The workplace wellness industry now supports over 5,600 vendors and generates a total revenue of over $8 billion a year in the US alone, a four-fold increase since 2011, all to help make employees healthier and more productive.

Workplace wellness has been a significant driver of core smart building technologies such as human-centric lighting, air quality sensors and environmental control measures. However, one recent study suggests that workplace wellness initiatives may actually have little or no impact on employee health or productivity.

“Our rigorous study of a comprehensive workplace wellness program concludes that it didn’t change employees’ behavior or health care costs in the first year. Employees who took part didn’t become healthier or more productive, and were not more likely to go to the gym or run in a local race. Total health care costs didn’t drop, either,” says Damon Jones is an Associate Professor at the University of Chicago, Harris School of Public Policy.

The study by Jones and his team ran a large-scale randomized controlled trial (RCT) to identify if the program had any impact on health and well-being, productivity, and health care spending. Participants of the iThrive workplace wellness program at the University of Illinois were offered a biometric health screening and complete an online health risk assessment. Then encouraged to participate in an array of wellness activities such as recreational exercise classes, a tobacco cessation hotline, and an online, self-paced wellness challenge. Monetary incentives were also offered with a random variation to assess the effectiveness of such measures.

“One year later, when we compared the control group to the iThrive group, we found that the program didn’t lead to healthier employees or reduce health care costs. The program’s failure to improve health outcomes or reduce costs was likely because employees who were interested in participating in the workplace wellness program were already quite healthy,” suggests Jones in an article on the study in Scientific American.

“A year before the program began, people who ultimately chose to participate in iThrive were already more likely to visit recreational facilities on campus or to participate in a community running event. On average, they already had incurred $1,373 less in medical expenses over the previous year compared to employees not interested in the program. Participants were also less likely to have extremely high medical expenses and were higher-earners, on average.”

The results, and subsequent analyses, suggest that workplace wellness programs simply attract employees that are already health conscious, rather than making less healthy employees healthier. Jones suggests that other studies of workplace wellness programs likely suffer from selection bias because many do not use RCT methodology, but he is also the first to admit that his one year study has not gathered enough information to be certain of the results.

“We emphasize that at this point we’ve only observed one-year impacts from this workplace wellness program,” says Jones. “In the next phase of our study, we will collect biometric outcomes and follow up with participants to track potential changes in health behaviors and costs for up to 4 years following the intervention. That investigation may uncover longer-run impacts that might not have registered in the first year of the study.”

Employers may actually be guilty of workplace discrimination against those employees that are less healthy or less able to participate in such programs. The American Association of Retired Persons (AARP) even took the case to court, arguing that participation in workplace wellness programs is not truly voluntary if employees are offered substantial monetary rewards conditional on participation. The District Court ruled in AARP’s favor, and the Equal Employment Opportunity Commission (EEOC), a federal agency that enforces civil rights laws against workplace discrimination, removed a regulation that allowed employers to incentivize participation in workplace wellness programs by up to 30% of the total cost of an employee’s health insurance coverage. Thereby neither permitting nor prohibiting employer-provided incentives and leaving the future of workplace wellness uncertain.

While Jones’ research is intriguing, the overwhelming majority of studies into workplace wellness support its ability to make employees happier, healthier, and more productive. The positive evidence for workplace wellness has been so compelling that the WELL Building Institute was created by a global community of wellness and employment professionals who believe in workplace wellness. So compelling that employers have consistently chosen to invest in wellness programs and believe they experience the benefits of healthier, happier, more productive employees.

Jones’ study measures success in large part by participation in wellness programs, which itself skews results. Other studies have demonstrated that such initiatives lead to less absenteeism and reduced overall healthcare costs for the employer. Then, when attempting to identify relatively intangible benefits like worker focus, collaboration within the workplace, or employee loyalty, for example, much more extensive study is required before writing off the entire movement.

“Given the large amount of investment in workplace wellness programs, it’s worth establishing a rigorous understanding of the real impacts of these programs,” Jones admits after the first year of research on the topic. “Our study finds that the return on investment is likely low in the short run; future results from our study will shed light on whether benefits will emerge in the long run.”