The negative impact of obesity on one's health has been a subject of concern for a while now. Several studies have found a link between obesity and risk of health complications such as stroke, heart attack, type 2 diabetes, and cancer to name a few.
Previous studies have suggested that being overweight can lead to premature deaths. Now, a new research conducted by the Boston University School of Public Health and the Harvard T.H. Chan School of Public Health reaffirms the assertions.
The study from BUSPH and Harvard T.H. Chan reveals that being even slightly overweight can decrease the life span of an individual.
This research also shares its reservations pertaining to the "obesity paradox" theory. This hypothesis stated that an overweight person who is not obese lived longer when compared to their slimmer counterparts. The "obesity paradox" asserted that mild obesity did not increase the risk of death in overweight individuals.
Can Being Slightly Overweight Up Death Risk?
To conduct the study, the researchers collected and analyzed the weight history of 225,072 men and women. The participants were examined on the basis of their body weight, physical activity, diet, smoking habit, as well as health issues.
To calculate the body mass index, or BMI, the researchers used the 16-year weight history of the participants. The participants were tracked for 12 years. However, at the beginning of the 12-year follow-up period, the participants were either 50 years or 60 years old.
During the follow-up period, deaths of 32,571 participants were observed. The researchers found that individuals with the highest BMI of 25.0 to 29.9 were 6 percent more prone to die during the follow-up period.
The participants who recorded the maximum BMI under the normal weight range of 18.5 to 24.9 were less likely to die early.
The researchers noticed that those in the obese range (having a maximum BMI ranging between 30 to 34.9) or severely obese range (above 35 BMI) were 24 percent to 70 percent more likely to die when compared to those falling in the normal weight category.
This finding suggests that individuals who are slightly overweight may have a decreased life span vis-à-vis their slimmer counterparts.
Why The New Study Is Better Than Previous Ones
Researchers have criticized previous studies that supported the "obesity paradox" for the manner in which they were conducted.
"Prior studies showing an association between overweight people and lower mortality carried the risk of reverse causation bias - in other words, the conditions leading to death are what might have caused the lower BMI, rather than the lower BMI causing death," shared Andrew Strokes, the study's senior author.
Roughly a third of U.S. adults deal with weight issues, and over a quarter of the world's population is overweight. Therefore, the researchers assert that the heightened death risk in overweight and obese people is "important from a public health perspective."
The study has been published in the journal Annals of Internal Medicine.