A major study by Auckland University has found that playing high level rugby increases the likelihood of developing Alzheimer's and other brain diseases.

Former male high-level players in New Zealand face a 22% increased risk when compared to men in the general population.

NZ Rugby's General Manager Steve Lancaster told Heather duPlessis-Allan that, 'the research that's just been published actually makes it very clear that it doesn't establish causation'

He believes that although there is correlation, there are too many external factors in play. 

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