What is mental illness?

Unfortunately, mental illness still frightens people. It is often wrongly associated with weakness, loss of control and tragic, high-profile events that often get heavy media coverage. However, many people still hide mental illness. It is not uncommon for people to be completely unaware that someone close to them is suffering from phobias, for example. Because of all the stigma surrounding mental illness, only one out of three people suffering from mental illness will consult a health professional. And yet, these people can be treated and often cured. By mental illness, we mean all the problems that affect the mind. They are manifestations of psychological and often biological dysfunction. These disturbances cause various feelings of discomfort, emotional upheaval and/or intellectual disability, as well as behavioural difficulties.  
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What causes mental illness?

In spite of the research available in this field, we still don’t know the cause of every mental illness. However, we do know that there are triggers and painful events can cause the onset of an illness—for example the loss of a loved one, a divorce, losing one’s job, an accident or a serious illness.

Furthermore, we now know that there is a biological origin to certain illnesses. Thanks to modern technology, we are increasingly able to understand the way the brain functions. Certain substances identified by researchers, such as serotonin (a neurotransmitter), play an important role in the development of mental illnesses like depression.

Research indicates that mental illnesses result from a complex interaction of genetic, biological, and personality traits as well as social environment. This is known as the “bio-psycho-social” model, an approach that posits that biological, psychological and social factors all play a significant role in the context of illness, in contrast to the traditional model that reduces illness to a single factor.

That being said, the brain is still the one “in charge” of behaviour, thought, mood and anxiety. However, the links between specific cerebral dysfunctions and specific mental illnesses are not entirely known (Kessler, R.C. and Ahangang, Z. (1999), paraphrased in Health Canada et al. (2002). A Report on Mental Illness in Canada, Ottawa, p. 22) which prompted Health Canada to point out: “It is important not to over-interpret the available evidence about the role of either genetic or environmental factors in causing mental illnesses as much more research is needed to fully understand the causes of mental illness.” (Health Canada et al. (2002), A Report on Mental Illnesses in Canada, p. 22.)

Corroborating this line of thought, researchers from the Régie régionale de Montréal-Centre add: “The chains of causality of mental disorders are complex. In spite of this limit to our knowledge, it is possible to reduce the incidence of mental disorders by acting, before they appear, on the biological, psychosocial or physical factors known for their causal role. Prevention attacks both risk factors and pathogenic conditions.” (Régie régionale de la santé et des services sociaux de Montréal-Centre. (2001) Rapport annuel 2001 sur la santé de la population : Garder notre monde en santé, un nouvel éclairage sur la santé des adultes montréalais, p. 64.)

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Risk factors

As previously noted, we don’t know the exact causes of mental illness. However, studies suggest that mental illness can be the result of a combination of factors.

Certain events, such as a break-up, the death of a loved one, financial problems, poor physical health and disabilities are all risk factors for which preventive action is possible.

Other factors such as a family history of mental illness, physical, sexual and psychological abuse during childhood, prior episodes of mental illness, psychological trauma or accumulated stress can also cause the development of mental health disorders.

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Popular beliefs and taboos

A study on public perceptions of mental illness performed in 1997 by the Royal College of Psychiatrists, concluded that people who have suffered from mental illness were perceived as dangerous and unpredictable, difficult to talk to, responsible for their problem, unlikely to get better and not likely to respond to treatment. (Hayward, P. and Bright, J.A. (1997) “Stigma and mental illness: a review and critique.” Journal of Mental Health, vol. 6, p. 345 to 3543 cited in Conseil médical du Québec. (2001) Mental Disorders: a Modern Picture)

According to another study conducted in 2001, three popular beliefs created a barrier to diagnosis and treatment: (Roper Starch Worldwide Inc. (2001) cited in Conseil médical du Québec. (2001) Mental Disorders: a Modern Picture)

Beliefs about a diagnosis

  • Symptoms are not associated with a mental disorder: 93% of people who have not been diagnosed do not associate their symptoms with a mental disorder, even if almost half admit that their symptoms cause them distress and limit their social functioning.
  • The symptoms can be self-treated: almost half of people who have been diagnosed will not see a health care professional because they think they can overcome their illness on their own.
  • The diagnosis itself is stigmatizing: almost half of people who have received a diagnosis are embarrassed by their illness, while only 17% of those who have not received an official diagnosis, but who have symptoms of mental illness, have this feeling. Twice as many people who have received a diagnosis of mental illness are afraid to talk to their friends about their illness.

Beliefs about treatment

  • Non-specific treatments, such as increasing physical or social activity, relaxation, stress management, reading about people who have gone through the same things, are highly valued, while psychiatric treatment such as medication or hospitalization are considered harmful. From this point of view, vitamins and special diets win out over antidepressants and antipsychotic drugs.(National Mental Health Association Survey cited in Conseil médical du Québec. (2001) Mental Disorders: a Modern Picture)
  • Some researchers have tried to understand the impact of the sociocultural context, in particular the influence of public opinion on the choice of treatment, the acceptance of different psychiatric treatments and the individual’s willingness to follow the treatment. The results suggest that psychotherapy is held in high esteem by the public, while psychopharmacology is rejected by the large majority of respondents.(Angermayer and Matschinger (1996) cited in Conseil médical du Québec. (2001) Mental Disorders: a Modern Picture)
  • And yet, a recent study confirms that the combination of medication and therapy leads to a success rate of 85% among people who suffer from mental illness.(Keller, Martin. (2001) “January Report.” in Journal of the American Medical Association (JAMA)

In short, it is important to remember that popular beliefs about the causes and treatments of mental illness differ a great deal from those of health care professionals, particularly psychiatrists. These beliefs limit the optimal use of health care services. (Conseil médical du Québec. (2001) Mental Disorders: a Modern Picture)


Taboos and stigma about mental illness have an impact on the Canadian economy. In their analysis of the economic cost of mental illness, Thomas Stephens and Natacha Joubert concluded their report by saying, “Even with these improvements in data [to determine the direct and indirect costs of mental illness], the economic burden of mental health problems will likely continue to be underestimated until they are reported as openly as are basic physical health problems.” (Stephen, T. and Joubert N. (2001) “The Economic Burden of Mental Health Problems in Canada,” in Chronic Diseases in Canada, Population and Public Health Branch of Health Canada, p. 11.) 1

1. Stephens and Joubert (Stephens, T and Joubert, N. (2001), p. 1.) maintain that:

  • Mental disorders ranked seventh among the 20 disease categories for which cost estimates were published.
  • Direct costs for treating medically diagnosed mental disorders totalled $6.3 billion (1998), which included $3.9 billion for hospital care, $887 million for other institutional care, $854 million for physician care, and $642 million for prescription medications.
  • Additional indirect costs totalling $3.0 billion included short-term sick days ($866 million), short-term disability ($1,707 million), and premature death ($400 million), although these latter amounts were not restricted to diagnosed disorders.