Saturated vs Unsaturated Fat (1)

I am frequently asked, "Dr. Press, I hear so much about saturated and unsaturated fats, and omega-3 this and omega-6 that. What's the deal with this stuff?" Well, it's actually a somewhat complicated question, but the answer is not too hard to understand if we break it down. Since this is a sort-of long topic, I'm going to talk about saturated vs unsaturated in this part, and talk about omega fats in my next blog post.

There are three types of macronutrients, sugars (carbohydrates), oils (fats), and proteins. Recall back to your high school chemistry (yeah, I know you don't want to, but bear with me for a moment :-P ), that atoms can make one, two, or three bonds with each other. Carbon especially likes to do this, and likes to form long chains. So basically, fats are just long chains of carbon atoms, with some oxygen and hydrogen thrown in for good measure.

If you're having trouble visualizing what this looks like, I'll use a metaphor borrowed (really stolen) from Alton Brown's TV show, Good Eats. Imagine a roller coaster, where all the cars represent carbon atoms,

SatFatTrain


and all of the seats are occupied by hydrogen atoms, who represent the people riding the roller coaster.

This is a saturated fat. All of the empty seats have nice, happy people in them.

Saturated fats are solid at room temperature, and melt in response to heat. Examples are coconut oil, ghee, butter, lard, duck fat, and others.

An unsaturated fat then, is one in which there are unoccupied seats on the car.

UnsatFatTrain

Unsaturated fats are liquid at room temperature. Examples include olive oil, sesame oil, fish oil, flax-seed oil, avocado oil, and others. There are two kinds of unsaturated fats, monounsaturated, meaning that there is only one empty seat on the train, and polyunsaturated, meaning that more than one seat on the train is empty.


So, now that you understand the difference between saturated and unsaturated fat, let's talk about why you shouldn't use unsaturated fats for cooking. The more unsaturated the fat is, i.e. the more empty seats, the more vulnerable the fat is to going rancid. When a fat becomes rancid, it means that oxygen jumps into the empty seat on the train. In this metaphor, oxygen represents the annoying, screaming kid that makes a lot of noise, kicks the back of your chair, and generally ruins your ride.

RancidUnsatFatTrain

In the body, rancid fats promote the formation of free-radicals. Free-radicals are chemicals that are super-reactive, and damage cells and DNA. Free-radicals are stopped by antioxidants (and this topic is also quite interesting, but is the subject of another blog post).

Anyway, when you cook with an unsaturated fat, heating it up makes the fat more vulnerable to oxygen getting in, and ruining it. This is why you should never cook with olive oil, or other unsaturated fats. It is much better to use a healthy fat like coconut oil, which has no open seats on the train for oxygen to get in, and doesn't mind being heated up.

If you must cook with an unsaturated fat (and you should avoid doing so if at all possible), only use a monounsaturated fat, rather than a polyunsaturated one. Polyunsaturated fats like soybean, corn and safflower oils must be kept cold, and stored in dark bottles to prevent rancidity. Rancid fats are very bad for your body, and polyunsaturated fats go rancid very easily.


So, breaking it down, cook with healthy saturated fats like coconut oil, only use monounsaturated fats like olive oil for cold, or room temperature applications, and only use them in gentle heating applications if absolutely necessary, and never heat polyunsaturated fats. Store all unsaturated fats in dark bottles, away from light and heat, and keep polyunsaturated fats cold, to prevent them spoiling.

To learn more about nutrition, and healthy eating, call 201-569-144 and make an appointment with Dr. Stephen Press. You will learn how the effects of diet and exercise, as well as vitamins and supplements can all make a huge difference to your health.