Depression and Inflammation: Is hidden inflammation affecting your mood?
In the last 2 years we have all experienced Crisis in the form of a pandemic. In New Zealand we have seen a significant increase in Depression and Anxiety during this time(1). With women 58% more likely to be affected by depression than men (2). Termed by psychologists as ‘crisis fatigue’, a combination of chronic stress, anxiety, poor behavioral habits and loneliness, this constant state of pandemic alertness has led to to a state of apathy and burnout for many people (1). How is this connected to inflammation?
Think back to the last time you injured yourself. Perhaps you fell over and hurt your knee, or sprained your ankle playing sport. Along with the pain, you can probably recall how swollen, red and hot the area became. These changes were a sign of your body’s protective inflammatory response springing into action.
Although uncomfortable, inflammation enabled you to heal by forcing you to rest the affected limb and avoid injuring yourself further; protecting the area from infection; and clearing away damaged tissue. As healing occurred, the swelling and redness resolved, and your ankle went back to normal.
If a sprained ankle is what you think of when you hear the word ‘inflammation’, you are probably wondering what a simple injury and depression could possibly have in common. The answer is, more than you think.
Burn, Baby, Burn
There is a type of inflammation you can’t see as it may not be localised to a particular area, or have an obvious trigger, such as an injury. Instead, it’s systemic (affecting multiple areas throughout the body), and occurs on a microscopic scale.
However, just like the inflammation of a sprained ankle, systemic inflammation begins as a protective response to a trigger, such as infection or cell damage, and is designed to help you heal. Unfortunately, if the trigger is persistent, as in the case of chronic disease or infection, environmental exposure to irritants (e.g. pollution, smoking), or even chronic stress, then the inflammation remains constant. This creates a chronic, low-grade inflammatory state, which may damage healthy tissue and disrupt the functioning of many body systems and organs – including your brain.
Tired, Sick, and Depressed
To understand how chronic inflammation can affect mood, let’s consider something called ‘sickness behaviour’. Think back to a time when you had a significant infection – perhaps it was influenza, or a bad bout of bronchitis. How did you feel?
If you’re like most people, you were exhausted; struggled to think; lost your appetite, your sense of pleasure, and your desire to spend time with others; and you probably felt very down. Rather than purely being caused by illness, these feelings were also a consequence of inflammation and, again, were designed to help you heal. How? By creating ‘sickness behaviours’, such as resting and keeping away from other people, which give you the best chance to recover without spreading the infection to others.
In New Zealand between 2020 and 2021 17% of the population was affected by depression which is 703,000 Adults (2). If you are one of these people you may have noticed the similarities between the feelings described above – such as a low mood, anhedonia (loss of pleasure) and fatigue – and how you feel when you’re depressed.
So, if inflammation can create depression-like feelings and behaviours in the context of being sick, can it cause depression in an otherwise healthy person?
Brain on Fire
Although inflammation and depression are definitely linked, researchers are still trying to establish which comes first, inflammation or depression. Here is what we know so far:
Otherwise healthy people with depression have higher levels of markers of inflammation in their blood compared with non-depressed, healthy individuals, including the systemic inflammatory marker, C-reactive protein (CRP)(3).
Children with elevated levels of CRP in their blood are more likely to develop depression 5 to 10 years later as young adults (4).
People who have been depressed for a long time show 30% more brain inflammation than those who are depressed for a shorter amount of time (5).
Depression is significantly more likely to develop in people with other inflammatory disorders, such as rheumatoid arthritis, chronic pain, obesity, diabetes, and cardiovascular disease (6).
Anti-inflammatory medications have been shown to reduce the severity of symptoms of depression (7).
Reducing inflammation
The good news is that reducing your level of inflammation (also called your ‘inflammatory load’) could help with your mood. You can influence your inflammatory load by tweaking your daily diet, exercise and supplements.
Anti-inflammatory foods
Your diet can either promote or reduce inflammation. In fact, people who end up developing depression often have higher intakes of pro-inflammatory foods such as sugar, unhealthy fats, and carbohydrates (8). Swap these foods for anti-inflammatory choices, such as fruits, vegetables, legumes, nuts, seeds, wholegrains and fatty fish. It can be as easy as starting with a bowl of lightly steamed vegetables, a tin of salmon, and some brown rice for lunch.
Exercise
During lockdowns many of us stopped exercising due to many barriers. Now’s the time to start creating that weekly habit again. Just 20 minutes of moderate exercise, such as brisk walking, dancing, gardening or gentle cycling, has been shown to significantly reduce inflammation (9). Additionally, exercise provides well-known mood-boosting benefits, such as an increase in endorphins (feel-good brain chemicals). Start with whatever you can commit to doing at least three times a week, and build from there.
Supplements
Turmeric is one of the most well-researched anti-inflammatory supplements. It significantly improves symptoms of depression when taken for at least four to six weeks, and also reduces anxiety in depressed people, without causing any unwanted side effects(10). In fact, a specific turmeric extract, known as BCM-95™, combined with saffron has shown similar benefits to an antidepressant medication (11). Its also safe to use alongside most SSRIs. Turmeric and saffron reduce neuroinflammation, calm that sympathetic/ stress drive and support HPA axis dysfunction, while also supporting mitochondrial function for energy and increasing BDNF production for enhanced neurogenesis (12,13,14). Turmeric lattes are a great start and using turmeric in your cooking. However to treat depression the dosage of Turmeric is much higher. A naturopath can help with the right dosage for you.
