Being overweight doesn't increase risk of dying
A study from Germany shows that being overweight does not increase risk of dying. Most studies link being overweight and obese to increased mortality, but the new study suggests that just being overweight, versus being obese, needs more study. The finding that being overweight does not increase risk of dying was examined in the German population.
According to the findings, most Germans are overweight, with increased body mass index (BMI) between 25 and 29.9 kg/m2. The study authors systematically reviewed 42 studies, examining the relationship between weight and risk of disease and death. They found that being overweight does not increase risk of dying – but obesity leads to a twenty percent increase in mortality.
The study also found that with aging, obesity has less impact. In fact, the study authors found that overweight men have a seven percent lower death rate. Higher body mass index was also associated with decreased bone and hip fractures.
Heart disease risk for being overweight was found to be increased by twenty percent, but in the presence of obesity, the risk jumped to fifty percent in both men and women. No relationship to stroke was found from either being overweight or obese.
Women who were overweight were not found to be at increased risk of dying, but men had a ten percent increase in mortality.
The authors write, “Interpreting these results is challenging. According to the analyses performed by the authors, all cause mortality is not increased in overweight. On the other hand, the mortality risks for several diseases are increased while they are reduced or unchanged for others. In obesity, all cause mortality is about 20% higher than in normal weight individuals. In morbid obesity, all cause mortality can be more than 200% higher. Whether a role is played by fat distribution patterns (WC and WHR) and what this role may be remains essentially unknown due to insufficient data”.
The review did support the risk of developing type 2 diabetes – the chances of diabetes increased “by about 20% for each 1 kg/m2 rise in the BMI”. When BMI reaches 29.2, diabetes risk increases by one hundred percent. However, the overall death rate from cancer among extremely obese men (BMI above 40) is no higher than among those of normal weight.
The study is somewhat confusing, given all we have learned so far about being overweight or obese increasing our risk of dying from disease. The study is based on cohort analysis only, but does raise questions about weight loss goals.
The authors concluded, “The assumption that overweight versus normal weight is associated with an increased morbidity and mortality risk must be stated more specifically.” According to this study, being overweight does not increase risk of dying. The authors suggest that more studies are needed to clearly define health risks associated with risk of death from being overweight versus being obese.