For the sufferer of mental illness, the effects are widespread and dangerous. Disorders spanning eating disorders and psychosis to anxiety and depression are causing significant and long-lasting distress.
The human tragedy is devastating. We know that this is even more the case if people suffer in silence.
Research shows one in three (34 per cent) of people in the UK workforce may have a mental health or wellbeing issue, according to a new PwC study. Meanwhile, nearly a quarter (23 per cent) of 2,000 workers surveyed thought that their organisation did not treat well being sufficiently seriously.
These findings should worry us all. Aside from the human suffering, poor mental health and wellbeing lead to tremendous demand on public services, in turn having a dire impact on the economy and individual performance.
The start is simple: Mental health issues need to come out of the shadows. It is time that changing attitudes in the workplace toward mental health and wellbeing are given long-overdue attention.
Fortunately, this is beginning to happen. From doctors and researchers to trade unions and City firms, decision makers are taking notice and pushing for greater support for mental health.
As Poppy Jaman, programme director for City Mental Health Alliance, a network of City of London-based organisations that are raising awareness of mental health, has previously said: "The business case for addressing mental health and wellbeing has been established and is now featuring on many boardroom agendas."
But with separate data from PwC showing that 40 per cent of employees are not comfortable bringing up a mental health issue with a colleague or boss, and a recent report by YouGov on behalf of the charity Business in the Community finding that 15 per cent of employees face negative consequences if they disclose any mental health issue, more must be done.
The same YouGov report found half of line managers would welcome training on mental health conditions but 35 per cent report not having any workplace support for mental wellbeing. Less than a quarter (24 per cent) of line managers received any training on mental health. This is a good place to start.
Yet given that one in four people is likely to suffer in their lifetime, workplace wellbeing is just one aspect that needs to be taken on board. Normalising mental health disorders is a first step; we must also put an end to the cliff-edge young people face as they leave their support 18th birthday; we must reduce waiting times and make sure everyone who needs to be referred is.
And we must also properly fund services. Health Secretary Jeremy Hunt has promised an extra £1.3bn will be invested annually in mental health services by 2021, and this financial commitment is welcome. Welcome too is the promise of a Green Paper by the end of the year to address mental wellbeing in younger people.
But across my constituency and those of my colleagues, constituents - people - still face inadequate support with large and persistent concerns that money is not reaching the front line and that over half of Clinical Commissioning Groups across England reporting that they plan to reduce the proportion of their budgets they spend on mental health.
As the time has come for businesses to support their staff fully, the time has arrived for the Government to ring-fence mental health spending, which would make a real and sustained difference to local services.
It took too long to get mental health on the agenda. Let us not now spend as long making our workplaces or public services deliver for those who need it.