Some health experts are warning that insurance rates could rise significantly for people in the individual market who are between 50 and 64, or have a pre-existing condition - once states start taking advantage of new flexibility granted this week by the Trump administration.
States can now apply for a waiver to the Affordable Care Act, which would allow the sale of cheaper, so-called "skinny" plans that do not offer the minimum benefits required under the ACA.
Sabrina Corlette, a research professor at the Georgetown University Center on Health Insurance Reforms, says the new plans will be able to reject people because of their age or health status.
"They can deny people outright if they have a health condition that they don't want to cover," she points out. "They can cap your benefits. They cannot cover major benefits like prescription drugs or preventive care. They are really completely unregulated."
Supporters of the new federal guidance say the less comprehensive plans will encourage more young, healthy people to buy insurance.
Each state will still be required to offer more comprehensive, ACA-compliant plans, but Corlette predicts the pool of people left in them will be older and sicker, which will lead insurance companies to raise rates or leave the ACA market altogether.
So, the battle over the ACA now moves to the state level.
Corlette adds that red states such as Utah, which has sued to invalidate the ACA, may be more likely to seek a waiver that would undermine the program - and that could hurt people approaching retirement.
"If you are between 50 and 64, the affordability of insurance, if you have to buy it on your own, is going to vary," she explains. "And there are some states, in the name of greater choices - particularly for young and healthy people, you know - the trade-off is that insurance becomes more expensive for people who are older, who have pre-existing conditions."
If states are granted a waiver under the new rules, the new types of plans could come onto the market in 2020.