The charity has compiled research which shows that six out of 10 Britons find it difficult to cope mentally.
The YouGov poll is released together and is aimed to promote the agency's annual Mental Wellbeing Week, which takes place this week.
The research found that stress, anxiety and depression are the three most common difficulties encountered by the total sample.
Some 32 per cent stated that they have actually been worried that they were ‘cracking up' at one point or another.
Together CEO Liz Felton said: ‘This research shows that mental health and wellbeing is an issue relevant to most people, not just those with diagnosed issues. We hope the results go some way to try and reduce the ‘them and us' mentality about the topic that can lead to stigma, and perhaps prevents some people from seeking help, or talking about what they're going through when they need to.'
The story was embargoed until this morning and has been covered in the Metro and a segment on GMTV.