Inquest into the Death of Jessica Lesley JACKSON

18y · Female·multi-organ failure due to combined effects of environmental exposure (hyperthermia) and dehydration

Jessica Jackson, 18, died from multi-organ failure due to combined hyperthermia and dehydration while weight-cutting for an amateur Muay Thai fight. She lost approximately 9 kg in the final week through water-loading, dehydration, sauna use, and intensive exercise while wearing a sweat suit in 30°C heat. She collapsed during training on the morning of her weigh-in and died 72 hours later in ICU. Key clinical lessons: weight-cutting by acute water loss is extremely dangerous and can cause fatal heatstroke and organ failure, particularly in young athletes unaware of the dangers. Warning signs of critical dehydration (inability to sweat, confusion, weakness) went unrecognised. No medical supervision occurred during her preparation. Clinicians should educate young athletes about safe weight management, recognise that aggressive weight-cutting creates life-threatening vulnerability to heat illness, and advocate for regulatory restrictions on acute water-loss methods in combat sports.