For the first time in nearly 50 years, the average cholesterol level for U.S. adults is in the ideal range, according to Associated Press reports.

Results from a recent national survey conducted by the Centers for Disease Control and Prevention that included blood tests found the total average cholesterol level dropped to 199 last year. Experts consider 200 and lower to be ideal, the survey said.

Experts say the growing use of cholesterol-lowering pills in middle-aged and older people is believed to be a key reason for the improvement. When the survey began in 1960, the average cholesterol was at 222, AP said.

While Americans have gotten much heavier since then, they’ve been able to lower their cholesterol with powerful drugs that carry few if any side effects, according to AP.

Doctors’ groups have increasingly recommended more aggressive use of these drugs in patients seen to be at risk from heart disease. Cholesterol screenings have also helped. According to the CDC report, two-thirds of men and three-fourths of women had been screened for high cholesterol in the previous five years, AP said.

This has led to cholesterol medications becoming the top-selling class of U.S. drugs, and sales have grown steadily from about $13 billion in 2002 to nearly $22 billion in 2006, according to IMS Health, a consulting company that monitors pharmaceutical sales.

The CDC collects data in two-year intervals, AP said. The new results are based on a national sample of about 4,500 people age 20 and older from 2005-06. The new level of 199 compares with 204 in 1999-2000.  Researchers also found that the percentage of adults with high cholesterol, 240 or higher, dropped to 16 percent, down from 20 percent in the early 1990s, and that the most pronounced declines were in men aged 40 and older and women 60 and over.

For more information, check out http://www.cdc.gov/nchs.