Epidemiological research has demonstrated a positive correlation between tofu consumption and brain atrophy in men. Because correlation does not prove causation, correlation-based hypotheses should be tested against the availability of possible causal mechanisms. While it has been shown that the soy phytoestrogen genistein inhibits neuroprotective functions in cell cultures, recent in-vivo findings strengthen the case for a possible causal mechanism of soy-induced neurodegeneration. The author suggests possible responses to this data regarding soy consumption.