Obamacare is incrementally expanding health insurance coverage, but the industry’s fine print is proliferating as well. Many health plans are marketing “wellness” programs as a pathway to a “healthy lifestyle” that rewards good behavior with discounted rates. But the seductive marketing should come with a disclaimer: Wellness programs aren’t for everyone.

The Affordable Care Act encourages providing wellness programs as a form of preventive care, avoiding costly medical burdens down the line. Insurers have expanded these programs to about “94 percent of employers with over 200 workers, and 63 percent of smaller ones,” according to federal research. Insurers could offer 30 percent lower premiums, for example, in exchange for employees’ giving up smoking, or cash for enrolling in an employer-approved gym membership. The Obama administration just issued new rules on using wellness programs in compliance with civil-rights protections, but rights advocates say some groups risk being indirectly penalized or excluded due to subsurface medical profiling.

Exclusionary “wellness” protocols could chafe against two civil-rights protections, the Americans with Disabilities Act and Genetic Information Nondiscrimination Act. Though Obamacare was supposed to prevent the exclusion of “high risk” consumers from coverage due to preexisting health issues, wellness programs seem structured to potentially do exactly that.

In its rulemaking notice the Equal Employment Opportunity Commission (EEOC) stated it did not see a need to mandate more stringent consumer protections, like ensuring workers can challenge the accuracy of screening results.

The National Partnership for Women and Families (NPWF) testified at a Senate hearing last year that lax federal regulations could indirectly enable bias by another name, as insurers “shift costs and withhold rewards from employees with health problems.” The program requirements could expose vulnerable or marginal groups to discrimination, potentially leaving “women, workers of color, older workers and those with disabilities” on a lower tier of care.

“Incentivizing” wellness sounds innocuous enough, but, as NPWF’s senior policy counsel Sara Fleisch Fink explains, “the flipside of a company being able to provide an ‘incentive’ [such as] 30 percent off of the cost of health insurance for participation in a wellness program, is that employees who do not participate will pay 30 percent more for their health insurance.”

Aging workers are especially vulnerable, facing a combination of rising medical risks and approaching retirement, while universal coverage hasn’t yet kicked in through Medicare (a program that was, ironically, designed specifically to prevent the elderly from falling into devastating poverty and sickness).

Privacy advocates worry that wellness programs might be constructed to track “nonvisible disabilities” like cancer or late-emerging mental health problems, in order to limit benefits. Employers might seek to cut insurance costs by indirectly restricting benefits for workers with these conditions (even if those nonvisible disabilities are essentially unrelated to their job performance). David Certner, legislative-policy director for government affairs with the senior advocacy group AARP explains via e-mail that, since nonvisible disabilities tie into aging, wellness program screening could act as a pretext for age discrimination. But “[t]he EEOC’s protections against employers gaining direct access to this information are weak,” Certner says. Insurers, meanwhile, can freely profit off subsurface privacy invasion:

The wellness industry also operates as a large-scale data-mining industry. They collect information on employees and family members [through direct querying of participants, or] through passive means… that allow them to collect health information from one’s other medical providers (e.g. doctors, lab tests, insurance claims, etc.) and “share” it with others.

Refusing to submit to invasive screening could foreclose access to care. In one recent EEOC lawsuit, an employee with the Illinois-based manufacturing company Flambeau alleged he was penalized for refusing a biometric evaluation that would have included “disability-related inquiries and medical examinations” as a condition of participating in an employer’s wellness program. According to the EEOC’s summary, “Flambeau cancelled his medical insurance and shifted responsibility for payment of the entire premium cost to him,” but reportedly did not cut off the coverage of workers who submitted to the screening, who paid just a quarter of the premium costs.

EEOC lawyer John Hendrickson argued, “Having to choose between complying with such medical exams and inquiries, on the one hand, or getting hit with cancellation or a penalty, on the other hand, is not voluntary and not a choice at all.” (Flambeau initially won the case by contending that its “voluntary” program could legitimately require biometric examinations; the EEOC has since appealed).

Actuarially driven discrimination can be as technologically sophisticated as it is socially regressive. Some programs rely on arbitrary formulas like the Body Mass Index (BMI)—a metric derived from height and weight used to bluntly assess obesity—instead of more holistic health examinations.

Insurers can’t be blamed for using BMI as a rough indicator of obesity-related risks within an insurance pool. But for an individual worker, such as the diabetic retiree with asthma who might exceed her target BMI but is not in a position to crash diet to achieve a “wellness” benchmark, how would making her doctor’s visits more costly make her healthier?

The very concept of “incentives” raises questions of medical efficacy. How would insurers even measure the long-term “success” of linking premium rates to a weight-loss program? As NPWF’s testimony pointed out, “There is scant—if any—empirical evidence that monetary rewards can result in sustained weight loss. Crucially, there is no independently evaluated research demonstrating that linking the cost of employer-sponsored insurance to certain biometrics has an impact on health outcomes.”

A possible side effect of biometric surveillance, the group argues, is anxiety: Arbitrary health assessments could lead to “more people refusing testing and treatments they need for fear employers and insurers will use the information against them,” and, while premium rates continue to inflate in general (worker contributions to insurance plans have jumped over 80 percent since 2005), the wellness gap could impose “higher health insurance costs for the consumers who can least afford to pay.”

Wellness programs are routinely marketed as a win-win for workers, employers, and healthcare providers. But the power of predictive data to promote “healthy habits” can also be manipulated to systematically exclude undesirable insurance consumers. When “rewards” for good health punish the vulnerable, this ounce of prevention may be a cure worse than the disease.