells. In chemistry shape matters. Square pegs fit into square holes, round pegs into round holes. Trans fats are treated by the body as one thing when in fact they are something completely different. They end up going places they shouldn't and block the healthy fats from doing their job. It's as though a square peg has been jammed into a round hole and this means other fats consumed a) can't do their healthy job and b) are now surplus to requirements and more likely to be stored around our middles.
Trans fats should be avoided at all costs. They're not hard to dodge if you follow these simple guidelines...
o Don't cook with polyunsaturated fats - use saturated fat or monounsaturated oils instead
o Avoid overheating monounsaturated fats - they do rancid easily
o Cut down on processed and takeaway foods - they often contain "hidden" trans fats
o Switch back to butter from margarine - there are no trans fats in butter!
o Avoid any food which has the word "hydrogenated" or "partially hydrogenated" listed on it's ingredients
o Cut back on shop-bought pies and pastries - home made is best
o Keep your oils in dark glass airtight bottles
o Only buy extra virgin cold pressed oils.
So - to recap...never never NEVER (!!!) cook with polyunsaturated fats! Remember - saturated fats e.g. butter and lard are great for all types of cooking, monounsaturated fats e.g. olive oil are okay for short cooking times/lower temperatures but polyunsaturated fats, whilst healthy if consumed raw, are turned into trans fats at even low temperatures so don't cook with them at all.
I hope from this you can see that not all fats are bad and that some are even very good for us so enjoy your fats (in moderation of course!) and could someone pass me the butter dish please?!
Source: http://EzineArticles.com and https://unsplash.com for the awesome photo :)
Annoying but necessary - I'm not a Healthcare Professional so please check with your Healthcare Professional before changing anything concerning your well being.