What are the lifestyle issues that kill Americans? You might guess smoking, obesity, or the raging opioid epidemic, and you'd be right. But you'd also be missing a quieter but also seriously deadly health menace, according to former surgeon general Vivek H. Murthy -- loneliness.

Forty percent of American adults report feeling lonely (and many more may simply too proud to admit they're suffering), Murthy reports in a recent Harvard Business Review article. That lack of social connection isn't just a personal sadness; it's a raging health crisis. In fact, science shows that loneliness can take as many years off your life as smoking 15 cigarettes a day.

So what's driving our national crisis of disconnection? Of course this is a complicated issue and many factors play a role, but in his article and follow-up interviews, Murthy pulls no punches. Modern work culture is playing a significant part in this deadly epidemic.

Working together but alone

Think of your own office. How often do colleagues look up from their screen for actual face-to-face interaction? If the answer is not at all often, you're not alone, according to Murthy:

In the workplace, new models of working -- such as telecommuting and some on-demand "gig economy" contracting arrangements -- have created flexibility but often reduce the opportunities for in-person interaction and relationships. And even working at an office doesn't guarantee meaningful connections: People sit in an office full of coworkers, even in open-plan workspaces, but everyone is staring at a computer or attending task-oriented meetings where opportunities to connect on a human level are scarce.

Murthy goes on to explain how this lack of connection leads to chronic high stress, inflammation, and a variety of alarming health problems. He also points out that way before loneliness kills you, it starts killing your productivity.

"Researchers for Gallup found that having strong social connections at work makes employees more likely to be engaged with their jobs and produce higher-quality work, and less likely to fall sick or be injured," he reports.

What businesses can do to help

So are we stuck with soldiering through loneliness like we soldier through a nasty case of the flu? Nope, insists Murthy. There are relatively simple steps businesses can take to help employees forge meaningful human connections that will make them healthier, happier, and, as a nice side benefit, also better workers.

When he was surgeon general, for instance, Murthy instituted an exercise called "Inside Scoop" for his team. "Team members were asked to share something about themselves through pictures for five minutes during weekly staff meetings. Presenting was an opportunity for each of us to share more of who we were; listening was an opportunity to recognize our colleagues in the way they wished to be seen," he explains.

All of a sudden people stopped dreading staff meetings and started looking forward to them, he relates, and formerly shy team members became more vocal with their ideas.

Is this particular weekly ritual the solution for every office? Of course not, says Murthy, but his simple (free) intervention is a testament to the fact that businesses can (and should) take simple steps to do their part in countering America's destructive loneliness epidemic.

For more guidance and ideas on how to strengthen ties at your office, check out the complete article.

Do you feel a real connection with any of your co-workers? If not, what could you do to change that?