One article is a review of 40 earlier obesity studies that included 250,000 people over a period of about four years. This review, from the Mayo Clinic, found that underweight people were at the greatest risk for overall death from any cause and for death from heart disease.
Overweight people (those with a body mass index [BMI] between 25 and 29.9) had the lowest risk of overall death and death from heart disease. Most surprising is the finding that obese people (BMI 30-35) had no greater death risk - whether from any cause or from heart disease - than people of ideal body weight. Even the most obese people had no higher overall risk of death, though they had the highest risk of death from heart disease.
The second study is a six-year follow-up of 6,600 men and women 75 years of age or older in Britain. Their data showed that a higher risk of death - overall and from heart disease - was more clearly related to a large waist circumference than to a high BMI.
The third study, from the National Institutes of Health, is a follow-up for up to 10 years of deaths among 530,000 men and women in the U.S. It found that being overweight or obese in midlife (around age 50) was associated with a higher risk of overall death. In addition, the risk was particularly great in younger men and women with no evident health problems and who had never smoked.
What should we do about these conflicting findings? Should we all throw away our scales and eat as much as we want? I don't think so.
No matter what these and other studies show, I am convinced that excessive weight is a ticket for a heart attack, diabetes, and a shorter life. Most people know if they are overweight, and most doctors can tell when their patients weigh too much. (If you know your height and weight but don't know your BMI, this online calculator can tell you what it is. I consider that any weight gained after about age 20 is excessive and almost all fat. BMI is not a perfect measure of the risks of excess weight, and doctors should routinely be measuring their patient's waists, too.
Maybe it's time to declare a moratorium on any more studies that just muddy the waters.
I think the most important questions about the dangers of obesity are already answered. Many studies already show the ill effects of obesity that can worsen quality of life - from limitations to daily activity due to shortness of breath and arthritis of the knees and hips, to back pain from carrying extra weight, to social stigma and discrimination. There's no need for more of these studies, either.
