I realise some of these are serious conditions, so please don’t be alarmed. But it is all too easy to assume that depression is solely due to psychological factors when in reality, some people could benefit from a thorough medical check up - in turn this might identify some physiological matters that could be treated and righted.
With regards to depression in the elderly, there is some research looking into the possibility of cerebro-vascular disease and whether this may "predispose, precipitate or perpetuate some geriatric depressive syndromes"4. For the future, I think it is reasonable to assume there may still be occasions when as-yet-not-understood physiological causes may be shown to be having some impact on some people who are feeling severely depressed.
It is also worth bearing in mind that low cortisol (hypocortisolism) is quite often associated with a physiological reaction to enduring trauma 2; understandably, it is not unusual for people who have been traumatised to feel depressed. Though stress and distress initially raise cortisol levels, over time there can be a compensatory response (sometimes referred to as the negative feedback regulation of the stress response 3) that leads over time to low cortisol. I am not suggesting that these physiological responses need correcting with medications – but it is worth, for a moment, bearing in mind the complex interaction between how we think and feel with physiological changes that occur too. I find that people often find it helpful to have the very physical experiences (as well as the emotional and mental) associated with feeling depressed to be acknowledged. With regards to depression, it’s equally misleading to say “it’s all in the mind” as it is to blame brain chemicals.
Conversely, prolonged high levels of cortisol in response to stress and distress - one aspect of the oft-called “flight-fight response” (providing a boost of hormones to help us deal with a threat or flee to safety) - can be a contributory factor in a person feeling depressed. This seems feasible in that Cushing’s syndrome (an endocrine disorder that results in high levels of cortisol) is commonly associated with people feeling extremely depressed. In effect, this means that continued stress and/or distress can make us feel depressed. Understanding this mechanism can be helpful and somehow helps ground the experience. It sort of makes sense, just as a person expects to sweat when running or to feel tired after a large meal: these are natural responses.
The examples we have looked at here are very different from the widespread myth that asserts that depression is a medical condition caused by low serotonin in the brain [more on that in this web site here]. All emotions, actions, and reactions are responses to chemical changes in the body and in turn lead to further chemical responses. This does not mean that feeling depressed is symptomatic of a chemical imbalance that should then be corrected by medications; after all, drugs are not going to change a person’s circumstances, including social oppression and injustice that can precipitate feeling depressed, or change the way we think about ourselves. Clearly a hormone problem such as hypothyroidism is quite different and can easily be treated. Practically, some of the physiological effects of stress and distress can often be reversed by physical exercise and also activities that help us relax (that I mention here) which could have the opposite effect of the flight-fight response on our central nervous system.
Diet and depression
I think the link between depression and diet is underrated. We forget that the fuel from which our brains and the rest of our bodies are formed and replemished is the food we eat. We are perhaps far too quick to try to separate off the mental/emotional from the physiological when in reality this is a false dichotomy.
Many people may be deficient in vital micronutrients (vitamins and minerals) as modern farming methods, long food storage times (in transport from overseas or on supermarket shelves), and a preference for fast foods have reduced some of the nutritional content of our food. Some low levels and deficiencies sometimes associated with feeling depressed might include: vitamin D, vitamin B12, B6, B9, selenium, iron, tryptophan, zinc, omega-3 (for further details on some of these, see here for example). This study concludes that there is evidence (though limited) to support the use of omega-3 fatty acids (found in fish oils and also flax seeds, for example) for some people who feel depressed.
As I mentioned here, high sugar diets can lead to severe mood dips too; furthermore, high levels of sugar deplete levels of essential micronutrients in the body too.
Medicines can cause depression
Depression can be a side-effect of prescribed medications 1, for example: amphetamines (including drugs such as Ritalin used with children diagnosed with so-called ADHD [I write about these drugs here]; benzodiazepines (such as valium); corticosteroids (anti-inflammatory medicine in creams, tablets, inhalers [more here]; statins; some antibiotics; triptans used to treat migraine 5; the anti-malarial drug mefloquine (Lariam); anticonvulsant drugs used to control seizures and lithium (also used for so-called Bipolar Disorder); and antipsychotic drugs used to control psychosis. The surprise one is antidepressants – yes, antidepressants can cause depression [I mention this here]. In addition we could add non-prescription drugs such as alcohol, amphetamines and marijuana. This article in the Psychiatric Times draws attention to some of the drugs I have mentioned and to some others too.
It's time to take a look at what might help those who are feeling depressed - here.
References - Bibliography - Further reading
1 Breggin, P. (2001) The Antidepressant Fact Book. US: Da Capo Press
2 Fries, E. et al (2005) A new view on hypocortisolism. Psychoneuroendocrinology 2005 xx, 1-7 Available here.
3 See for example: Van Houdenhove, B. et al (2009) Does hypothalamic–pituitary–adrenal axis hypofunction in chronic fatigue
syndrome reflect a ‘crash’ in the stress system? Medical Hypotheses. Available here.
4 Taylor, W.D. et al (2013)
The vascular depression hypothesis: mechanisms linking vascular disease with depression. Molecular Psychiatry
5 Ostermann, K. et al (2012) Possible association of severe major depression with acute cessation of long-term excessive triptan use. J Clin Pharm Ther. 2012 Sep 27. doi: 10.1111/jcpt.12009 Abstract here.