Cholesterol is a fatty substance that our bodies use to build and maintain cell membranes and to coat nerve endings. It also forms part of our blood plasma. Cholesterol is needed to metabolise the fat-soluble vitamins (A, D, E, and K). It is cholesterol that is turned into vitamin D when sunlight hits our skin.
Cholesterol is also needed to produce the sex hormones testosterone, estrogen, and progesterone. Without cholesterol, we cannot produce the hormones required to make reproduction possible.
Cholesterol is essential for physical and cognitive function, and every cell in your body needs cholesterol every day.
Given how important cholesterol is to life and reproduction, it should not be surprising to discover that we have our own supply of cholesterol. Our livers produce about a gram of cholesterol every day. However we need about a gram and a half a day, so the rest must come from our diet.
Finally, cholesterol is cholesterol. There’s no such thing as “good” or “bad” cholesterol. There is only one type of cholesterol, and that’s cholesterol. The conventional wisdom would have you believe otherwise, but I’ll explain this distinction in the following posts.