But now, my boss is pushing everyone to sign up (I think he gets some kind of prize if we all join), which involves filling out forms that ask a lot of detailed medical questions. Everyone here is also required to attend information sessions about the program. Is there a graceful way to refuse? — Thanks But No Thanks

Dear TBNT: Because laws governing corporate wellness programs are so complicated — more about that in a minute — you’re actually asking three different questions here. So let’s start with the easiest one, about those information sessions. The short answer is, employers can make the meetings mandatory, even though signing up for the wellness program is not.

“When people hear the word ‘mandatory’, they often run for the hills,” notes Nicholas Park, a consultant with employee-benefits firm Corporate Synergies. “What ‘mandatory’ means in this context is, the company can require you to receive information.” So yes, if attendance is required, then go.

What you do with the information you get, however, is entirely up to you. There has been so much confusion about this that even employers who thought their wellness programs were in compliance with federal law have been successfully sued by the federal Equal Employment Opportunity Commission, so the EEOC keeps proposing new regulations intended to clear up the fog. In April, a new set of not-yet-finalized rules reiterated that wellness programs are strictly voluntary, and employers are prohibited from requiring anyone to join.

You don’t say exactly how your boss is “pushing” you to sign up. But managers need to know that — thanks to a patchwork of overlapping federal and state laws and regulations, notably including the Americans with Disabilities Act (ADA) — it’s illegal to take any “adverse employment action” against an employee who chooses not to participate in a wellness program.

So if all your boss is doing is encouraging you to think about it, no harm done. Just smile and change the subject. But if, for example, you’re denied a promotion and you think that it’s because you declined to participate, it’s time to speak to someone in HR. Breaking the law “risks having the whole company’s wellness program shut down, which is not a risk any employer wants to take,” Sheri Snow points out.

Snow manages several wellness efforts at American Cast Iron Pipe, a midsized manufacturer (like your employer) in Birmingham, Ala., that makes pipe for water systems and the oil and gas industry. American’s various wellness programs are decades old, and have been so successful that the company was among a handful of case studies in a new white paper on best practices by the Johns Hopkins Bloomberg School of Health and the Transamerica Center for Health Studies.

Yet, even with over 80 percent of American’s employees signing up, Snow sometimes hears concerns like yours from people who worry that their medical information won’t be kept private. “One employee absolutely did not want anything about her health entered into any kind of electronic system,” Snow recalls. “So she filled out the forms on paper, and I kept them in a locked filing cabinet in my office, and discussed the information with her privately, one on one.

“That meant I couldn’t include any of that information in the aggregate data,” Snow adds — which brings us to the third aspect of your question. To protect people’s privacy, the laws covering these programs dictate that employers (and outside vendors) aggregate the health information they gather into an anonymous mass of data, so that no individual employee is recognizable.

Employers also must explain how that works. “The Affordable Care Act requires your employer to give you a policy document that clearly spells out how your medical information will be used, who will see it, and in what form,” notes Nicole Baldwin, an attorney at Carothers DiSante & Freudenberger in San Diego who has a lot of experience in this area. “Often it’s in a handbook. If you haven’t seen that, you should ask to see it.”

But if that doesn’t reassure you, remember that “these programs are strictly voluntary, and you absolutely have the right to opt out,” says Dan Kuperstein, general counsel and senior vice president at Corporate Synergies. “Just say ‘no thanks’, and stick to your guns.”

Good luck.

Talkback: If your employer offers a wellness program, have you felt pressure to participate in it? Leave a comment below.