This story outlines a University of Utah study testing red light therapy on current football players, the links to chronic brain injury from repeated head impacts, and why researchers think light-based treatment might blunt season-long inflammation and point toward larger trials for veterans, first responders and athletes.
Repeated head impacts can do lasting damage, and that damage shows up as memory problems and, in severe cases, dementia. Chronic traumatic encephalopathy, or CTE, is a progressive disease tied to repeated blows to the head rather than a single incident. Soldiers, athletes and first responders often show the kinds of exposure that raise real concern.
Researchers at the University of Utah designed a small, controlled study to test whether red light therapy could change what happens in the brain across a season. They signed up 26 current football players and split them into two groups: one got active red light, the other used a look-alike device with no light. The treatment was self-administered three times a week for 20 minutes over 16 weeks, mixing convenience with real-world conditions.
The active system used a light-emitting headset plus a device that clips into the nose, aiming to get photons through the skull and into brain tissue. The placebo devices were identical in feel and routine but didn’t emit light. That design matters because it helps keep players and staff from guessing who got the real treatment.
At the end of the season the differences showed up on MRI scans. Players who used the placebo device had increased markers of brain inflammation compared with their baseline scans taken at the season’s start. For players using the red light setup, inflammation didn’t rise across the season, which is exactly the kind of signal researchers were hoping to see.
“My first reaction was, ‘There’s no way this can be real,’” said first author Hannah Lindsey, Ph.D., describing her surprise at the clarity of the results. Skepticism like that is healthy in early work, and it’s the kind of response that pushes scientists to try harder and plan better follow-up trials. Elisabeth Wilde, Ph.D., added her own surprise: “When we first started this project, I was extremely skeptical.”
Previous lab work has suggested that high-powered red light can penetrate the skull and alter inflammation-related molecules inside the brain. That mechanistic idea gives a plausible explanation for the MRI findings, and it’s what motivates researchers to move from pilot studies to more rigorous trials. Still, plausibility doesn’t replace proof, and the team acknowledges limits.
The study’s main limitation is its small sample size, which can leave room for random differences between the treatment and control groups. The researchers were candid about that and said larger randomized clinical trials will be “crucial to back up the results” in bigger populations. Transparent discussion of limits like that is essential when early findings look promising.
More than 100 former NFL players have been posthumously diagnosed with CTE, and that figure keeps attention on sports-related brain injury. Military personnel and first responders face comparable risks from repeated exposures, which is why the researchers plan to widen the net in future work. The goal is to find interventions that protect people who choose high-risk, high-reward jobs and hobbies.
One of the study’s co-authors, Carrie Esopenko, Ph.D., framed the work in practical terms: “We’ve been trying to figure out how to make sports safer, so that our kids, friends and family can participate in sports safely for the long term while they’re involved in activities that give them happiness and joy.” That human-centered view drives the push to translate lab effects into usable protections on the field and in service.
Looking ahead, the team plans a larger randomized controlled trial aimed at people who have persistent symptoms from traumatic brain injury or concussion. They intend to recruit about 300 participants in 2026, prioritizing first responders, veterans and active-duty service members who often carry the long-term burden of repeated brain trauma. A trial that size could give the statistical power needed to confirm or refute the pilot findings.
If future work replicates the Utah results, red light therapy could become another tool to reduce the cumulative harm of repeated impacts. It wouldn’t be a magic bullet, but any intervention that lowers inflammation across a season could change long-term risk trajectories for athletes and service members. Practical, scalable approaches that people can self-administer have obvious appeal for widespread use.
For now the message is clear: pilot data look encouraging, but caution is required until larger trials run their course. The researchers are moving deliberately, aiming to balance excitement with scientific rigor. If the next studies confirm the early signal, the implications for sports safety and veteran health could be significant.
