How Depression and Obesity Are Linked

A person who lives with obesity may very well also have depression. Obesity is a risk factor for an elevated risk of depression, research shows, increasing its odds by 33%. As rates of obesity rise—and as stigma about both conditions persists—depression is likely to become more common.

And, it turns out, the reverse may also be true: Depression may be responsible for obesity, with observational studies suggesting that depression might increase a person’s body mass index (BMI), which often is used to diagnose obesity.

Grownups aren’t the only segment of the population at risk for these conditions. Living with obesity as a teenager may be linked with later depression in young adulthood, according to one long-term study of more than 8,000 people.

“Obesity and depression often occur together,” says Uma Naidoo, M.D., a Harvard-trained nutritional psychiatrist, professional chef, and nutritional biologist. “There is a strong connection between the two.”

“People who are obese develop depression at higher rates than people without depression, and people with depression tend to have obesity at higher rates than those without depression,” says Kelly Allison, Ph.D., director of the Center for Weight and Eating Disorders at the Perelman School of Medicine at the University of Pennsylvania.

Allison says depression can lead to emotional eating, binging on food, and excessive nighttime eating, all of which can contribute to obesity.

Depression contributes to obesity in other ways, too, explains George Alvarado, M.D., medical director of behavioral health at Northwell Health Solutions in Manhasset, New York. One key symptom of depression that can result in obesity can be a change in appetite, especially the tendency to overeat, Dr. Alvarado says.

“Also, a decrease in energy and motivation, typically experienced in depression, can lead to a decline in self-care, in particular healthy diet and exercise habits,” he says.

Stress

Depression and anxiety can be implicated in the development of obesity because they can cause a rise in stress hormones like cortisol, Allison says.

“And this rise in stress hormones can lead to an accumulation of fat in the stomach, which is the least healthy place to have excess fat,” she explains.

Poor sleep also leads to elevated cortisol; therefore sleep quality is also a factor in obesity for children and adults.

Genes

There is also a sizable genetic risk for obesity, she says. Estimates of this risk range from 40% to 70%, research shows. So if someone in your family has obesity, you may have a 40% to 70% risk of it yourself.

Some health conditions—such as Prader-Willi Syndrome, Cushing’s syndrome, and polycystic ovary syndrome (PCOS)—as well as taking certain medications, like steroids and antidepressants, can also lead to obesity.

Poor diet

Changes such as an imbalance in your gut microbiome (the trillions of bacteria that help your gut thrive) can result in obesity, Dr. Naidoo explains. (She is the author of This is Your Brain on Food and the forthcoming Calm Your Mind with Food.) These harmful changes can be due to eating highly refined and processed foods, Dr. Naidoo says. At the same time, consuming these foods may trigger anxiety or depression, she says.

Environment

Unfortunately, not all of us have access to healthy food and safe places to exercise. The National Institute of Child Health and Human Development acknowledges that living in places without green spaces, sidewalks, and nearby supermarkets, and where gyms or nutritious food and drink choices are unaffordable, contribute to obesity.

“We are fortunate to be at a turning point for treating obesity,” Allison says. There are now behavioral weight loss programs that produce a 5% to 10% weight loss, and bariatric surgery can result in anywhere from a 25% to a 35% reduction in a person’s weight, she says.

Semaglutide (branded Wegovy for obesity treatment, Ozempic for type 2 diabetes treatment), at one time only used to improve blood sugar control, was approved in 2021 to treat obesity. Similar diabetes drugs, such as tirzepatide (Mounjaro), are expected to be approved to treat obesity as well.

“These are better than medications we have had in the past with regards to overall weight loss and safety,” Allison says.

Other FDA-approved weight loss medications include liraglutide (Saxenda), phentermine-topiramate (Qsymia), orlistat (Xenical, Alli), and naltrexone-bupropion (Contrave).

In 2023 the American Academy of Pediatrics updated its guidelines on childhood obesity treatment for the first time in 15 years. In short, it now recommends certain weight-loss drugs for children as young as 12 and establishes some situations where bariatric surgery may be beneficial for kids and teens. These treatments are in addition to lifestyle-change recommendations like eating healthy and moving more.

But besides medications, behavioral weight loss programs, and surgery, attitudes about body size need to change, says Meenakshi Suman, M.D., a psychiatrist at Sheppard Pratt, a mental health facility in Baltimore.

“Society needs to work on accepting that all bodies are unique and deserve to be celebrated,” Dr. Suman says. “Our focus should be more about lifestyle that improves functioning than any weight-related yardsticks.”

And though there are several methods available now to treat obesity, they all have certain risks and varying rates of success. The best treatment for obesity—and likely the one your physician will recommend first—is incorporating more heart-healthy foods into your diet, limiting sugary and processed food and drinks, increasing your physical activity, and getting enough quality sleep.

A person may be prone to depression because of an imbalance of neurotransmitters in the brain, says Allison. In other instances, there can be triggering situations.

“For people with obesity, this may be related to experiencing ‘fat bias’ in interactions at work, or with their medical providers, or in their relationships,” Allison says. “Depression also can be triggered by being limited in some way by their size, including difficulty shopping for clothes that fit, not being able to fly in an airplane comfortably or go on rides at an amusement park.”

Low self-esteem triggered by body dissatisfaction can be a cause for depression, she says.

“And once someone is feeling depressed, it becomes difficult to go out and experience new interactions with others that might help break the negative mood that someone is in,” Allison says.

Diet may also be a contributing factor when it comes to depression, Dr. Naidoo says.

“A high intake of processed and refined foods is linked to worse mental health symptoms,” she says.

When a team of researchers in 2018-19 looked at the factors for depression in more than 112,000 older British adults, they found certain ones that increased the chances of depression. Among the factors that had the highest association of depression were daytime napping; how much time people spent using the computer, watching TV, or using a cell phone; and eating a healthy diet inconsistently.

One of the most effective treatments for a depressive disorder is cognitive behavioral therapy (CBT), Allison says.

“CBT teaches people how to identify the ways that their thoughts and feelings in difficult situations impact our decisions about how we evaluate ourselves, and how we end up behaving to keep us in our old ways of behaving and thinking negatively about ourselves,” she says.

A variety of medications are available, too, and medications tailored to the individual needs of a person can be very effective at treating depression, says Dr. Suman. Medication can be especially helpful for people who have moderate to severe symptoms of depression, says Dr. Alvarado.

How and what you eat may also influence your mood, Dr. Naidoo says.

“Making the effort to eat more healthy whole foods can be a powerful move toward supporting mental and metabolic health,” she says. “Adhering to a whole-foods, plant-predominant diet like the Mediterranean diet may improve one’s mental health and result in fewer depressive symptoms.”

In addition to a healthy diet, getting enough sleep and enough physical activity can help protect against depression, too.

Children who live with obesity can also experience depression.

There’s a host of treatments for children, Dr. Suman says. But the goal, he says, should be more about helping people make small changes like eating the right foods and incorporating more activity into their lives and less about a focus just on weight.