With frustrating vagueness reflecting the limitations of our knowledge, the Mayo Clinic website reports Alzheimer’s disease is caused by “a combination of genetic, lifestyle and environmental factors.” Newly published research provides evidence that one of those environmental factors may be secondhand cigarette smoke. Researchers in Hong Kong report chronic exposure to smoky air apparently affected the brains of rats. “These changes might serve as evidence of early phases of neurodegeneration,” they write in the online journal PLoS ONE, “and may explain why smoking can ... Read More