food and nutrition


Question: What is the difference between trans fats and unsaturated fats in idiot-proof language? I understand that trans fats are a form of unsaturated fats but a bad one? Leading to heart disease? While most unsaturated fats are good for the hearth (see fat fish eaters etc.)?

Answer: Fats are part of a larger group of macromolecules (macromolecule: made up of lots of smaller subunits called monomers) called lipids. Have you ever heard of the term lipid bilayer? That's what your cell's membranes are made out of. Your cell's membranes have to be very fluid in order to function. This is a problem, because the fats have very long chains of carbons on them that tend to stick to one another (something called van-der-waals forces). What your body does to increase fluidity of its membranes is include non-saturated fats. The good fats are called "cis" unsaturated fats. What this means, is that the carbons don't go in a straight line. Halfway down the carbon chain, it changes direction and pokes out to the side. This causes the fatty acids to not pack together so tightly. cis fats are common in nature, especially in fats derived from plant products. Trans-fats, on the other hand, are NOT found in nature. They are created by something called "partial hydrogenation" which is typically done to make something melt at a higher temperature. Margarine, for instance, is a plant derived alternative to butter. If they had taken the plant fat straight from the plant and tried to make a stick out of it, it would melt far too quickly because the fats don't stick to each other well enough. So, they partially hydrogenate it to give it a higher melting point. Your body has no natural mechanism to break down trans fats. We have enzymes capable of breaking down saturated fats, and cis unsaturated fats, but since trans fats didn't exist long ago, we haven't evolved a way to get rid of them. Trans fats don't look like cis fats, in that they don't increase the fluidity of the membrane of your cells. In fact, they act just like saturated fats and make your cells function less efficiently.

Related News and Products