A survey by Aviva UK Health found that half of UK adults (26 million people) would feel uncomfortable or unsure about telling others if they experienced a mental health problem.
Corin Pilling, deputy director of Livability, told Premier churches have a vital role tackling the issue.
He said: "It's really about trying to create communities where we normalise talking about our well-being.
"There's a real need for us to start normalising the level of conversation that we have in our churches.
"The reality is that there's quite a negative impact when we don't start talking about these things."
The survey also focused on how mental health among young people.
It found that young adults aged between 16 and 24 are the most likely to experience mental health issues, citing money issues and body image concerns as the main causes but they were least likely to be open about it.
The findings also showed that most young people think being called a "snowflake" is damaging to mental health.
The term is used to criticise how hypersensitive, and easily offended and hurt the young generation are sometimes perceived to be.
Pilling encouraged churches to move away from criticism and adopt a culture of complete honesty.
He said: "Developing a culture of honesty isn't easy.
"That's something that needs to come from the top and the bottom.
"Both our leaders themselves need to start talking about their own emotional and mental well-being but also, within younger adult's groups, we need to be looking at material that opens these things up."
Pilling added that the most important thing is reassuring those struggling with mental health issues that people can still recover and live good lives.
"That's the key thing for churches to grasp," he said.
"We have a gift of hope within our faith.
"We believe in the God of hope within our inner-most being and we're not called to carry these things on our own.
"We have each other to do that."
Listen to Corin Pilling speaking With Premier's Rosie Wright and John Pantry here:
