New York City residents are growing obese at a rate nearly three times that of other Americans, prompting some who cited a link between weight gain and smoking cessation to question whether the city’s crackdown on smoking may have had an unexpected result.

In a new study, city health officials found that obesity and diabetes rates here increased 17% between 2002 and 2004. By contrast, there was a 6% increase in national obesity rates during that time, and no significant increase in the rate of diabetes. City residents also gained 10 million pounds collectively during the two-year period, researchers found. The findings were reported in the April issue of the journal Preventing Chronic Disease.

While public health officials said the findings underscored the need for disease prevention programs, others drew a correlation between the rising obesity rate and a smoking ban that took effect in the city’s bars and restaurants in 2003. According to city health officials, about 240,000 New Yorkers quit smoking since the agency launched a comprehensive antismoking campaign in 2002.

Weight gain among individuals who quit smoking has been well documented. According to one study that evaluated weight gain after smoking cessation, researchers found the risk of weight gain is highest during the two years after a person quits. The study, published in 1998 in the Journal of Family Practice, found that on average, those who quit gain between 11 and 13 pounds.

“What you see on the micro level of your friends gaining weight after they quit smoking has to also have an effect on the macro level,” a senior fellow at the Manhattan Institute, Walter Olson, said. “Yes, it probably is true that one of the reasons America is gaining weight is because of tobacco going out.” He said the ban was probably “one factor among many” contributing to the high obesity rates here.

Critics of the ban took a harder stand. “While they’re trying to save one segment of society… they’re getting nowhere because it has a negative effect elsewhere,” the founder of Citizens Lobbying Against Smoker Harassment, Audrey Silk, said.

City health and mental hygiene officials acknowledged the timing but said they had no evidence that the crackdown on smoking had caused obesity rates to increase. Instead, the study’s authors pointed to the city’s demographic makeup and cited New York’s large population of high-risk individuals, including blacks and Hispanics and those living in poverty. In a related study, also released yesterday, health officials blamed soda consumption for the city’s obesity rates. About 27% of adults drink one or more sodas daily, researchers found. Nationwide, 34% of Americans — or 72 million individuals — are obese and about 7% of the population has diabetes.

In New York City, more than 1.7 million city residents are obese and about 700,000 have diabetes. According to the study, the obesity rate in 2004 climbed to 22.8%, up from 19.5% two years earlier. During the same two-year period, the diabetes rate increased to 9.5% from 8.1%. In raw numbers, researchers found, about 173,500 adults in New York City became obese and 73,600 developed diabetes between 2002 and 2004. New Yorkers are less likely to be obese than the rest of America, but they are more diabetes prone. While the increases were not limited to one neighborhood, the report found that among Hispanics, the obesity rate grew 14%, to 26.2% in 2004, up from 22.9% in 2002.

The rate also increased among the city’s immigrants, who previously had lower rates of obesity and diabetes. Among foreign-born New Yorkers, the obesity rate increased 33% to 22.4% in 2004, up from 16.8% in 2002.

“The problem is, we have seen increases in these very large groups,” the health department’s director of research, evaluation, and planning, Gretchen Van Wye, said. She said the largest increases occurred among the fastest-growing populations. Ultimately, both conditions would become even more “pervasive,” she said.

New York City doctors treating diabetic patients said the disease already is widespread.

Earlier this week, Lighthouse International opened a diabetes center to help patients adapt to diabetes-related vision loss. According to Lighthouse’s president and CEO, Tara Cortes, diabetes causes about 25,000 new cases of blindness annually nationwide. “Vision loss is one of the side effects of diabetes that a lot of people don’t think about,” she said. “It affects probably half of people with diabetes.”

Last week, the Naomi Berrie Diabetes Center at Columbia University Medical Center received a $21 million gift from the Russell Berrie Foundation earmarked for research and patient care.

Yesterday, a physician there, Dr. Lauren Golden, said even those without diabetes should be mindful of risk factors, including a sedentary lifestyle and obesity. “Nobody is immune from this,” she said.