The Importance of Cholesterol

Cholesterol certainly seems to have gotten a bad rap these days, with the dominant message out there being to get your blood cholesterol levels as low as possible.

But did you know that the adult liver produces about 1,000 mg of cholesterol a day? Obviously something we are producing that much of has some very important functions!

Cholesterol is necessary for life:

• Cholesterol makes up 30% of the membranes of every cell in your body. It is important for transferring things in and out of your cells: nutrients in and waste products out.

• It is the raw material for building our steroid hormones. Steroid hormones are estrogen, progesterone, testosterone, and cortisol, an important stress hormone. It is also the starting molecule for vitamin D synthesis.

• It makes myelin, the insulator of your nerve cells. Myelin acts like the plastic outer coating on the electric wiring in your home.

• Your brain contains 20% of all the body’s cholesterol: a higher percentage than any other part of body! It is protective in the central nervous system. There is an interesting article in Scientific American, April 2019 called “This Is You Brain on Cholesterol” which argues that high cholesterol may be beneficial in later life, for good brain health and mental function.

 The good, the bad and the ugly:

Lipoproteins are carrier proteins, made in the liver to carry fats like cholesterol around in your bloodstream, which is water based. This is a clever work-around, because we know that fats and water don’t mix! To get cholesterol to our cells, the body makes little fatty bubbles to transport it through the blood.   

LDL (low density lipoprotein) takes the cholesterol out from the liver to the rest of your body to:

• Build new cell membranes 

• Make sex hormones and make other steroid hormones

• Make “insulation” for neurons, including in our brain 

  And it also plays a part in many other metabolic processes

High LDL is considered a risk factor for heart disease, even though every cell in your body needs it! This is another case where neither excess nor deficiency is optimal.

HDL cholesterol, the “good” cholesterol, removes cholesterol from the arteries and carries it back to the liver for disposal. Higher levels of HDL cholesterol seem to reduce heart disease risk. You may genetically be blessed with high HDL, but you can increase it through regular exercise, healthy fat consumption (fish, nuts and olive oil), weight optimization and avoiding smoking.

Lipoprotein A is a genetically determined inherited form of LDL that significantly increases the risk of cardiovascular disease, heart attack and stroke. It contributes to plaque formation in the arteries and blood clots, and affects roughly one in five people. Lipoprotein a is not part of routine lipid panels, but adults should consider getting tested once in their lifetime. Because this is a genetic factor, and very difficult to change, other heart healthy habits, like diet, exercise, stress relief, blood pressure and diabetes management, become even more important to reduce overall risk.

In the era of statins, there is a big push to get cholesterol as low as possible. But lowering it to protect the heart may accidentally have adverse effects on other systems. This whole issue is  controversial, and information is changing all the time. The well-known functional neurologist Dr David Perlmutter, who is concerned about the use of statins to push cholesterol lower and lower, has  often said, “We will have a whole generation of old folks with good circulation but reduced brain function”!

As science continues to learn more (and change its mind), we can say it is time to banish the egg myth. It was long thought that eggs contain cholesterol, therefore must increase blood levels of cholesterol and cause problems. But egg yolk is also a good source of choline, which is a good nutrient for dealing with cholesterol metabolism. Egg has protein, cholesterol and the choline to help process it: It’s a package deal: nature can be wise!!