A CEO from an engineering firm responds: "I don't believe that customers should come first, I believe that employees should come first. It's a tenant at my company. It is a cornerstone of my company to have happy well-adjusted employees."

Well-being programs are also becoming table stakes to attract and retain talent, especially younger generations. One CEO says that "employee well-being programs are becoming more of an expectation rather than a perk."

The importance of employee well-being also impacts the bottom line, the respondents add.

"If my employees are unhappy or they're going through whatever stresses that they are encountering at home in their personal life, they bring that in," another CEO says. "If you have a big team environment that we work in…it can cause absenteeism. People who aren't focused at work, it creates delays with projects so things get backed up at work."

The respondents are also candid about their own struggles with significant work stress, though many say they are successful in "compartmentalizing that anxiety" – and hiding any signs of it from employees because of the "contagious nature" of workplace stress. As a result, nearly all of the CEOs say they feel some form of isolation in the workforce, and they recognize that this is a concern for their own well-being and work.

But that masking may not really be working after all, some concede.

"I'm sure they feel it when I have stressful situations because I put that back on them," one CEO says. "They can tell by your disposition, you create a level of anxiety within the team concept that we have at our place and that affects them adversely because it makes them feel anxious or unsure about what's going on maybe, within the corporate structure."

While a majority of the respondents measure the success of their well-being programs using metrics such as retention of employees, satisfaction in their role and employee engagement, most of the CEOs agree that a comprehensive employee well-being index would be helpful to measure the level of employee engagement within the programs.

"Employee wellness is increasingly critical to business success and at the top of the agenda for many CEOs and even board members," says Paula Allen, Morneau Shepell's vice president of research, analytics and innovation. "But executives still struggle with methods to properly execute and evaluate that support. LifeWorks is positioned to address these concerns."

Read more: 

• Employers shift benefit strategy focus to well-being, broader packages and new tech
• A better place to work: How well-being impacts the bottom line
• For younger professionals, wellness programs are a must