The Centers for Disease Control and the National Cancer Institute recently released a study that found that being modestly overweight is possibly helpful for long life, while being underweight can shorten your life.
Flegal discovered that being overweight (BMI’s of 25-30) was not responsible for increased mortality. In fact for CVD, cancer and all other causes, being overweight actually increased one’s chance of living longer. In total, overweight was associated with a total of 138, 281 fewer deaths. Being overweight is not likely to kill you.
She found that being obese increased the risk of premature death for the most part in only the most obese, that is those with BMI’s over 35. In other words, even modest obesity is not a death sentence. For example, those with BMI’s of 30-35 aged 25-69 did not have a statistically significant increased risk of dying from cardiovascular disease. Indeed, for cancer the results are even more startling since even those with BMI’s in excess of 35 did not have a statistically significant increased risk of dying. And for all other diseases other than CVD and cancer, obesity up to a BMI of 35 was modestly protective — that is, likely to result in a longer rather than a shorter life.
She also found that being underweight carries substantial risks. Whereas obesity accounts for 95, 442 deaths, being thin is associated with 46, 398 — almost half as many deaths as obesity. But then one is unlikely to ever hear about the risks of being thin or the mortality toll associated with underweight.
Nor are these findings a fluke. In 2005 Flegal and the same team found that being overweight reduced one’s chances of dying, that the majority of deaths due to obesity were in the morbidly obese, and perhaps most surprisingly, that there was no statistically significant increased risk for death associated with even modest obesity.