The argument for fat must be made. Despite the past faux pas that “fat makes you fat,” fat is a necessary and nutrient carrying part of eating a balanced and healthy diet. There are a number of reasons for this despite what the manufacturers of “fat free,” products might say.
Fat Soluble Vitamins
I’m sure you’ve heard all the rage lately about vitamin D. And if you haven’t, be expecting an article on this site soon enough. Vitamin D is a fat-soluble vitamin along with A, E, and K. Fat-soluble means that it likes fat so it won’t be able to travel very well in a bloodstream with low lipids. So while we get much of our vitamin D from the sun and not our diet, the fats circulating in our blood can still affect how it gets where it needs to go. The other fat-soluble vitamins are absorbed from our foods however and so eating a bit of oil on your salad (rich in A and K) is actually a great idea.
Cell membrane formation
Your body is constantly making new cells and cells have an outer coating called a membrane. Those membranes are made up of… you guessed it. Fats. Saturated, unsaturated, and unfortunately probably some trans-fats as well for our phospholipid bilayer membranes (did you catch the “lipid,” part?). Without enough fat and the fat soluble vitamins they carry into your system, your body will have a hard time repairing tissues (all of which are made up of cells).
Your brain is made mostly out of fat. In the words of my metabolism professor in college, “You are a fat head and if someone ever calls you that, consider it a compliment.” While it is true that your brain uses glucose (a carbohydrate) for fuel it also needs fat. When I was younger I used to hear that old myth about brain cells. “Once you kill one, it’s gone forever. You don’t get brain cells back,” they would say as they pressed their finger to my forehead. “Oops. That was the last one!” Well that has since been proven to be untrue.
Our brains have stem cells. And if you don’t know what that means then read on. Our brains have blueprints ready and waiting to build more brain cells. Those stem cells can’t lay out the plans without materials, and in the brain a large part of those materials is fat. If you have a child then this is even more important as their brains develop up until about 25 years of age. That means that kids need fat even more than adults! That is, unless you want your kid to be a skinny-head.
We need fats to help our body make hormones. Sex hormones like estrogen and testosterone (which could help with libido and fertility problems) are formed from cholesterol which fat helps us absorb (more on the myths of cholesterol in another article) Eicosanoids are formed as well which are a major part of our immune system. Certain leukotriene based prescription allergy medicines, such as Singulair, are synthetic versions a local hormone formed from an eicosanoid called arachidonic acid. So if you want to look androgynous, have a weakened immune system, or suffer from chronic allergies, then by all means, keep cutting all the fat out of your diet.