This post is part of a Nourishing Topics series: Truth About Fat. You can read all the posts in this series here.
The word “fat” has such an incredibly negative connotation in today’s modern society. Surely this hasn’t always been the case, has it? When did it change?
Consider for a moment those who live in climates so cold that vegetation cannot grow. Until the modern food industry came along, their only method of survival was to hunt animals. They would eat the entire animal – fat, organs and all – and until modernization, they’ve been mostly free from disease.
What about the French? We don’t have to go back into history – their current diets are laden with fat. Butter, cream, liver, cheese, pâté… all added liberally to their meals. Yet France has an incredibly low rate of heart disease – quoted by Nourishing Traditions as less than half when compared to the United States.
As a country we have been groomed to believe that the fats at the heart of French cuisine are “bad” fats and should be avoided as much as possible. If we’re following this lifestyle and avoiding the fats that have been the foundation of multicultural diets for centuries, then why are we as a society plagued with more disease?
In order to understand the answer, we need to understand the basics.
What is fat?
Just like carbohydrates, proteins, vitamins, minerals and water – fat is a nutrient. Wikipedia defines nutrient as “a chemical that an organism needs to live and grow, or a substance used in an organism’s metabolism which must be taken in from its environment.”
In the human body, fat is used as energy and as a means to absorb vitamins that cannot be absorbed by any other means (vitamins A, D, E and K). Ever pour oil into a pot of water? Oil and water don’t mix. Because of its chemical make-up, one simply cannot dissolve into the other.
Our bodies require a variety of nutrients, some of which are water-soluble and some that are fat-soluble. The fat-soluble nutrients do not mix with water (like in the jar). The only way our bodies can absorb and use fat-soluble nutrients is by consuming something they do mix with – fat.
The mere fact that we can stand upright and rigid without our organs succumbing to gravity and falling to our feet is because of fat. We are born with fat for one purpose and as we grow, our body creates fat for a multitude of purposes. Those reasons include supporting our organs and protecting the body.
Our bodies purposely create and store fat as a source of energy. Humans were engineered to be able to thrive when feasting and survive during famine. When no other food source was available, we survived famine using the fat reserves our bodies had created.
Here’s a fun fact to put it into perspective: one pound of fat provides about 3600 calories. If no other physical activity was required of me, one pound could fuel me for nearly three days!
Fat is more to our bodies than just energy though. It’s also the catalyst for many of body’s natural processes, including growth, immunity and reproduction. There only two ways our bodies can get this vital nutrient: make it, or eat it. This is a food blog, and we will talk about food, but we first need to talk a little bit about the science behind the food. 🙂
Main Types of Fat
All fats can be narrowed down to two main types: saturated or unsaturated. Unsaturated fats can be further classified as either monounsaturated or polyunsaturated. If my stories and mental picture descriptions haven’t given it away, I’m a visual learner. Here’s a chart that help explains it:
The chart may look simple now, but we’ll fill it up in no time. 😉
Saturated fats have their name because of their molecular structure. Here’s what a saturated fat molecule looks like:
Notice how all the carbon atoms (C) are filled, or “saturated” with hydrogen atoms (H). The fact that every carbon atom is saturated is a good thing. It makes this type of fat structurally strong, less likely to break and there’s no room for roaming free radicals.
Free-radicals are extremely reactive single atoms or clusters that attack healthy cells. They seek molecules with a weakness so they can latch on and do their damage. When they find their prey, they can trigger mutations in tissue, blood vessels and the skin.
Again, the are no weak points in saturated fat where free-radicals can attack. This is a good thing. Thanks to their solid stature, saturated fats are excellent for cooking, especially at high temperatures.
Here’s the molecular structure for monounsaturated fats:
See that red #1? That’s where the molecule is exposed. There’s only one opportunity for free-radicals to attack this type of fat, hence the prefix “mono.” These type of fats are usually strong, but not as strong as saturated fats. When not used correctly, monounsaturated fats can become oxidized or rancid and become even more susceptible to attack by free-radicals. This means extra care should be taken when using monounsaturated fats in our food and especially while cooking.
Here’s the last molecule for the day, the polyunsaturated fat:
Notice how it’s similar to monounsaturated fats with the unprotected carbon atoms. The big difference though is that polyunsaturated fats have two or more exposed areas. This is not a good thing. These two (or more) areas allow these fats to go rancid very easily and because of this, polyunsaturated fats should not be used in cooking, especially during any process that uses heat.
The Type of Fat Matters
It would be easy to say that we should only eat “this” type of fat and completely avoid “that” type of fat, but the reality is that all fats are some sort of combination of saturated, monounsaturated and polyunsaturated. However, the more a fat falls towards the saturated end of the scale, the stable the fat is, the less likely the fat can harbor damaging free-radicals… and I think we can all agree that avoiding cell mutations in our bodies is a good thing. 😉