A new study suggests that smoking causes 14 million major medical conditions in the United States. The number is alarming, as it is 9 percent higher than the estimate of the U.S. Centers for Disease Control and Prevention (CDC) 10 years ago.

Study leader Brian Rostron from the Center for Tobacco Products at the U.S. Food and Drug Administration worked with his colleagues in analyzing the data of the 2009 U.S. Census Bureau and a national survey conducted from 2006 to 2012.

The analysis revealed that 7 million people have a total of 11 million primary medical conditions caused by smoking. Half of the senior-aged respondents reported at least one smoking-related illness. The number was raised to 14 million to include unreported cases.

"That's obviously an immense number," Rostron told Reuters Health in a phone interview. "It's continuing to be a problem. Even if people are former smokers, they have lasting lung damage."

Chronic obstructive pulmonary disease (COPD) tops the list of the most common medical conditions reported, with 4.3 million cases, followed by heart attacks, diabetes, strokes and cancers. The researchers were surprised that the cancer linked to smoking is not related on lungs alone, as some of the respondents were diagnosed with cancer of internal organs near the lungs.

"The implication is that smoking causes more harm than we previously thought, much of it in chronic pulmonary obstructive disease," Dr. Steven Schroeder, a professor of medicine at University of California, San Francisco and head of its Smoking Cessation Leadership Center, told Healthday News. "When you think about how smoking hurts you, people usually think about deaths first, and then those who are sick. There is much more lifetime illness related to smoking."

The study also showed that smoking-related illnesses were almost the same between men and women, despite the knowledge that fewer women smoke. Researchers believe that women became vulnerable due to second-hand smoke.

The researchers believe that there is hope yet in lowering these numbers, as smoking is not a permanent habit. They encourage smokers to seek help to quit smoking effectively once and for all.

The study was published in the Oct. 13 issue of JAMA Internal Medicine.