Depression and Physical Health: What’s the Link?

By Martha McLaughlin

Depression is very common, affecting 6.7 percent of adults in the United States and 12.8 percent of adolescents.¹ Unfortunately, about 85 percent of people suffering from major depression also deal with at least one chronic physical health condition.² In some cases, the conditions spring from a single, shared cause, and in others, one issue contributes to the development of the other.

Shared Causes

Among the possible factors contributing to both depression and physical complaints are nutritional deficiencies and dietary imbalances. One study found that the most common deficiencies found in people suffering mental health challenges were omega–3 fatty acids, amino acids, minerals and B vitamins.³ Harvard Health notes that diets high in red and processed meat, sweets, refined grains and high-fat dairy are associated with an increased risk of developing depression.⁴ Similar diets are associated with a range of possible physical problems as well.

Prolonged stress is another potential issue. The body responds to stress by altering levels of various hormones and neurotransmitters, which can provide needed energy. If the stress continues, however, these chemical changes can imbalance the body and lead to both physical and mental challenges. Imbalanced serotonin levels, for example, can contribute to depression, but also increase pain sensitivity.

When Depression Comes First

Sometimes, depression comes first, and the symptoms, including disruptions to sleeping and eating patterns, contribute to worsening physical health. Some people with depression overeat, which can lead to weight gain and an increased risk of illnesses like diabetes and heart disease. Other depression sufferers have no appetite, and can develop problems related to malnutrition.

Sleep problems can lead to illness in multiple ways. Our immune systems work while we sleep, producing infection fighters, so lack of sleep can make us more vulnerable to bacteria and viruses. Sleep disturbances are also associated with heart disease, high blood pressure and hormone imbalances.

When Physical Illness Comes First

When physical illness comes first, it can lead to depression simply because of the emotional impact of the suffering and losses involved. Ongoing sickness can also lead to increased isolation and a breakdown of support systems. Another way disease can lead to depression is through the mechanism of inflammation. As with the stress response, inflammation is a bodily response which is helpful in combating threats, but can be problematic when it continues too long. A wide range of diseases and conditions have been linked to inflammation, including asthma, arthritis, ulcers, Crohn’s disease, heart disease and some cancers. A fairly recent understanding is that depression may be an inflammatory condition as well. Inflammation and depression have been linked through brain imaging and various other studies, including one that found that people with depression had 31 percent higher levels of CRP (a marker of inflammation) than found in the general population.⁵

Improving Physical and Mental Health

Treating the dual problem of depression and physical illness is best done by addressing as many factors as possible and by making sure that treatment for one condition doesn’t worsen another. Many common prescriptions have depression as a possible side effect, so it’s wise to discuss the possibility with your doctor. Treatment depends on personal circumstances, but focusing on the ways you eat, sleep, breathe, move and relax can set a good foundation for any other needed interventions.

• Diet – Eating a diet focused on optimizing nutrition and minimizing inflammation is wise. Food allergies and sensitivities may contribute to inflammation, so some personal experimentation may be needed.
• Sleep – Experts recommend aiming for about eight hours of sleep a night, and having regular bedtime hours that don’t vary much from day to day.
• Breathing – It’s wise to pay attention to both what you breathe and how you do it. Many environmental toxins contribute to inflammation and other mental and physical challenges, so improving the air in your home, by using low-toxicity personal care and cleaning products, can reduce the load on your body and brain. Learning to breathe more deeply and slowly can also improve health and turn down the stress response.
• Exercise – Regular exercise can improve physical and mental health, in part by lowering inflammation. Even low intensity activities like walking can be very beneficial.
• Stress management – Although it’s not always possible to change stressful circumstances, it’s possible to moderate the body’s response. Meditation, journaling and other relaxation practices can move us out of “fight or flight” mode and into “rest and digest,” where the body and brain can heal. Counseling can help, and even simply taking time during the day to read a joke or two, or look at pictures that bring peace or joy, can have a positive, cumulative effect. Over time, seemingly small changes can produce meaningful improvements in your quality of life.

Sources

¹ “Major Depression.” National Institute of Mental Health, Accessed June 15, 2018.

² “The Health of America.” Blue Cross Blue Shield, May 10, 2018.

³ Sathyanarayana, T. S. et al. “Understanding nutrition, depression and mental illnesses.” Indian Journal of Psychiatry, April-June 2008.

⁴ Tello, Monique. “Diet and depression.” Harvard Health, February 22, 2018.

⁵ Cepeda, M. S. et al. “Depression Is Associated With High Levels of C-Reactive Protein and Low Levels of Fractional Exhaled Nitric Oxide.” The Journal of Clinical Psychiatry, December 2016.