The link between depression and genetic variants connected to higher body mass index suggests that obesity causes depression

People who are obese are more possible to possess depression than those who aren't, however it’s been unclear how one may cause the other. A study of the link between depression and genetic variants connected to higher body mass index suggests that obesity causes depression, and that it is the untoward psychological effects associated with obesity that drive the mood disorder. “These new findings are maybe the strongest up to now to counsel higher weights may actually contribute to depression,” Naveed Sattar, a professor of cardiovascular and medical sciences at the University of Glasgow who didn't participate within the work, tells The Guardian. “Of course, several alternative factors will cause depression, but, even so, weight loss may well be useful to boost mental state in some people, whereas keeping leaner normally should facilitate reduce probabilities of depression.”

To determine the direction of relation, researchers at the University of Exeter and the University of South Australia examined genetic information from the United Kingdom Biobank together with 48,791 people with depression and 291,995 without. They used genetic predisposition to the next body mass index (BMI) as a proxy for actual BMI (which they additionally had information on) to disentangle BMI and its relationship to depression from alternative factors that might confound the results.

The authors checked out 2 sorts of genetic variants and their relationship to depression: those who are related to higher BMI and conjointly joined to metabolic issues, like diabetes, and those that are joined to higher BMI however also are tied to a lower risk of metabolic issues. The researchers reasoned that if it were health problems attendant with fatness that were creating individuals depressed, instead of fatness itself, the genetic variants that didn’t carry any metabolic baggage wouldn't be related to depression. However, what they found was that the genetic variants joined with a lower metabolic risk conjointly correlate with depression.