What if depression was just a side effect of inflammation in the body? What if we felt emotionally crappy simply because our body was also down in the dumps?
Some experts are suggesting that depression could just be a reaction to higher levels of inflammation in the body, and that it’s not just a psychological condition.
For example, researchers who published a study in October 2014 in the journal JAMA Psychiatry found that children who had higher levels of inflammation at 9 years old were more likely to have depression when they turned 18 years old.
Researchers used data from a longitudinal study based in Avon County, England. There were about 4,500 participants.
Researchers measured levels of interleukin 6 (IL-6) and C-reactive protein (CRP), since these are considered inflammatory markers in the body.
Those children who had higher levels of IL-6 were more likely to have depression and psychotic experiences, according to the study.
Dr. Angelos Halaris, a psychiatrist at Loyola University Medical Center, agrees that there is a link between depression and inflammation.
“When the person feels stressed, and even if the person denies to themselves that they are stressed, the immune system goes on hyper alert and becomes activated in an effort to protect the individual from the potentially deleterious effects of stress,” Halaris said in an email.
“One of the weapons of the immune system is to instigate an immune response known as inflammation,” he added. “We know now inflammation occurs in the brain and the rest of the body. “
As part of the inflammation process, proteins called cytokines are released and interfere with the healthy functioning of neurotransmitters, especially serotonin, which can lead to a deficiency in the brain.
This deficiency can lead to depression.
“If inflammation persists, certain chemicals in the brain are produced in excessive amounts and can poison, indeed destroy, nerve cells while at the same aggravating depression and leading to suicidality,” Halaris said.
In fact, his research has found that patients diagnosed with major depression had significantly higher levels of IL-6 than the healthy controls, according to a press release.
And since many heart disease patients also suffer from clinical depression, and those who have clinical depression are at risk for developing heart disease, Halaris has recommended a new subspecialty called “psychocardiology” to more effectively diagnose and treat patients.
Christina Major, a holistic nutritionist, herbalist and lifestyle coach, suggests looking at the bigger picture in regards to depression and inflammation, such as what is causing inflammation in the first place.
“Poor food choices are one of the causes of inflammation and depression,” Major said in an email. “Food that is not right for your metabolic needs inflames the gut, causes unbalance in the adrenal glands, and weight gain.”
This includes food that comes in a box or bag (sorry McDonald’s lovers!).
Dr. Elias Aboujaoude, a clinical professor at the Department of Psychiatry and Behavioral Sciences at Stanford School of Medicine, brings up the point that it’s unclear whether depression leads to inflammation first, or if inflammation causes depression first.
“Regardless, this link tells us that the stress that the body of the depressed person senses is high enough to trigger their immune system and an inflammatory response,” said Aboujaoude, also the co-founder and CMO of eTherapi.
Dr. Krystal Richardson, a naturopathic doctor in Washington, siad that depression may in fact be caused by many different triggers, and as a result there could be multiple effective treatment options besides regulating serotonin and dopamine.
Although it’s unclear what causes inflammation in the first place, she believes we are all one step closer to knowing the answer.
“Many of the diseases that affect the body, including cardiovascular disease and cancer, are due to inflammation, so it makes sense that inflammation would play a role in what has once been thought of as a disease of the mind: depression,” Richardson said in an email.
“This highlights the importance of treating the whole person, and that body and mind are often linked together in disease.”
Khandaker, Golam; Pearson, Rebecca; Zammit, Stanley; Lewis, Glyn and Jones, Peter. JAMA Psychiatry. Association of Serum Interleukin 6 and C-Reactive Protein in Childhood With Depression and Psychosis in Young Adult Life: A Population-Based Longitudinal Study. 2014; 71(10): 1121-1128. Doi: 10.1001/jamapsychiatry.2014.1332. January 22, 2015.
Williams, Caroline. TheGuardian.com. Is depression a kind of allergic reaction? Web. January 22, 2015.
Loyola Medicine. Loyola Psychiatrist Proposes New Subspecialty for Patients Suffering Depression and Heart Disease. Web. January 22, 2015.
Halaris, Angelos. Email interview. January 21, 2015.
Major, Christina. Email interview. January 21, 2015.
Aboujaoude, Elias. Email interview. January 21, 2015.
Richardson, Krystal. Email interview. January 21, 2015.
Reviewed January 23, 2015
by Michele Blacksberg RN
Edited by Jody Smith