The latest surgeon general’s report on the health effects of smoking — issued at the 50th anniversary of the pathbreaking 1964 report — offers astonishing new evidence of just how much harm tobacco is causing. Despite the many gains in reducing risks over the past half-century, researchers keep finding new and insidious ways in which smoking is harming the smokers themselves and nonsmokers who breathe in toxic fumes.

The report, issued last Friday, finds that cigarette smoking kills even more Americans than previously estimated (about 480,000 a year, up from 443,000), and is a cause, though not necessarily the major cause, of even more diseases than previously recognized, including liver and colorectal cancers. These add to the long list of other cancers caused by smoking, as well as rheumatoid arthritis and other ailments. The report newly identifies exposure to secondhand smoke as a cause of strokes.

The report estimates that smoking costs the United States between $289 billion and $333 billion a year for medical care and lost productivity, well above the previous estimate of $193 billion.

Most shocking, the report finds that today’s smokers have a much higher risk for lung cancer and chronic obstructive pulmonary disease than smokers in 1964, despite smoking fewer cigarettes.