You need fat too!

I realize this is something that is hard to swallow, but it's true. You need fat too. Before you blow me off and keep "fat" on your black list read a little further.



You're body is made up of cells. A couple hundred years ago you might have looked at me and just said, "huh?" But thanks to the microscope and some advances in science (as well as public education) I feel pretty confident you can track with me here. Now where were we...ah yes, cells. You're body is made up of cells. Skin cells, stomach cells, hair cells, muscle cells, fat cells and more. Despite the fact that these cells all are part of different organs and systems, they have more in common than you may think. One of the things that all these cells have in common is their outer layer.



Cells have what is called a membrane which is composed of a lipid bilayer. What that basically means is that each cell is encased in a double layer of fat molecules. That's right fat molecules (aka lipids). And an important source for those cell walls is the fat that you eat. The fat you eat and cholesterol that you eat and that your body makes are mostly responsible for making the walls of your cells. The combination of those two components helps to determine how hard or soft those walls are. In the ideal world it would be the perfect combination of not too soft and not too hard, but every person is a little different based on their diet and their genetics.



This is part of the reason that trans fats are such a big deal. Initially when trans fats were invented we thought they were a great cheap solution to always needing plant or animal products, but as we quickly found out it's hard to beat nature at it's own game. By now it is impossible to go into a store without seeing bags of anything and everything labeled "0 Grams of Trans Fat" or "Trans Fat Free." That's because we learned that when trans fat gets included into our cell walls it tends to pack very tightly together. This means rigid cell walls (among other problems). Fats made by people and animals are almost exclusively cis-fats. While trans fats generally make straight linear molecules, cis-fats have some twists and bends in them. They create little extra spaces for molecules to move around and your cell membrane stays "softer" so to speak. Because of all of these problems trans fats are one item I would say are okay to put on the official "bad" list.

Another fat to avoid in excess is saturated fat. Saturated fats have similar properties in your cell to trans fats, but are naturally occuring in animal products and still not as bad as trans fats. This makes intuitive sense because we all are aware that eating a stick of butter or having bacon with every meal (both of which have a large amount of saturated fat) is not a good idea. Saturated fat, though, is not necessarily something to completely eliminate from your diet. For one, it would mean eating almost no animal products which is not a truly healthy or realistic option. In addition, your body can handle saturated fat and deal with it without too much difficulty, but just like any other nutrient if you eat too much of it you will not be happy with the outcome.

Now there are a couple of fats that are good for you. Namely unsaturated fats as well as omega-3 and omega-6 fatty acids. Unsaturated fats are found in nuts, seeds and other plant products and they are generally liquid at room temperature when they are isolated (as compared to saturated fats which are typically solid at room temperature-this is another good indicator of the quality of fat you are eating. Have the solids sparingly and enjoy the liquids). These unsaturated fats are the kinds that will leave your cells' walls soft and happy instead of rigid. Omega-3 and omega-6 fatty acids are important for multiple uses in the body, but they can't be made by humans, so they need to be eaten instead to be included in our bodies.

But now I've been babbling long enough, let's get to the payoff.

If you had to distill all of this information into a quick application it would be this. Don't avoid fat because you think "fat is bad." Fat has twice as many calories/gram as carbohydrate or protein so it's important to eat less of it if you want to avoid packing extra supplies of it on your body. However, it's not necessary to avoid it altogether and isn't good for you to do so either. Try enjoying some almonds instead of potato chips or using olive oil in place of butter. These are good ways to make sure that you get the fat you need without overdosing on the fat you don't need.

I know it's complicated, but you can do it. If you are just tuning in, check out more of this series on the three main nutrients under the Nutrition tags.