Researchers from various medical establishements across the States noted that while the prevalence of obesity has increased substantially in the US since the 1980s, little is known about the obesity rate within this subsection of society. Immigrants, moreover, are the fastest growing segment of the US population.
Led by Mita Sanghavi Goel, the scientists set out to estimate the prevalence of obesity among immigrants, looking at how long people had been in the States, their diet, exercise regime and country of origin.
The researchers found that the prevalence of obesity was 16 percent among immigrants and 22 percent among US-born individuals. However, there was a significant increase in the likelihood of an individual being obese if he/she had lived in the US for more than 15 years.
"The age- and sex-adjusted prevalence of obesity was 8 percent among immigrants living in the United States for less than one year, but 19 percent among those living in the United States for at least 15 years," said the scientists (JAMA 2004;292:2860-2867).
They added that after adjusting for age, sociodemographic, and lifestyle factors, living in the US for 10 to 15 and at least 15 years was associated with BMI increases of 0.88 and 1.39, respectively.
"The association for 15 years or more was significant for all immigrant subgroups except foreign-born blacks," added the researchers.
Additionally, immigrants were less likely than US-born individuals to report discussing diet and exercise with clinicians.
Indeed, according to a recent survey by the Calorie Control Council, more Americans are on a diet now that at any time in the last 15 years with 33 percent of Americans or 71 million people are currently on a diet.