People live longer because they live healthier lives than the rest of us—smoking and drinking less, and exercising longer. Right?

Nope.

Researchers at Albert Einstein College of Medicine of Yeshiva University asked 477 Ashkenazi Jews over the age of 95 who were living on their own about their lifestyles and habits at age 70. They chose Ashkenazi Jews because this group was descended from a small founder group, and therefore had fewer genetic variations than many other ethnic groups. They compared their answers to those of 3,164 people born around the same time in the general population who were interviewed in the early 1970s.

The conclusion: Those approaching their 100th birthday were similar to the general population in terms of body-mass index, smoking, alcohol use and diet. And the older males actually exercised less than those in the comparison group.

However, there was one striking difference: Although older people were just as likely as the control group to be overweight, they were less likely to be obese, generally defined as having a body mass index of 30 or higher. Only 4.5% of the older men and 9.6% of the older women were obese, compared to 12.1% of the men and 16.2% of the women in the general population. A 2007 federal study found that about one-third of all American adults are obese, increasing the risks of high blood pressure, Type 2 diabetes, stroke, heart disease and osteoarthritis.


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The researchers also asked their elderly subjects why they thought they had lived so long. One-third said that long life ran in their families; about one on five attributed it to exercise and an equal number to a positive attitude. Other reasons mentioned included a busy or active life (12%); less smoking and drinking (15%); good luck (8%) and religion or spirituality (6%).

Lead researcher Nir Barzalai said in a news release that the findings don't suggest that people need not pay attention to healthy habits, which do help prolong life, as well as its quality. Rather, he says, those who live a long time despite unhealthy indulgences may simply have "longevity genes" that help buffer their negative effects.