Obesity is tied to mental health disorders, but the correlation is complex. Here’s what you need to know about the link between body weight, depression, and anxiety.

It can be difficult to cope with anxiety and depression, but your body weight isn’t the only determinant of mental health conditions you may experience. All bodies are different.

According to the Centers for Disease Control and Prevention (CDC), about 42 % of the U.S. population has obesity. The National Alliance on Mental Illness reports that 1 in 5 adults in the United States experiences mental illness each year.

While experts are still trying to determine exactly how these common disorders are connected, they know that a link exists, and millions of Americans are affected. Understanding how mental health and body weight are linked may help you better advocate for your health needs.

Research has shown obesity is associated with approximately 25 % increased risk of developing mood and anxiety disorders. But more research is needed because this study doesn’t show whether obesity causes these disorders or vice versa.

Obesity is defined as having a body mass index (BMI), a measure of body fat based on height and weight, of 30 or higher. But it’s suggested not to solely use this tool to determine health conditions or treatment options.

According to a 2015 study, BMI has limitations when determining body fat mass.

Experts suggest that worrying about weight gain or harboring negative feelings about one’s image can cause anxiety.

A large study from 2017 consisting of high school students suggested body image dissatisfaction is concurrent with symptoms of anxiety disorders, such as:

Anxiety is associated with increased activity in a part of the brain known as the hypothalamic-pituitary-adrenal (HPA) axis. A 2009 animal study suggests that a person’s appetite can increase when the HPA axis doesn’t function properly, which may lead to weight gain.

A 2021 animal study published in Molecular Psychiatry also uncovered insights into the link between obesity and mental health.

Researchers found that a neural circuit in the brain that regulates mood and appetite may be a key target for both conditions. When they gave mice a combination of two drugs that act on this circuit, the animals experienced less anxiety and lost weight.

Some symptoms of anxiety may include:

  • feelings of worry or dread that interfere with everyday life
  • feeling restless, irritable, on-edge, or anxious
  • problems concentrating
  • fatigue
  • difficulties falling asleep or staying asleep
  • unexplained headaches, stomachaches, or other types of pain

According to the Center for Disease Control and Prevention (CDC), about 43% of adults with depression from 2005-2010 had obesity. Adults diagnosed with depression are more likely to be obese than those without the disorder.

Research has also suggested an inverse relationship between depression and obesity. According to a large 2014 study, depression has a higher prevalence in people with obesity or underweight.

Though the exact reasons for this association aren’t known, genetic, social, and environmental factors are likely at play. Additionally, antidepressant medications used to treat depression may trigger weight gain in some individuals.

Depression can foster low energy, possibly leading to less physical activity and, ultimately, weight gain.

Common signs of depression may include:

  • severe or persistent sadness
  • feelings of hopelessness, worthlessness, guilt, irritability, or negativity
  • loss of interest in activities that were once enjoyable
  • fatigue
  • difficulty concentrating
  • memory issues
  • trouble sleeping
  • weight changes
  • thoughts of suicide or death
  • unexplained headaches, stomachaches, or other types of pain

Are you currently in crisis?

If you feel like you’re having a mental health emergency, you can:

If you decide to call an emergency number like 911, ask the operator to send someone trained in mental health, like Crisis Intervention Training (CIT) officers.

Taking care of your body, both physically and mentally, can help improve your overall health and help you feel better.

Consider the following tips to nurture yourself:

  • Get active: Regular exercise can help with depression and boost your mood. Whether you move for 15 minutes a day or an hour, try to engage in activities that feel good to your body.
  • Eat plenty of produce: Consider eating fruits and veggies which contain essential vitamins, minerals, and phytonutrients to keep you healthy.
  • Stay hydrated: Drinking more water throughout your day may improve your mental health. A 2014 study indicates that daily low water intake is associated with decreased calmness, satisfaction and positive emotions.
  • Connect with others: A strong social support network lowers stress levels in some people.
  • Keep a gratitude journal: Daily gratitude exercises can help you control your mood.
  • Try meditation: Meditation and relaxation practices may help improve your physical and mental well-being.
  • Soak in some nature: Nature can help lessen symptoms of depression and boost energy.
  • Consider professional help: Talking to a mental health expert can help you recognize your triggers and implement useful strategies.

There’s a clear connection between obesity and mental health disorders. People with high BMI are more likely to experience depression and anxiety. Conversely, those with mental health conditions are at risk for obesity.

Researchers are looking for more answers to explain this correlation, but it’s likely a result of several overlapping factors.

If you have either condition, lifestyle changes and medical treatments may boost your mood. Consider talking with your doctor about the best techniques for your situation.