What is the difference between mental health and mental illness?

'Mental health' and 'mental illness' are terms that are often used interchangeably. This seems to happen more frequently as the conversation around mental well-being becomes more open and the stigma around mental illness eases. However, the two do not have the same meaning. While everyone has mental health, not every person has a mental illness.

What is mental health?

The World Health Organization (WHO) defines mental health as: 'A state of well-being in which every individual realises their own potential, and can cope with the normal stresses of life, work productively and make a contribution to their community.'

It also famously says that 'there is no health without mental health', which impacts on our emotional, psychological, and social well-being. It affects how we think, feel, and act. Our mental health is present at every stage in life - from childhood to adulthood. We likely experience different mental health problems as we grow up, such as low mood or stress. These are not always categorised as an illness, though.

Several factors can contribute to mental health problems

These include:

  • Biological factors - such as genes or brain chemistry.
  • Life experiences - such as past trauma or abuse.
  • Family history of mental health problems.

Why are the terms mental health and mental illness often used interchangeably?

Some interchangeable words, such as sweater and jumper, or sneakers and trainers, do have the same meaning - it simply depends on where you're from. However, there are many words and phrases we use interchangeably without thinking that they have different meanings. Examples include sex and gender, tablets (tablets only) and pills (tablets, capsules and caplets) and guarantee and warranty.

When it comes to mental health and mental illness though, the two are very different. The World Health Organization reports that depression affects around 264 million people worldwide. While mental illness is incredibly prevalent in various forms, it isn't something everyone lives with.

Fundamentally, the difference is that mental health can be both positive and negative - you can have good mental health, just as you can have poor mental health. Mental illness is, by definition, a set of symptoms which constitute a problem.

Melanie Pledger, CEO and founder of DNA Light Up, says the interchangeability of the two terms suggests a willingness for people to develop more mental awareness.

"This is a good thing; however, the word 'health' doesn't necessarily mean 'healthy'. Perhaps it would be clearer to focus on 'mental well-being' rather than health," she says.

In what ways are mental health and mental illness similar?

Mental health problems are common, as we all face trials and tribulations and testing circumstances throughout life. Recovery from a mental illness is possible, but so (in some cases) is overcoming your mental health problems before they develop into a diagnosable illness.

Pledger says the similarities between mental health and mental illness are simply in the growing awareness around these issues. Health, illness, sickness and wellness are often all bunched in a variety of conversations. That's why the differentiation between 'health’ and 'illness' has become rather blurred.

How does mental illness differ from mental health?

"Illness confirms a problem, a diagnosis, a recognition, and therefore the requirement to take action," says Pledger.

She says health is a maintenance and requires an awareness of what’s going on, and when to take action. On the other hand, mental illnesses include a range of conditions with symptoms that impact peoples' lives in numerous ways. There are standard criteria used to diagnose illnesses, such as depression and anxiety. An illness has a significant impact on how a person feels, thinks, behaves and interacts with others.

At what stage does a mental health issue become mental illness?

This is a complex question. There are so many mental illnesses and they present themselves differently in everyone. Even two people with the same diagnosed illness will not always have the same symptoms. Pledger echoes this, saying it is very much dependent on the individual. She also says ignoring signs of mental illness and allowing them to escalate without talking to someone can lead to illness. 

"In my personal experience, many of us have been trained in the 'carry on regardless' regime. This has us bottling up our feelings out of fear of appearing weak or being a burden. While mental well-being is much more of an accepted discussion point now in many areas of society, there are still the echoes of shame that, to this day, prevent people from speaking out or taking action. When things are bottled inside a protective shell, the pressure eventually becomes too much. This is when meltdown happens, and illness becomes a stark reality."

How might you practise self-care for mental health versus the more intense forms of treatment for mental illness?

"The first step is awareness," says Pledger on caring for mental health. "Understanding how to check in with others and yourself is really important. We need to deliberately foster the habit of noticing what's going on with our minds."

She stresses the importance of using 'in the moment' techniques to calm mental health problems, such as breathing exercises or medication. There are a number of simple and easy techniques (maybe it's just closing our eyes and counting to 10 when we feel stressed) to address how we're feeling.

"Fostering those kinds of simple practices can go a long way to maintaining and improving mental well-being," Pledger says.

When it comes to mental illness, treatment depends on the type of illness, its severity and what your doctor believes is appropriate. In many cases, a combination of treatments works best - for example, medication and counselling.

The types of medication used to treat mental illness

These include:

  • Antidepressants - these treat depression, anxiety and sometimes other conditions. They can help improve feelings of sadness and despondency, boost energy and motivation and improve concentration.
  • Anti-anxiety medications - these are used to treat anxiety disorders, such as generalised anxiety disorder or panic disorder. They may also help reduce agitation and insomnia
  • Mood-stabilising medications - mood stabilisers are commonly prescribed when treating bipolar disorders, which cause extreme mood swings. This medication might be prescribed alongside antidepressants.
  • Antipsychotic medications - these are drugs typically used to treat psychotic disorders, such as schizophrenia.

Other forms of treatment offered to people with mental illnesses

These include:

  • Psychotherapy.
  • Case management.
  • Support groups.
  • Hospitalisation (in minority cases).
  • Self-help plans.
  • Peer support.

Where can you reach out for support if you are struggling with your mental well-being?

Pledger highlights the importance of reaching out to someone you trust, such as a friend or a family member.

"Often, simply the act of reaching out and allowing yourself to feel seen and heard is the best healing tonic known to mankind. A friend does not need to offer advice. They simply need to listen. When we speak out about what's really going on inside, all of a sudden we're able to tap into solutions for ourselves," she says.

If you are worried about your mental health, or your well-being levels are decreasing, do consult a GP. Don’t wait for your symptoms to worsen before believing there is something wrong or worthy of treatment. A professional will be able to create a suitable treatment plan with you, both for the short and the long term.

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