Sensory Rest
We have been told to tune into every piece of news and also needed to for good reason at the beginning of this pandemic. Now with the impacts of the silent pandemic (mental health crisis) becoming the larger crisis for many people its time to actively take more time away from our screens and phones. Treat your news intake and phone use like the gym. Have a set time you go and where you go. Don’t spend more than 30minutes and plan in rest days where you don’t use or engage in news at all. Mental rest is as important physical rest. Just as you don’t go to the gym everyday to allow your body to recover we also need to refrain from reading crisis information to rest our brain.
Put Out the Fire for a Better Mood
Inflammation and depression are inextricably linked. Regardless of which comes first, reducing your inflammatory load is vital in the fight against depression, enabling you to put out the fire of inflammation and achieve a healthy mood. Reducing inflammation in combination with other support such as counselling, and support from a Gp gives people resources to recover and live supported with depression. For help changing your diet and exercise habits, or to help you choose the herbs/supplements that will be the best fit for you, get in touch.
References
1 Gasteiger, N., Vedhara, K., Massey, A., Jia, R., Ayling, K., Chalder, T., Coupland, C., & Broadbent, E. (2021). Depression, anxiety and stress during the COVID-19 pandemic: results from a New Zealand cohort study on mental well-being. BMJ open, 11(5), e045325. https://doi.org/10.1136/bmjopen-2020-045325.
2 Ministry of Health: Annual Update of Key Results 2020/21: New Zealand Health Survey. [Accessed 8 May 2022] Available from: https://www.health.govt.nz/publication/annual-update-key-results-2020-21-new-zealand-health-survey.
3 Slavich GM, Irwin MR. From stress to inflammation and major depressive disorder: a social signal transduction theory of depression. Psychol Bull. 2014 May;140(3):774. doi: https://dx.doi.org/10.2105%2FAJPH.2014.302110.
4 Khandaker GM, Pearson RM, Zammit S, Lewis G, Jones PB. Association of serum interleukin 6 and C-reactive protein in childhood with depression and psychosis in young adult life: a population-based longitudinal study. JAMA Psychiatry. 2014 Oct 1;71(10):1121-8. doi: 10.1001/jamapsychiatry.2014.1332.
5 Setiawan E, Attwells S, Wilson AA, Mizrahi R, Rusjan PM, Miler L, et al. Association of translocator protein total distribution volume with duration of untreated major depressive disorder: a cross-sectional study. Lancet Psychiatry. 2018 Apr 1;5(4):339-47. doi: https://doi.org/10.1016/S2215-0366(18)30048-8.
6 Slavich GM, Irwin MR. From stress to inflammation and major depressive disorder: a social signal transduction theory of depression. Psychol Bull. 2014 May;140(3):774. doi: https://dx.doi.org/10.2105%2FAJPH.2014.302110.
7 Slavich GM, Irwin MR. From stress to inflammation and major depressive disorder: a social signal transduction theory of depression. Psychol Bull. 2014 May;140(3):774. doi: https://dx.doi.org/10.2105%2FAJPH.2014.302110.
8 Firth J, Veronese N, Cotter J, Shivappa N, Hebert J, Ee C, Smith L, Stubbs B, Jackson S, Sarris J. What is the role of dietary inflammation in severe mental illness? A review of observational and experimental findings. Front Psychiatry. 2019;10:350. doi: https://dx.doi.org/10.3389%2Ffpsyt.2019.00350.
9 Dimitrov S, Hulteng E, Hong S. Inflammation and exercise: Inhibition of monocytic intracellular TNF production by acute exercise via β2-adrenergic activation. Brain Behav Immun. 2017 Mar 1;61:60-8. doi: https://doi.org/10.1016/j.bbi.2016.12.017
10 Ng QX, Koh SS, Chan HW, Ho CY. Clinical use of curcumin in depression: A meta-analysis. Journal of the American Medical Directors Association. 2017 Jun 1;18(6):503-8. doi: https://doi.org/10.1016/j.jamda.2016.12.071.
11 Sanmukhani J, Satodia V, Trivedi J, Patel T, Tiwari D, Panchal B, Goel A, Tripathi CB. Efficacy and safety of curcumin in major depressive disorder: a randomized controlled trial. Phytother Res. 2014 Apr;28(4):579-85.
12 Fanaei H, Khayat S, Kasaeian A, Javadimehr M. Effect of curcumin on serum brain-derived neurotrophic factor levels in women with premenstrual syndrome: A randomized, double-blind, placebo-controlled trial. Neuropeptides. 2016 Apr;56:25-31. doi: 10.1016/j.npep.2015.11.003.
13 Xu Y, Ku B, Tie L, Yao H, Jiang W, Ma X. Curcumin reverses the effects of chronic stress on behavior, the HPA axis, BDNF expression and phosphorylation of CREB. Brain Res. 2006 Nov 29;1122(1):56-64. 2006 Oct 3. PMID:17022948.
14 Trujillo J, Granados-Castro LF, Zazueta C, Andérica-Romero AC, Chirino YI, Pedraza-Chaverrí J. Mitochondria as a target in the therapeutic properties of curcumin. Arch Pharm (Weinheim). 2014 Dec;347(12):873-84. doi:10.1002/ardp.201400266.