They come in uninsured and often with infectious diseases. But, because new immigrants are generally younger than natives, on a per capita basis they utilize 55 percent less health care ($1,139 vs. $2,546 per capita). This was the conclusion of Dr. Sarita A. Mohanty  of USC [send her email]  in a study she did for the express purpose of making immigrant health care costs look good.

However, thereafter things get worse, not for the first time in the immigration debate. Long-term exposure to U.S. culture appears to be dangerous to immigrant health, and to the health of their U.S.-born children. Result: Immigration-imported health care costs are a ticking time bomb.

Obesity: Some 8 percent of immigrants who have lived here for less than a year are obese. But this jumps to 19 percent among those who have been here for at least 15 years. [Obesity Among US Immigrant Subgroups by Duration of Residence, Journal of the American Medical Association]

(The figures are adjusted for the increased age of the immigrant over that time.) These trends "may reflect acculturation and adoption of the U.S. lifestyle, such as increased sedentary behavior and poor dietary patterns. They may also be a response to the physical environment of the United States, with increased availability of calorically dense foods and higher reliance on labor-saving technologies, " according to the Associated Press. [Immigrants fatten up after years in U.S. By Lindsey Tanner  December 15, 2004]

Our Super-size-me culture is not the only culprit, however: "For example, there is some evidence that Latina women in general (regardless of immigration status) may have a higher threshold than Whites for their definition of, and concern about, overweight. Some immigrant populations may view weight gain as a sigh of good health," according to a public health study done at the University of Chicago.[Namratha R. Kandula, et al., "Assuring the Health of Immigrants: What the Leading Health Indicators Tell Us," Annual Review of Public Health, April 2004]

Treating an obese person cost $1,244 more than treating a normal weight individual in 2002 (the latest year of available data).

Diabetes: Obesity increases the risk of acquiring diabetes—especially for certain immigrant groups: Latinos, particularly Mexican-Americans, incur diabetes at close to twice the rate of whites. Nor are Asians immune:

"Asians, especially those from Far Eastern nations like China. Korea, and Japan, are acutely susceptible to Type 2 diabetes, the most common form of the disease…They develop it at far lower weights than people of other races, studies show; at any weight they are 60 percent more likely to get the disease than whites." [East Meets West, Adding Pounds and Peril, NY Times, January 12, 2006]

The cost of treating someone with diabetes in the U.S. is two to three times the cost of treating someone without that condition.

Mental health: Immigrants appear to have lower rates of mental illness than natives—but many studies find that second and third generation immigrants are at higher risk for psychological distress. This result may simply reflect underdiagnosis in first generation individuals due to the stigma associated with such problems in immigrant cultures, as well as linguistic barriers.

Injuries and violence: We have documented the above average propensity of U.S.-born Hispanics to die in automobile accidents and in the workplace. Similar risks are found with pedestrian injuries and deaths (twice as likely to kill Hispanic than non-Hispanic white children), homicides, and violence against family members.  

Immunizations: Foreign-born children are estimated to be almost 45 percent less likely to be immunized for diphtheria, pertussis, tetanus, influenza and Hepatitis B. Since the late 1990s, most confirmed cases of congenital rubella have occurred in children of foreign-born rather than U.S.-born mothers.

Because of their sheer numbers, immigrants are already responsible for a disproportionate share of the annual rise in health spending. From 2000 to 2004, the immigrant stock (immigrants and their children) accounted for about 62 percent of U.S. population growth—and about 45 percent of the increase in health spending.

This will inexorably increase.

Edwin S. Rubenstein (email him) is President of ESR Research Economic Consultants in Indianapolis.