The doctor who performed the post-mortem on Claire Squires, who died during last year's London Marathon, has told an inquest that she died of heart failure, likely complicated by the supplement DMAA.
The caffeine-like stimulant was in the runner's drink, and has since been banned in the UK.
"DMAA causes increased heart rate. On the balance of probability I think the DMAA was a contributing factor to her death' Dr Van Der Walt said.
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