While some studies find no macroscopic structural changes or long-term cognitive decline specifically tied to amateur soccer heading, a substantial body of evidence links repetitive subconcussive head impacts, such as heading a football, to neurodegenerative processes, tau pathology, and chronic traumatic encephalopathy (CTE).
The retrieved literature contains multiple studies and reviews detailing the pathophysiological mechanisms (tau aggregation, glial reactivity, neuronal loss) and clinical evidence linking repetitive head impacts and soccer heading to chronic traumatic encephalopathy (CTE) and cognitive or learning impairments. Although a couple of studies report no significant association with macroscopic brain volume changes or long-term cognitive impairment in specific cohorts, the weight of evidence including neuropathological case reviews and risk analyses strongly supports the connection between heading and long-term brain damage.