LDL and HDL: Neither good nor bad; just doing their jobs

I’ve just finished watching a French-made, feature-length documentary called, in English, “Cholesterol Capers: The Damaging Lunacy of theDiet-Heart Hypothesis.”   (It has English sub-titles, in case you’re wondering.)  It’s mostly about debunking the notion that saturated fat and cholesterol cause heart disease.

Anyhow, I liked the way one of the French scientists discussed HDL and LDL—the supposed “good” and “bad” cholesterol, respectively. In the first place, HDL and LDL are not types of cholesterol, which, by the way, is a sort of alcohol. They are lipoproteins: packages that carry fats, cholesterol, and proteins to and from the liver to various organs. The term density refers to the proportion of protein in the packages. The less protein, the more fats and cholesterol (low density lipoprotein or LDL); the more protein, the less fats and cholesterol (high density lipoprotein or HDL). The scientist in the film described the lipoproteins as “little submarines”. 

The liver produces both LDL and HDL. LDL is the little submarine containing cholesterol, fats and protein that carries its cargo to the organs (cells) that need it. Sometimes a cell will have too much cholesterol. To handle this problem, the little HDL submarine shows up and picks up the unwanted cholesterol as well any other excessive materials and takes it to the liver. This is why LDL (the cholesterol delivery submarine) is considered “bad” and the HDL (the cholesterol collection submarine) is considered “good.”

But, as the scientist says in the film, “To show how this story of good and bad cholesterol is absurd,” picture the liver a hospital and an organ as the scene of an accident. The ambulance going to the accident would be considered bad, while the ambulance going to the hospital would be considered good. Both, of course, are necessary. What's more, new research has shown that people over 60 with the highest levels of LDL lived the longest.

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