You’ve heard a million times that there is “good” cholesterol (HDL) and “bad” cholesterol (LDL). Recently I got my cholesterol measured. My LDL was 151 mg/dl. The test results were written on a form that said your LDL should be “Below 100 mg/dl. Below 70 mg/dl if High Risk.” The person who handed the results to me said, “These are not the best results . . . ”
How concerned should I be? A 2005 study in the Journal of the American Geriatric Society surveyed several thousand “elderly people [who] were recruited from a general Italian population, and mortality was monitored from 1983 to 1995.” The emphasis of the study was on whether LDL was good or bad.
People with more LDL lived longer. You read that correctly. For women, mortality was lowest at the highest level of LDL. For men, mortality was higher at the highest level of LDL (60 deaths/1000 patient years) than at the next highest (50), but still lower than at the lowest level of HDL (90). Going from the lowest to the highest levels of LDL is associated with a one-third decrease in mortality, in other words.
What should I make of my 151 mg/dl? To convert to the units of the paper (mmol/L), I needed to divide by 39. 151/39 = 3.9. Looking at the graph relating mortality to LDL, an LDL concentration of 3.9 mmol/L is where the mortality vs LDL function reaches a minimum — the lowest mortality. According to this study, my LDL is optimal.
Thanks to Joel Kauffman.