Americans’ cholesterol levels dropping, large survey finds
Amid what seems to be a nonstop onslaught of dispiriting information about the health of our nation, here’s one bright spot: Americans’ cholesterol levels have dramatically improved over the last two decades, according to a large epidemiological study published Tuesday in the Journal of the American Medical Assn.
High levels of LDL, or “bad” cholesterol, and total cholesterol and low levels of HDL, or “good,” cholesterol can lead to serious health complications, including a significantly increased risk of heart disease. As this threat has become clear, public health officials have recommended a range of interventions, including the elimination of trans-fatty acids and a reduction in the consumption of unhealthy foods. There’s also the widespread use of cholesterol-lowering statins like Lipitor, which is the bestselling drug in history.
The new study used three large Centers for Disease Control and Prevention surveys called the National Health and Nutrition Examination Surveys-conducted from 1988-94, 1999-2002, and 2007-10 respectively-to determine whether the last two decades have seen a drop in cholesterol. The surveys each included thousands of participants and consisted of questionnaires about health behaviors and medication as well as an actual cholesterol test. That allowed the researchers to be certain that the cholesterol measurements were accurate.
The results are clear: The nation’s cholesterol levels are dropping.
Average levels of age-adjusted total cholesterol dropped from 206 in the first survey to 203 in the second, before dropping further to 196 in the final survey. That value is below the government’s Healthy People 2010 goal for the turn of the 21st century, set at 200. Perhaps more impressively, this goal was met across all age groups, sexes and ethnicities. LDL levels have also dropped over time, from 129 to 116, and HDL levels have risen from 50.7 to 52.3.
Who or what can we thank for these improvements? Though the most obvious answer is the widespread use of statin drugs, the researchers found that they tell only one part of the story: Participants who were not on cholesterol-lowering drugs saw similar changes to their cholesterol as those who took them. In other words, while the drugs almost certainly helped lower the cholesterol of those who took them, other factors seem to be lowering Americans’ cholesterol levels as well.
The authors speculate that the reduction of trans-fatty acid consumption and a decrease in carbohydrate intake may have played large roles, but further data are needed to be sure.
Nonetheless, they are pretty sure what is not causing the improvement: People losing weight, exercising more or eating fewer foods containing fatty acids. The U.S., they point out, has only gotten fatter, and it has made limited headway in increasing physical activity or eliminating the overall consumption of fatty acids.
You can read a summary of the study here.
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