This was especially curious because they began their first paper with a litany of studies demonstrating estrogen’s protective effects on the brain, including its ability to reduce the loss of neurons, improve cerebral blood flow, and modulate expression of the APOE gene.16 Eventually, the WHI investigators conceded that their study was not designed to determine whether women who began taking estrogen at the time of menopause would have a lower risk of the onset of cognitive decline or Alzheimer’s disease a decade or two later.
