Trends in weight-related morbidity and mortality are the focus of 2
articles in this issue of JAMA. First, Flegal and
colleaguesArticle used nationally representative data from
NHANES I, II, and III and follow-up data collected through 2000 to estimate
the number of excess deaths in 2000 associated with body mass index (BMI),
categorized as underweight, normal weight, and obese. They found that compared
with normal weight, both underweight and obesity were associated with increased
mortality, and the risk associated with obesity declined over time. In the
second article describing 40-year trends in cardiovascular disease risk factors
by BMI categories, Gregg and colleaguesArticle report that
the prevalence of high cholesterol levels, hypertension, and current smoking
have declined, particularly among overweight and obese persons. Diabetes was
the only risk factor found to have a stable prevalence over the 40 years.
In an editorial,Article Mark discusses challenges in assessing
obesity-related health risks.