Most Americans are now regularly taking prescription drugs, new research has found. Almost 60 percent of adults take some type of medication, and since 2000, the number of adults taking five or more prescription drugs has nearly doubled to 15 percent, raising serious concerns about the potential for adverse interactions. An aging U.S. population, expanded Medicare coverage, and aggressive TV marketing all play a role, but national surveys of nearly 40,000 people suggest the obesity epidemic is the primary culprit fueling this upward trend. Eight of the 10 most commonly prescribed drugs in the United States are used to treat high cholesterol, type 2 diabetes, and other preventable conditions associated with obesity. In fact, the most popular medication in the U.S. is Zocor, which is in a class of cholesterol lowering drugs called statins. Overall use of statins jumped 10 percent over the past decade by 7 percent. “Here in the U.S., we aggressively peddle foods that propagate illness, and drugs to treat the illness that ensues,” Yale University nutritionist David Katz tells HealthDaily.com. “Big Food and Big Pharma are the winners – we and our families, the losers.” Certain medications, however, are bucking the trend. Antibiotic use fell 1.5 percent over the past 10 years, and fewer women are undergoing hormone replacement therapy, which could reflect growing awareness about the risks and side effects associated with overuse of these drugs.