People who took statins to lower their cholesterol levels ate more calories and fat in 2009-10 than did those who took them a decade earlier, raising the question of whether the drug provides a false sense of dietary security.
Researchers who used data from a national health survey found that in 1999-2000, people who took statins ate fewer calories, by an average of 179 a day, and less fat than people who didn't take them. The differences began to shrink, and by 2005-06, the difference was insignificant.
And by 2009-10, statin users had increased their daily calories by 9.6% and their fat intake by 14.4% over the decade. Those not taking statins did not have a significant change, the researchers said. The increase of body mass index -- a measure of obesity calculated by comparing weight and height — also was greater for people who took statins than those who did not.
Diet modifications and medications are used to lower cholesterol levelsas ways to prevent heart disease and other conditions.
"Statins are used by about one-sixth of adults. We may need to re-emphasize the importance of dietary modification for those who are taking these medications, now that obesity and diabetes are important problems in society," Takehiro Sugiyama, who led the research while a visiting scholar at the David Geffen School of Medicine at UCLA, said in a statement.
"Ethical considerations should be included in the discussion. We believe that, when physicians prescribe statins, the goal is to decrease patients' cardiovascular risks that cannot be achieved without medications, not to empower them to put butter on steaks," Sugiyama added,
The study was presented Thursday at the annual meeting of the Society of General Internal Medicine and is being published in the journal JAMA Internal Medicine.
For this study, the researchers used data from nearly 28,000 participants ages 20 and older in the National Health and Nutrition Examination Survey. What they ate was measured with a 24-hour dietary recall, taken by trained interviewers.
The reasons for the changes are not certain, said Dr. Martin Shapiro, one of the authors.
"People are highly variable, and it would inappropriate to make generalizations," he said by phone.
But his own doctor put him on statins and his cholesterol fell dramatically, he said. "Until then I worked relentlessly to limit calories and fat and do all kinds of other good things for my health. To be honest, I was a little less careful" once he saw what medication did.
But Shapiro noted that the study did not track people over the decade, so they are not the same people being weighed and measured each time. In addition, about twice as many people were taking statins in 2009 than in 1999, and it's possible more people who eat more began taking them over the years, he said.
"It's a complicated question, but it seems likely that some people are feeling like they don't have to watch it as closely as they did before," Shapiro said.