The cholesterol levels of US adults have been dropping since the late 1980s – and not just because of the increased popularity of lipid-lowering drugs,according to a US study.
Researchers from the Centers for Disease Control and Prevention said cholesterol,which is closely tied to heart disease risk,may be looking better because of improvements in diet,including the substitution of vegetable oils for less-healthy trans fats.
They found,in a report published in the Journal of the American Medical Association,that average total cholesterol dropped from 206 milligrams per deciliter in 1988-1994 to 196 in 2007-2010,with a similar decrease in bad LDL cholesterol.
It’s important and significant,the reduction that we see here,but it’s not unbelievable,said Goodarz Danaei,from the Harvard School of Public Health,who was not involved in the study.
Researchers consulted nationally representative health surveys that took blood samples from adults and interviewed them on their medication use. Each survey included between 9,000 and 17,000 people.
Along with a drop in total cholesterol,Margaret Carroll and her colleagues saw average LDL levels decline from 129 to 116 between the survey periods. HDL,or good cholesterol,rose slightly from 50.7 to 52.5,on average.
Guidelines recommend keeping total cholesterol under 200 and LDL below 100,although 100 to 129 is still considered near optimal.
As expected,the use of statins and other cholesterol-lowering medications increased among survey participants,from just over 3 per cent to above 15 per cent during the study period.
However,average cholesterol levels also fell among people who weren’t on the medication,the researchers said. The most recent research suggests about one-quarter of adults age 45 and older in the US are on a statin.
Danaei said the findings support past research also showing average cholesterol is decreasing in the United States,with a corresponding drop in heart disease.
But the question is whether cholesterol levels will continue to fall,giving rising obesity rates.
Carroll told Reuters Health that based on their study,researchers can only speculate about the drop.
One theory is that Americans are eating fewer trans fats as manufacturers cut it out of baked goods,fried food and butter-like spreads.
(The decrease) was probably due to the reductions in smoking (and) the reductions in trans fat in our diet,particularly in processed food,that have occurred over the same time period,said Donna Arnett,president of the American Heart Association,who wasn’t involved in the study.
Carroll said that besides avoiding trans fats and taking any prescribed medications,people can reduce their cholesterol by limiting saturated fat intake,exercising more and losing extra weight.