Inflammation and Depression

Is There Cause For Concern?

Contributed by

Dr. Fay
Kazzi Shanholtzer

In this day and age, the world appears to be well versed on the varying topics of mental health.  However, there still seems to be a disconnect when it comes to some of the leading mental health disorders, such as depression.  Very much like the body, the mind can literally get sick.  The mind manifests its illnesses through a myriad of ways, such as ongoing migraines, confusion, forgetfulness, brain fog, and slow or poor processing of information.  One of the most complex and underestimated facets of mental health challenges is the deep, dark, and isolating state of chronic depression.  In many cases depression goes unaddressed mostly due to its apparent non-urgency.

Let me try to put this in perspective.  When a person shows up with a deep gash to the leg, blood everywhere, and writhing in pain we instantly recognize the severity of the situation and that this person is in desperate need of help.  We can see the violent circumstance they’re in and thus respond and sympathize accordingly.  If a person walks in a room who appears to be young with a bald head, pale complexion, hunched over, and emaciated, it won’t take too much for us to recognize their state, have our hearts go out to them, while trying not to make it so obvious that we know they have some form of terminal cancer.  Our sympathies are there because we can “see” the sickness.

Mental health issues are so much more difficult to understand and treat because the manifestations, whether demotivation, sadness, fatigue, or despair, appear to be superficial in nature and easily manageable if one would simply “snap out of it,” “control their thoughts,” or “just get over it.”  Or so we think.  But this is a serious problem into today’s world.  In fact over 150 million people worldwide are affected by depression and as a result it is the leading cause of losing healthy years of one’s life as a result of disability (1).

*As a disclaimer, this article is not designed to minimize or undermine all forms of depression.  There are life-altering circumstances and tragedies that can cause tremendous grief for prolonged periods of time that can lead someone to experience the full force of depression episodes, and these are of themselves not the type of depression we are referring to.  Grief is a very human expression of the sad and hurtful things that happen in one’s life.  Categorization is challenging to do in this scenario since mental health is a heavily layered subject, but this article is intended for the purpose of exploring the form of depression in the context of non-life altering scenarios.  More like the unpleasant gloominess that constantly appears to hover over someone without a definitive reason of tragedy associated with it.

Can depression be related to having an inflammatory condition?

Inflammation can best be described as “a localized physical condition in which part of the body becomes reddened, swollen, hot, and often painful, especially as a reaction to injury or infection.”  You might be thinking, “are you suggesting that some people who appear depressed are actually experiencing a sort of an inflammatory condition in their bodies that manifests itself with a mental state of depression?” 

This seems to be what research has been showing us.  A review of the available evidence has shown that major depressive disorder or depression, in the absence of medical illness, is associated with raised inflammatory markers (2).  The evidence has also gone so far as to suggest that you could literally induce depression by inducing inflammation.  We can see the direct impact of this with cancer patients who, after receiving interferons, 50% go on to experience major depression (3). 

But then you might say “Well, couldn’t it be that they are depressed because they have cancer?”  And that’s a good point, which is why this is especially interesting.  It was also found that even the administration of vaccines caused enough inflammation to trigger depressive symptoms (3).  In other words, inducing pro-inflammatory states increases the incidence of mood symptoms in these studies.  This is remarkable insight as it emphasizes the validity of the mind-body interaction in a very intimate manner, and also highlights potential ways to improve the existing treatment methodologies of mental illnesses.

If inflammation can cause depression, then can anti-inflammatory practices reduce depression?

We’ve all heard about anti-inflammatory foods, supplements, breathing techniques, and exercises.  This is getting a lot of attention now since we are finding that inflammation is the common denominator to the major killers in our world today.  According to the Harvard Medical School, “mounting evidence suggests a common underlying cause of major degenerative diseases.  The four horsemen of the medical apocalypse — coronary artery disease, diabetes, cancer, and Alzheimer’s — may be riding the same steed: inflammation,” (4).  Knowing this, if we can induce a state of inflammation that can lead to depression even without any underlying health issues, then can we in the same way reverse inflammation with anti-inflammatory practices?  Research is unapologetically showing us that YES this is possible.  And we all need to take advantage of it, not just for our body’s sake, but also for our minds!

Researchers followed the diets of 43,000 women for 12 years who were not clinically diagnosed with depression beforehand and found that those who ate a more inflammatory diet (ie: junk food such as sodas, refined grains, meat, dairy) became depressed.  As a scientist, I love research like this because it follows large amounts of people over a huge gap of time and can reveal very strong evidence in favor of the hypothesis in question.  The study went on to report “This finding suggests that chronic inflammation may underlie the association between diet and depression” (5).  Wow!  Couldn’t have put it in a clearer statement.

