Depression is one of the most common mental health problems, with around two or three per cent of the population suffering from the illness at any given time.
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Feeling sad and losing your sense of self-esteem, hope or enthusiasm for life are the predominant features of the condition, but cases are as varied as the individuals who suffer from it – and depression can manifest itself in a variety of unexpected ways.
Chronic pain has repeatedly been linked to depression in medical studies, with joint and back pain being among the most frequently observed. A study published this year by the University of Sydney found that people suffering from depression are 60 per cent more likely to experience lower back pain in their lifetime – and that the likelihood increased with the severity of depression.
Other studies have produced similar results, but the correlation between the two problems is not yet fully understood. It is suggested that depression can "magnify" pain sensations and that lack of sleep because of pain can feed depression. Those suffering from depression may also be less likely to engage in physical exercise.
Time seems to drag
They say that time flies when you're having fun, and it seems that the opposite is true for some depression sufferers. A review of studies published in the Journal of Affective Disorders last year found that people with depression consistently reported a slower perception of time passing.
Theories for this vary from a slowing down of the "internal clock" in sufferers to an inability to entnor-epinephrinete" of involvement in an activity – which leads to a feeling of time passing quickly. Mindfulness practices have been found effective in dealing with slow perception of time in depressed people – and many report the therapies help to lift their overall mood.
Constipation occurs when stools remain in the large intestine for too long, becoming hard and dry as too much water is removed from them. What's that got to do with depression you ask? Well it's not always easy to identify an exact cause for constipation – but a correlation has been observed between the two conditions. Up to a third of those suffering from constipation have been observed to also suffer from depression or anxiety.
One theory for this link is that those with depression have decreased levels of the neurotransmitters norepinephrine and serotonin, and we know that 95 per cent of serotonin is produced in the gut. It is thought to play a key role in maintaining communication between gut and brain – so lowered levels of it could perhaps cause tummy troubles.
Many people suffering from depression lose their appetite, and thus lose weight – while others seek solace in comfort eating and put on weight. If that involves junk food, then the negative feelings after a binge can lead to a further impact on self-esteem, deepening the depression.
Loss of appetite can be an early indicator of the onset of depression in some, but the feeling of sadness or worthlessness which characterises the condition can lead to overeating in others. While a change in diet won't cure the condition, doctors believe a healthy and balanced diet can help manage it.
It's much easier to talk about mental health issues than it was a decade or more ago, but there is still a lingering stigma around them – particularly for some older people.
Expressing anger is still more socially acceptable than expressing sadness, and many depression sufferers also find themselves easily angered or irritated. Intense and unresolved anger may also have a causal link to depression. Mindfulness techniques and anger-management strategies are often recommended to those who wish to bring their temper under control.
Losing interest in hobbies
Losing interest or experiencing less pleasure in one's hobbies and interests is a well-established indicator for depression – whether it be handicrafts, physical exercise or listening to music. An inability to take pleasure from previously enjoyed activities as basic as a nice meal or sex is known as anhedonia. It is now recognised as a core symptom of depression and features in diagnostic questioning – but is not as widely known by the public.
If you feel you may be suffering from depression, make an appointment to see your GP.