The generic cholesterol-lowering drug simvastatin, previously sold under the brand name Zocor, may diminish the positive effects of exercise in overweight and obese adults, according to a small new study from the University of Missouri. Statins are the most widely prescribed type of drugs in the world and are taken by 56% of people with Type 2 diabetes.
Statin use had been linked with muscle damage and reduced function of mitochondria (the energy centers of cells). Because these medicines are often prescribed along with lifestyle changes, including exercise, researchers sought to determine whether statin use would have any effect on the positive physical changes that typically result from exercise.
The researchers measured cardiorespiratory fitness in 37 obese, sedentary adults with low levels of fitness and at least two risk factors for the metabolic syndrome. The participants were then randomly assigned to 12 weeks of aerobic exercise training or 12 weeks of aerobic exercise training in combination with taking 40 milligrams daily of simvastatin.
At the end of the study period, those on the exercise-only regimen had increased their cardiorespiratory fitness by an average of 10%. In those taking the statin, however, the improvements were blunted, resulting in an increased fitness level of only 1.5%. Additionally, in those on the exercise regimen alone, skeletal muscle mitochondrial content increased by 13%, while in those taking the statin, it decreased by 4.5%.
“Statins have only been used for about 15–20 years, so we don’t know what the long-term effects of statins will be on aerobic fitness and overall health. If the drugs cause complications with improving or maintaining fitness, not everyone should be prescribed statins,” noted researcher John Thyfault, PhD.
Dr. Thyfault suggested that future research investigate whether lower doses of simvastatin or other types of statin drugs similarly affect exercise benefits. Beginning a statin regimen after obtaining a higher fitness level through exercise might reduce the medicine’s effects on fitness, he suggests.
For more information, read the article “Cholesterol-Lowering Drug May Reduce Benefits for Obese Adults” or see the study’s abstract in the Journal of the American College of Cardiology. And to learn more about maintaining healthy cholesterol levels, read the article “Natural Ways to Lower Your Cholesterol.”