Almost three in 10 employees will suffer from a mental health problem in any one year, according to recent research, with the average length of time off work 30 days for every case.

With more pressure on staff to cope in tougher times, the potential for overloading employees is obvious. But every organisation should be aware of the symptoms of stress so they stand a chance of being able to tackle it before it becomes a fully blown issue.

"Spotting and doing something about troubled employees is an important business skill," said Gill Trevelyan, head of training and equality services at employee relations service ACAS.

"As well as being good managers in the traditional sense, we urge bosses to look out for early indicators before they develop into something more serious, like stress or depression. Healthy and content workers translate directly into productive employees."

Acas offers the following advice on how to spot and deal with mental health problems in the workplace:

Keep your eyes open
The first sign that someone may have depression or a problem with their mental health is often in changes in their day-to-day behaviour. This could be uncharacteristic behaviour such as not being able to cope with their work, seeming distracted or a sudden loss in motivation or absenteeism. Look out for these signs as a potential warning that someone may be suffering from the early stages of depression.

Don't make assumptions
We all have our ups and downs, so a change in behaviour doesn't necessarily mean that there is a problem. If you do notice inconsistent behaviour, try to establish whether it's just a blip, or perhaps the signs of a more serious problem

Get to the root of the problem
It's rare for someone to voluntarily talk about a mental health problem. Approaching a colleague who you feel may be suffering from a mental health issue is not easy. Try and arrange a moment to catch someone privately, and informally ask if they are feeling ok

How can you help?
Depression can sometimes be caused because of a work issue or a personal one. Act accordingly when you establish what the cause of the problem is. If it's work-related then you have the responsibility and control to help remedy it. If it's a domestic issue, then talk to the individual about the changes you can implement to make things easier, such as flexible working. If they have not already found support, point them in the right direction towards help from their GP or a counsellor

Create a culture
Your long-term aim should be to create a working environment which eradicates the stigma mental health can carry. Introducing policies will help doing this, so staff know and feel comfortable in feeling able to talk about the topic. You can also make support options available, like employment assistance programmes or access to occupational health

Walk the talk
A policy will only work if lived out in practice. Work with your HR manager and team to ask them to train management and staff, and teach them to handle things sensitively. Evidence also suggests that exercise, a balanced diet and a healthy work pattern can help treat mild depression, so ask the company to provide advice and encouragement in these areas for the entire workforce