The US National Institutes of Health (NIH) is considering limiting postdoctoral researchers to a maximum of five years of agency funding. The idea is an attempt to improve working conditions and career prospects for young researchers, but has sparked heated debate about its potential impact.

Some researchers say the five-year limit and other restrictions the agency is considering could perpetuate inequities in the biomedical workforce and deter researchers from staying in academia. Rigid time limits also send the message “that science needs to be done very quickly,” says Anna Cliffe, a virologist at the University of Virginia School of Medicine in Charlottesville. “Science is not always fast.”

The Bethesda, Maryland-based NIH released a request for feedback on the ideas on July 25, acknowledging the concerns raised so far. The goal is to “accelerate the career transition of these researchers into thriving biomedical research careers,” says a spokesman for the agency’s Office of Extramural Research.

Replenishing the talent pool

The NIH request comes at a time when biomedical graduate students are increasingly choosing positions in industry, which has led many principal investigators to raise concerns and say they are having difficulty filling postdoctoral positions. To find solutions, the agency asked a working group of NIH researchers and outside scientists what the agency could do to support talented postdoctoral researchers.

In a report submitted in December The panel recommended the report, NIH-funded postdoctoral fellows receive a minimum salary of $70,000 with annual adjustments for inflation. Since then, the agency has moderately increased postdoctoral salaries and said it intends to reach recommended targets no later than 2029, funding permitting.

The panel also recommended a five-year limit on funding for postdoctoral positions and changes to a key grant called K99, which is designed to help postdocs find their feet as they search for faculty positions. Currently, researchers can apply for a K99 if they have less than four years of postdoctoral experience. The panel recommended limiting applications to people with less than two years of experience.

Instead of continuing in that role, senior postdocs should be promoted to an intermediate position, sometimes called a 'research scientist' or 'lab assistant,' which comes with higher salaries, says Shelley Berger, an epigeneticist at the University of Pennsylvania in Philadelphia who co-chaired the NIH panel. The working group recommended that the agency expand support for these interim roles within one year of the report's release.

The panel recommended these changes to encourage researchers to move into more permanent positions rather than being stuck in postdoctoral positions whose salaries don't match their skills, says Donna Ginther, a member of the working group and an economist at the University of Kansas in Lawrence who studies the composition of the scientific workforce. “You don’t want people to spend their most productive years in a postdoc,” she says.

But the agency has not yet implemented or sought feedback on the recommendation for additional funding for interim positions, Berger says. This lack of action is “very disappointing,” says Berger, adding that it would be logical to implement this in parallel with the five-year limit for postdocs.

Funding equalities

Encouraging senior postdocs to move into positions that offer the salaries they deserve is a noble goal, says Tiffany Ho, a clinical neuroscientist at the University of California, Los Angeles. But she fears that without additional funding for such positions, only well-equipped laboratories would be able to attract and retain such people as research scientists. That would perpetuate disparities between the best-equipped labs and those with more modest support, she says.

The limit could also prevent researchers from pursuing multiple postdoctoral positions in different labs, as some do. Cliffe, who studies herpes viruses, says the border would have prevented her from taking a second postdoctoral position in a neuroscience lab that was "completely different" from the field in which she trained. “But it has allowed me to be creative, combine my expertise and build a truly new area of ​​research,” she adds.

Additionally, cutting the eligibility period for the K99 in half would discourage international scientists, Ho says, since it is the only NIH funding specifically for postdoctoral support available to non-U.S. citizens. “U.S. citizens would be strongly preferred because they already have the networks and communities to get started right away,” she says. This could counteract NIH's efforts to train researchers from underrepresented groups in the biomedical field, says Camila Coelho, a virologist at the Icahn School of Medicine at Mount Sinai in New York City. “You’re promoting a system where you favor people who are already favored,” she says.

The NIH hopes researchers will respond to its request for feedback "so we can learn more about these concerns" and "ensure a sustainable, diverse future workforce," the agency's spokesperson says.

Stagnant budget

These proposals come at a time of tight budgets for the agency: The NIH budget for 2024 was essentially flat at $47.1 billion, a net loss when inflation is taken into account, says Berger, and the 2025 budget is expected to be about the same. Increasing postdoc salaries will likely mean cuts need to be made elsewhere, Ginther says.

Ho says the precarious situation for postdocs should spark a discussion in the scientific community about how to invest more in "early researchers, even if it would probably come at the expense of researchers like me." A proposal was made in 2017, but was not implemented would have limited the amount of NIH funding awarded to an individual scientist. “If we as a community can decide that this is OK because we are investing in the future, maybe that is a viable solution,” Ho said.