If signed into law, the PHIT Act would amount to a tax break for gym memberships, fitness classes, and the purchase of certain “safety equipment” related to fitness (it’s unclear exactly what kind of equipment and activity would qualify under the legislation’s purview—although certain things like horseback riding and golfing wouldn’t pass muster). Just how much of a break might one get? Qualified expenses couldn’t exceed $500 for an individual or $1,000 for a joint household return.

It’s an open question whether or not the proposal will ultimately pass. But it’s already drawing some raised eyebrows from critics who say it would essentially benefit wealthy (and relatively healthy) people who already go to a gym or take fitness classes while doing little to incentivize the vast majority of Americans to exercise more.

Why is that? For one thing, the measures are centered around health savings accounts (HSAs) and flexible savings accounts (FSAs)—financial tools that are ostensibly meant to pay for out-of-pocket medical costs and that many taxpayers don’t necessarily have access to.

But the deductions would also have to be itemized under the existing measure. For context, less than a third of all taxpaying households itemize, and they skew heavily toward the wealthiest Americans. And while preventive wellness programs have become a regular cottage industry in the public health sphere, the evidence supporting their overall effectiveness is, at this point, still decidedly mixed.

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