Americans' cholesterol levels have significantly improved over the past few decades, because of changes in diet and use of cholesterol-lowering medications. Still, heart disease is the nation's leading killer.
Researchers with health laboratory giant Quest Diagnostics took a closer look at LDL cholesterol, the so-called bad kind. They analyzed a staggering 247 million LDL test results from 105 million adults between 2001 and 2011.
Overall, average LDL levels declined 13 per cent during those years. But the downward trend continued only through 2008 — LDL levels held steady after that, the researchers report Friday in the journal PLoS One.
"It's a red flag that something dramatic happened," said Quest's Dr. Harvey Kaufman, who led the study.
The Great Recession began about the same time, Kaufman said. He wonders if higher unemployment and financial stress affected medication use, diet or other factors to explain the findings.
Not so fast, said Dr. Donna Arnett, president of the American Heart Association. This kind of study isn't representative of the entire population and could merely reflect that healthier people skipped cholesterol tests during tight financial times, cautioned Arnett, of the University of Alabama at Birmingham.
She said more research is needed, noting that government studies haven't yet detected the same trend.