Fats are good for you, in fact fats are essential to our well-being. That is not the impression we would get from the media although explanation of the concept of good and bad fats is becoming clearer.
Fat is only a problem if it exceeds more than 15 to 20 per cent of our diet. Having said that, it is important that the fat that we eat is ‘good’ fat, containing the sort that we can utilize, and has associated with it the vitamins known as the fat-soluble vitamins that cannot be found in water-based foods.
Firstly let us understand the different terms that we so frequently read about.
Essential fatty acids – are those that humans cannot synthesize and must therefore be obtained through the diet. Fats are made up of fatty acids, which are principally carbon, hydrogen and oxygen molecules joined together in a variety of combinations.
Triglycerides – are three fatty acids joined together, which vary in their length and car-bomhydrogen ratio. Dietary fat is mostly composed of triglycerides. These are found in both animals and vegetables.
Phospholipids and glycolipids – these are triglycerides that contain phosphorus and other molecules. These are important constituents of biological membranes, blood plasma and most cell walls. Nervous tissue is made up of a type of phospholipid known as sphingomyelins and it cannot function without them.
Cholesterol and its derivatives – cholesterol is in fact a steroid. Are we not generally led to believe that steroids are bad? Absolutely so if they are artificially manufactured , but in fact life depends upon them. Cholesterol is the starting point for hormones of the adrenal glands and sex glands, vitamin D and the bile acids, all of which are essential to life. Cholesterol is discussed elsewhere .
Vitamins A, D, E and K- are all fat-related vitamins that do not dissolve in water and can only be found in fats.
Saturated and unsaturated fats – if a fatty acid chain has all of the carbon atoms linked together with a single electromagnetic link, it is said to be saturated. If the chain is joined by more than one bond, it is unsaturated. The fewer the links, the harder it is to break down the chains, making saturated fats more difficult to utilize as energy and increasing the tendency for the body to store these poorly utilizable fats. The more saturated the fat, the easier it binds together and a simple way to understand whether a compound is heavily saturated or not is by its solidity at room temperature. Beef, pork or lamb fat is hard, butter less so and olive oil is a fluid. There are more saturated fats in animal proteins than in vegetables.
It is important to remember that many fats are necessary and good for us, particularly those known as the omega 3 and omega 6 oils found in fish oils, eicosapentaenoic acid and linseed. Getting the gist? Saturated fats are ‘bad’, unsaturated fats are not.
If a fatty acid chain has many bonds it is said to be polyunsaturated and having more bonds is weaker as a chain and thus more readily broken down. As a general rule, these are therefore healthier and are recognised by remaining a liquid at room temperature, as mentioned above. Polyunsaturated fats also have the additional benefit of being cholesterol-free and although this is not necessarily a good thing , as a general rule low-cholesterol foods are liable to do us less harm.
Hydrogenated fats – unfortunately there is another twist in the tale and this is the term hydrogenated fats. A hydrogenated fat is one that has had additional hydrogen ions added to it, usually by being exposed to heat and altering its natural structure. An otherwise ‘good for you’ polyunsaturated fat may become harmful by being heated. Much to our misfortune, the food processing industry takes healthy polyunsaturated vegetable oils and processes them in such a way that they are exposed to high temperatures, oxygen and light and sell them to us proclaiming great health benefits.
Trans-fatty acids. Lastly, we are hearing about products that are free of trans-fatty acids. These are altered forms of the EFAs, altered by the heat and oxygen exposure of processing. Trans-fatty acids cannot be used by the body and actively interfere with the biochemistry of one of the body’s protective compounds, known as prostaglandin E,.
So where are we? We should not eat animal fats, including butter, because of its saturated status and cholesterol, but we cannot eat the vegetable oils that are provided to us because the processing of these otherwise healthy polyunsaturated oils is generally hydrogenated. Unfortunately, these are the facts.
We need to reduce the amount of fat in our diet to an absolute minimum until the ‘powers that be’ can produce an easily available non-treated polyunsaturated fat. At the moment these are called ‘cold-pressed’ and are available in health-food stores and some supermarkets.
If polyunsaturated, cold-pressed, non-hydro-genated and low or no trans-fatty acid fats and oils are not available , you may choose to give up. Do not do this. Persevere. The ‘good stuff’ is available and at the end of the day if you have small amounts even of the most refined and dangerous compounds your healthy body will deal with it efficiently and extract the necessary EFAs and vitamins. Purified supplements can be used on a daily basis and eating the occasional oily fish will provide the necessary requirements. Remember that the body must have fats to survive, and bad is better than none!
Recently there has been research into production of a fat that carries the taste and flavour associated with the food group but does not have the capability of being stored in fat stores. The food industry is looking forward to the fortune that such a food product may confer since it would allow everyone to enjoy their cream teas and fried foods without worrying about weight.
Be very wary. There have been no long-term studies and we have little idea of how the body will react to this extremely artificial substance. Like genetically engineered food , this is a compound that should be avoided for at least the next 20 years. Then, if no adverse affects have been reported, we may be able to use it. Be very sceptical about ‘scientific studies’ because those that show negative aspects are not likely to be published. Millions of dollars have gone into the production and assessment of this food and the food industry is not going to give up their profits easily.
The body has developed an enzyme and biochemical system over millions of years of evolution. We are the most complex of organisms and, some would say, the most successful on the planet. We did this because we learned and developed abilities over a long period of time, allowing us to deal with most things that nature threw at us. Now our bodies are compromised by an array of unnatural chemicals that are changing at an alarming rate. Our evolutionary capabilities to deal with these compounds cannot keep up and in an attempt to defend ourselves we are storing these additives, preservatives, insecticides, pesticides, household chemicals and airborne pollutants, which are known, in many cases, to alter our genetic material and trigger diseases as serious as cancer. Wherever possible, just do not eat them.