Among certain modern management gurus, the idea that working from home is good for you is accepted as gospel truth. Telecommuting is “the most in-demand type of work flexibility job seekers are interested in,” one job analyst told TheStreet. “Working From Home Is Good For You And Your Boss,” according to one HuffPost headline. “Telecommuting is the future of work,” declared management guru Meghan Biro.

Armed with these sentiments (but really aiming to save on their real estate bills) more and more companies are letting their employees work from home. In 2005, 1.89 million employees in the country spent at least half of their time working from home. By 2012, that number was 3.26 million, according to Global Workplace Analytics. And last year, a quarter of all employed Americans did at least some work from home, according to the Bureau of Labor Statistics.

But new research shows that there are real downsides to this trend: Working from home is bad for you, bad for your employer, and perhaps even bad for the world. While working from home rarely can be a good thing, doing it too much reduces productivity and happiness, and hampers innovation and creative thing.

A major review of past research on the topic published this month in Psychological Science in the Public Interest found that working from home can be beneficial to employees and employers—but only in small doses. People who telecommute sparingly are happier with their jobs and perform better. But on average, people who telecommute 15.1 hours a week or more (or roughly two days per week) actually report decreased job satisfaction.

The study also found that some of the supposed benefits for working from home don’t stand up to scrutiny. For example, there’s “little empirical evidence to suggest that telecommuting is a generally effective way to mitigate work-family conflict,” the authors write.

Ben Waber, the CEO of Sociometric Solutions, a consulting firm that studies remote working, said that the companies he’s working with saw reduced productivity among remote workers, especially on tasks that involve collaboration.

“If it’s just about you banging out emails or writing a report, sure, you can do that wherever,” Waber said. “But the vast majority of stuff we do at work today—teamwork, not individual work—that is the stuff that really measurably suffers.” For big companies, that decline in productivity can be worth millions of dollars a year.

Waber said there’s no evidence that apps like Slack, a remote-messaging app for workplaces (used by Fusion and other media companies), make employees any more productive than email. And despite the panoply of tools that facilitate remote work, communicating digitally will always be less efficient than talking face-to-face. If I want to ask my editor about an edit while working from home, I have to write an email or message him, wait for him to see it and respond, and then respond again if I have any questions. If we’re right across the office, I can swivel my chair over and talk about it right away.

Remote working has an even more negative impact on innovation and new ideas. According to Waber, you’re more likely to come up with something brilliant if you’re interacting spontaneously with people who have different ideas and areas of expertise, rather than just seeing their avatars in an app. “The technology we have today is not good enough to facilitate those interactions,” he said. It makes sense that some of the biggest tech companies in Silicon Valley, including Google, Facebook and Apple, have discouraged working from home and built headquarters that encourage interaction between people in different parts of the company.

Working from home also negatively impacts employee satisfaction. For one experiment at a major airline, Waber’s company gave each employee a souped-up company ID badge equipped with a microphone, accelerometer, Bluetooth and infrared that tracked where they were going and who they interacted with.

Waber found that employees who frequently interacted with each other reported being happier and were more likely to keep their jobs. “People in tight-knit, face-to-face groups had job satisfaction that was 30% higher,” he said. “When you have a really tight-knit group of co-workers, those people tend to be a lot happier.” On the other hand, the amount of digital communication they did with co-workers had no effect on their job satisfaction.

Working from home can actually exacerbate work stress, if employees work in the same place where they sleep and relax. Working from home “blurs the lines between work and home,” leading people to be less focused while they should be working and stressed out about work during their free time, said Tammy Allen, a psychology professor at the University of South Florida and one of the recent study’s authors. She said employees working from home should create “a specific place at home where you work that has a door, and that door may even be closed during the day if there are others in the house.”

In a 2012 poll, 62% of employees said they found telecommuting to be socially isolating. And “jobs where individuals are most likely to be telecommuting involve sitting in front of a computer,” Allen said, so it makes sense that people working from home would get less exercise than those who have to commute.

Look, everyone has a day once in a while when they’d rather stay home, work in their pajamas, and not interact spontaneously with their co-workers. Enjoying the flexibility to do that every so often is good for your mental health and job satisfaction. And working from home makes a lot of sense for some, like new parents and people with disabilities.

But work is not just a series of tasks to be checked off a list. It’s a social experience that involves trusting, learning from, and teaching other people, and working together to accomplish tasks you can’t do by yourself.

In the work-from-home future some managers envision, none of that will be possible. Co-workers will interact only in virtual spaces and over sterilizing tech platforms. There will be no water cooler, no spontaneous meetings, no ad hoc projects. We will all just be lines in each others’ Google calendars and names in each others’ Slack channels. And while we will have earned some cost savings for our companies, we will have lost an essential part of work: the sense of belonging.

Waber, who works in his company’s Boston headquarters, calls everyone in their Silicon Valley office every day to talk for three minutes. It’s not a formal meeting—they chat about their families and kids, what they’re working on, how their lives are going.

“That’s what gets lost when you work remotely,” he said.