What was the cause of Simone Weil's death as noted in the memoir, Waiting For God?

Weil wrote extensively, but the majority of her work was published posthumously due to her untimely death in 1943 at the age of 34. Weil battled sickness, depression, and general frailty throughout her life and the exact cause of her death remains controversial. She died of malnourishment in England, but it is unclear whether this was due to illness or voluntary starvation. She remains an important, albeit understated figure in the history of Christian mysticism and Western philosophy.