- Researchers report that people with obesity are more likely to develop depression and poor feelings of well-being than those without obesity, independent of lifestyle factors and disease.
- They note that people with obesity many times have to deal with prejudice and social stigma that can affect their mental health.
- The researchers added the association between obesity and depression was stronger in women than in men.
Obesity is associated with poorer mental health, including depression and a poor sense of well-being, according to a study published today in the journal PLOS ONE.
Researchers at the School of Public Health at the University College Cork in Ireland added that lifestyle factors don’t appear to have an impact on these mental health issues.
In their study, the researchers examined the medical records of 1,821 men and women between the ages of 46 and 73 randomly selected from a large primary care center.
They looked at the relationship between mental health scores and obesity using body mass index (BMI) and waist/height ratios while adjusting for lifestyle factors and disease conditions.
The scientists used the 20-item Center for Epidemiologic Studies Depression Scale and the World Health Organization’s Five Well-Being Index.
Before the study began, participants completed an overnight fast and provided blood samples for fasting glucose and glycated hemoglobin. Researchers measured height, weight, and waist circumference as well as calculating BMI.
The participants completed a general health and lifestyle questionnaire. The scientists used this information to assess demographics, lifestyle behaviors, and the presence of other diseases.
In their findings, the researchers reported that BMI and waist/height ratios that signaled obesity were associated with an increase in depression and lower well-being.
They added that the relationship between obesity and depression was significantly higher in women than in men.
The researchers noted that their results were consistent with previous research.
They said that obesity is also interrelated with social and physical factors. For example, they noted, extra weight can invoke prejudice, discrimination, and social stigma. It can also lead to physical symptoms, such as joint pain, back pain, and fibromyalgia.
Experts say these social and physical effects of obesity can lead to depressive symptoms.
“There is a biological link between obesity and depression,” said Eva Panigrahi, PhD, a psychologist at The Ohio State University Wexner Medical Center, who wasn’t involved in the study. “Obesity may contribute to an environment that can lead to chronic physiological and neurological outcomes, including diabetes, cardiovascular disease, severity of depression, gene-environment interactions, adverse childhood experiences, eating and physical activity, and stress.”
“The relationship between obesity and depression can be explained as a vicious, mutually strengthening cycle that includes negative physiological and psychopathology factors,” Panigrahi told Medical News Today.
The researchers suggested that targeted interventions for reducing depression should include better weight management at the population level.
The medical community has linked depression and obesity for a long time, according to Dr. Mir Ali, a bariatric surgeon and medical director of MemorialCare Surgical Weight Loss Center at Orange Coast Medical Center in California.
“This study defines the connection further. Although, it isn’t surprising,” Ali, who was not involved in the study, told Medical News Today. “Obesity affects every organ and the brain is an organ. Depression has many causes and biology is one of them.”
“It’s hard to say whether obesity causes depression or depression contributes to obesity,” Ali added. “My patients tell me they are consistently discriminated against because of their weight. Despite the knowledge we have gained about obesity, there is still social stigma surrounding it.”
Examples of discrimination and prejudice against people with obesity, according to the National Council on Aging, include:
- People with obesity are lazy and irresponsible and lack willpower and self-discipline.
- People with obesity have only themselves to blame.
- Larger body size is undesirable.
- People with obesity are not very smart and less capable of succeeding.
- People with extra weight have poor hygiene.
Social stigmas can result in serious social, psychological, and physical effects, including depression.
“There is growing research on the perfection of antidepressant medication management that does not stimulate eating and weight gain,” Panigrahi said.
“There are few antidepressants that are associated with weight loss (i.e., bupropion). In conjunction with medication management, incorporating evidenced-based psychotherapy is considered a gold standard treatment for depression,” she added.
“Evidenced-based psychotherapy such as cognitive behavioral therapy (CBT) has demonstrated to be an effective approach for depression and weight,” she said.
The major strengths of the study include:
- The researchers used validated depression and well-being scales.
- They used two indexes to measure adiposity.
- There was equal representation by sex.
The study’s major limitation is that all participants came from a single primary care center and the majority were European-Caucasian. The results may not be representative of the general population.
Panigrahi points out an additional limitation.
“The authors incorporated a cross-sectional design, which inevitably limits the ability of deriving causal relationships,” she said.
According to the National Institutes of Health, a cross-sectional design is an observational study that collects the end data for all participants at one point in time.
