Do you really want to get rid of cholesterol? If somebody promised to remove all trace of it from your body, would you agree, thinking that that would eliminate the threat of heart disease? If you say yes, that would be a mistake. Because you would then find it difficult to survive.
What is cholesterol?
It is all over the news, both TV and print, and tons of medical articles are devoted to this rogue. Except that it is not always a rogue.
“Chole” in Greek means bile, while “stereos” means solid. The “ol” signifies that it is an alcohol.
So cholesterol is a sterol, which is a modified steroid.
It is also a lipid molecule, which basically means that it is a type of fat.
Do we need cholesterol?
You better believe it!
Why? Because it is an essential part of the cell membrane of all animal cells. Bacterial and plant cells have cell walls, which are fairly rigid. However, because of the cell membrane, animals, including us, can avoid having a cell wall. Thus animal cells can change shape and move around.
Anything beyond membranes?
Yes!
If you are Mycoplasma, you need cholesterol for growth. But if you are reading this, it is unlikely that you are Mycoplasma.
Assuming that you are a human being, you would need cholesterol for intracellular transport, cell signaling, and nerve conduction.
Vitamins and hormones
Unless you want to pop Vitamin pills and depend on hormone shots, you had better thank God for cholesterol.
The synthesis of Vitamin D and all steroid hormones requires cholesterol. This includes sex hormones and adrenal gland hormones.
So should we eat a lot of cholesterol?
Hold on for a while.
If you are a man weighing 150 pounds (are there any of those around anymore?), your body makes about 1000 mg of cholesterol daily. Yes, makes. Since cholesterol is vital for the structure and functioning of the body, your body does not want to depend on your diet to give it enough of a supply.
Remember, the time of excess is relatively recent. For hundreds of thousands of years, human beings struggled to get enough food to survive and flourish.
So your body makes a lot of cholesterol. As we speak, your body (if you are the above-mentioned hypothetical male) contains 35 g of cholesterol. And most of it is not in the heart or arteries. It is mostly within the cell membranes, performing a vital function.
So how much should we eat?
Good question.
Let us turn to the Dietary Guidelines for Americans (DGA) which has been telling us what to eat and how much since 1980.
In 2010, American men were consuming 350 mg of cholesterol daily, while women limited themselves to 240 mg. The DGA recommended that year that we should keep our intake below 300 mg/day. The rationale, of course, was that if we ate less cholesterol, our blood cholesterol levels would fall, and we would not develop blockages leading to heart attacks.
DGA 2015-2020 advice
The latest DGA report is revolutionary in one regard. It makes no recommendation to limit cholesterol intake.
The report states that “adequate evidence is not available for a quantitative limit for dietary cholesterol specific to the Dietary Guidelines.”
Say what?
Dietary cholesterol does not play a major role in blood cholesterol levels.
Yes, you heard that right.
The amount of cholesterol in your blood stream is not affected significantly by how much cholesterol you eat in your food.
Why?
Most of the cholesterol we eat is in the form of esters, and as such is poorly absorbed.
In addition, if we eat too much cholesterol, and a lot of it is absorbed, the body compensates by making less cholesterol on its own.
There are many factors which have a more pronounced effect on blood cholesterol than dietary intake of cholesterol.
Body weight, age, sex, physical activity, heredity, and consumption of saturated fats and trans-fats, all have significant effects on our blood cholesterol levels.
But what about heart disease?
That, of course, is the million dollar question.
Links between high cholesterol levels and the development of coronary artery disease (blockages in the heart) leading to heart attacks are quite clear.
So what should we do to lower blood cholesterol?
And will that lead to prevention of heart attacks?
And what about the different types of cholesterol?
Conclusions
- Cholesterol is not always bad.
- Without cholesterol, we would not have cell membranes, some vitamins, and important hormones.
- High cholesterol levels are associated with an increased risk of heart disease and heart attacks.
- Cholesterol is of several types.
- The level of cholesterol in your blood is not primarily dependent on how much cholesterol you consume in your diet.
Future direction
- How best can you lower cholesterol?
- Will that affect heart disease?
Stay tuned!
We will address these issues in subsequent posts.