Only one of the 90 different workplace wellness offerings appeared to boost well-being

There are some limits based on the methodology but this a robustly large study.  From Most workplace wellness programs don't boost well-being by Ernie Mundell.  

Employees at many companies are urged to take advantage of free wellness programs focused on mindfulness, life coaching, better sleep and many other issues.

Too bad most won't actually boost their well-being, a new study of over 46,000 British workers finds.

Only one of the 90 different workplace wellness offerings appeared to boost well-being: Getting employees involved in charity work or volunteering, the researchers found.

The findings "pose a challenge to the popularity and legitimacy of individual-level mental well-being interventions like mindfulness, resilience and stress management, relaxation classes and well-being apps," concludes the study's sole author, William Fleming. He's a fellow at Oxford University's Wellbeing Research Center.

As with any policy or program, there is what can work which is always distinct from what does work.  In other words, perhaps the health programs are effective but they are not well designed, or communicated, or incented to participate, etc.  

Or, possibly, the programs simply don't work.