So, you’re thinking “You mean to say that I get more depressed when I eat food that should make me happier?  But don’t they call it comfort food because it boosts your mood?”  Yes, it makes you happy in the moment that you’re eating it since you’re mostly enjoying the flavor and textures.  But that happy feeling is fleeting, it’s followed by a crash, and what you’re left with is your body-protection mode kicking in.  And it does this by triggering inflammation.

What is the most anti-inflammatory diet I can follow?

As we’ve seen above, if you’re interested in combating depression in the safest way possible, and that does not involve the use of prescription drugs or other conventional forms of treatment, then considering your diet as a therapeutic approach is both scientifically and practically recommended.  The most anti-inflammatory diet is a plant-based one which can cut c-reactive proteins (the inflammatory markers) by 30% within just two weeks of application.  This is due to the anti-inflammatory properties in plants known as antioxidants (6).

So, you might be thinking why are antioxidants anti-inflammatory? This is an important question as it will support the backbone of what will form your commitment to a plant-based lifestyle.  Oxidative damage caused by free radicals can cause an autoimmune response by changing the chemical structures of otherwise ubiquitous molecules to generate a variety of new structures that the body attacks as foreign (7).  An example of this is when LDL (“bad” cholesterol) gets oxidized, the body creates antibodies against it to attack it, and this leads to inflammation, the buildup of plaque, and you know the rest.  Foods such as fruits, vegetables, nuts, whole grains, fiber, legumes are loaded with these fighter antioxidants that can neutralize the effect of the free-radicals, and thereby protect you from what would have caused a surge of inflammation.  Plant-based foods are immunity superheroes!

Eat healthy, be happy!

If you’re wondering that surely diet can’t have that much of an influence on the quality of life and pleasure one experiences, then I’ll give you one more impressive piece of research.  Have you heard of the term Anhedonia — the inability to feel pleasure?  It’s one of the major symptoms of depression.  You no longer feel like doing the things that used to bring you much joy and satisfaction.  It’s the icky part of depression that makes people so demotivated with life that they can’t even bring themselves to get out of bed.  And for others it can even drive them to commit suicide.  When subjects are exposed to endotoxins, which are harmful components found mostly in animal meats and other processed foods, within just hours of consumption depressed mood and anhedonia significantly increased (8).  The endotoxins we get from an unhealthy diet can literally cause us to lose joy in our life. So scientifically speaking, we CAN decrease and even treat depression with the removal of these unhealthy foods while increasing the consumption of antioxidant rich foods.

You may have heard it said that “happiness is a choice.”  But really, what the science is showing us, is that we get to choose what we eat and drink and ultimately it is that choice that can have an influence on our mood and overall wellbeing.


  1. Madeeh Hashmi A, Awais Aftab M, Mazhar N, Umair M, Butt Z. The fiery landscape of depression: A review of the inflammatory hypothesis. Pak J Med Sci. 2013;29(3):877-884. doi:10.12669/pjms.293.3357
  2. Hashmi AM, Butt Z, Umair M. Is depression an inflammatory condition? A review of available evidence. J Pak Med Assoc. 2013;63(7):899-906.
  3. Rosenblat JD, Cha DS, Mansur RB, McIntyre RS. Inflamed moods: a review of the interactions between inflammation and mood disorders. Prog Neuropsychopharmacol Biol Psychiatry. 2014;53:23-34. doi:10.1016/j.pnpbp.2014.01.013
  5. Lucas M, Chocano-Bedoya P, Schulze MB, et al. Inflammatory dietary pattern and risk of depression among women [published correction appears in Brain Behav Immun. 2015 May;46:327. Shulze, Mathias B [corrected to Schulze, Matthias B]]. Brain Behav Immun. 2014;36:46-53. doi:10.1016/j.bbi.2013.09.014
  6. Jenkins DJ, Kendall CW, Marchie A, et al. Effects of a dietary portfolio of cholesterol-lowering foods vs lovastatin on serum lipids and C-reactive protein. JAMA. 2003;290(4):502-510. doi:10.1001/jama.290.4.502
  7. Maes M, Galecki P, Chang YS, Berk M. A review on the oxidative and nitrosative stress (O&NS) pathways in major depression and their possible contribution to the (neuro)degenerative processes in that illness. Prog Neuropsychopharmacol Biol Psychiatry. 2011;35(3):676-692. doi:10.1016/j.pnpbp.2010.05.004
  8. Eisenberger NI, Berkman ET, Inagaki TK, Rameson LT, Mashal NM, Irwin MR. Inflammation-induced anhedonia: endotoxin reduces ventral striatum responses to reward. Biol Psychiatry. 2010;68(8):748-754. doi:10.1016/j.biopsych.2010.06.010