A recent study of 302 amateur soccer players revealed that heading the ball provokes an immediate rise in blood biomarkers associated with neural injury. The findings, published in JAMA Neurology, tracked these proteins before and after matches, showing a clear dose‑response relationship between the number of headers and biomarker concentration.
The hidden cost of a goal
High‑impact headers from distance produced the most pronounced spikes, and statistical significance emerged after just over two headed contacts. Earlier imaging projects from Columbia University, released in 2025, identified the boundary between white and gray matter in the cerebral cortex as the most vulnerable region to repetitive heading.
The proteins S100B and p‑tau217, which the researchers measured, serve as indicators of glial stress and tau pathology respectively, linking heading to early signs of brain trauma. S100B is a calcium‑binding protein found specifically in glial cells, while p‑tau217 is a phosphorylated protein associated with Alzheimer's disease and traumatic brain injury.
Dr. Peter Theobald, a co‑author of the paper, noted that even a modest number of headers can alter these markers within 24 hours, though they typically normalize after a day or two. The biomarker levels returned to normal within 24–48 hours after the match.
The results suggest that repeated heading, even at the recreational level, may carry a hidden cost for brain health, prompting calls for additional research and possible rule adjustments in the sport. Former professional soccer players already face a two‑ to three‑fold increased risk of neurodegenerative disease, underscoring the need for broader safety considerations across all levels of play.