Tiki looks at fatsFatty facts : monounsaturates explained

You've probably seen adverts for 'low-fat' foods, or products 'high in polyunsaturates'. Fats are an important part of your food, but there are different sorts. Some are good, some bad and a couple vital. Here's a simple breakdown of the three basic types. All fats - also called 'lipids'- are made of tiny chains of carbon atoms, like a sort of backbone. These carbon atoms attach to each other to make the chain, but they also have side links to atoms of hydrogen. It's the length of the chains and the way in which the carbon atoms link to each other which makes different sorts of fats. Each type of fat is made up of three fatty acid chains connected to a type of alcohol called glycerol. If you think that's complicated, just try pronouncing the scientific name given to fats: triacylglycerols (or triglycerols for short).

Fat name Where you find it What it's made of Is it 'good'?
monounsaturated fats (MUFA) some vegetable oils, particularly olive and canola; some fish a chain of carbon atoms which has space for one more hydrogen atom (double bond) yes
polyunsaturated fats (PUFA) most margarines a chain of carbon atoms which has space for several more hydrogen atoms (several double bonds) some are. Two, made up of what are called Essential Fatty Acids (EFAs*), are vital for humans. You only need tiny amounts though
saturated fats meat and dairy products like butter, cheese and full-fat milk a chain of carbon atoms which has no more space for any hydrogen atoms, so it is said to be 'saturated' with hydrogen. 'Hydrogenated' fats like you find in margarines started life as unsaturated vegetable fats (usually oils) but have, in processing, had most or all of its double bonds broken by adding more hydrogen atoms. Why? To make a fat which you can spread on your bread. no

* In case you really want to know, the two EFAs are called alpha-linolenic and linoleic acid. Other important fatty acids have even longer names: arachidonic, docosahexaenoic and other horrors! Humans need these but they can make them in their own bodies from the two EFAs. The best EFA sources are vegetable and fish oils.