Time after Time: Environmental Influences on the Aging Brain (Elizabeth Grossman, Environmental Health Perspectives, Sep. 2, 2014)
Today we review a paper that analyses the impacts of exposure to outdoor air pollution as it relates to the health of the elderly portion of the population - those over 80 are projected to quadruple since 2000. While exercise and intellectual stimuli can keep the brain healthy and may reduce the onset of Alzheimers, exposure to lead or organic pollutants may decrease the defensive mechanisms and increase vascular problems.
“the population of Americans aged 65 and older is expected to double between 2010 and 2050, and by midcentury the proportion of the human population made up of people over age 80 is projected to have quadrupled since 2000”
“the brain is capable of generating new neurons and other functional brain cells even during advanced age. There is also evidence that the older brain can respond quickly and positively to external influences such as physical exercise and intellectual stimulation …converging evidence suggests exercise benefits brain function and cognition across the mammalian lifespan, which may translate into reduced risk for Alzheimer’s disease in humans.”
"The two most vulnerable periods for the brain…are early in life, when the organ is first developing, and later in life, when the body’s defenses and compensatory mechanisms begin to falter”
“declining defense mechanisms may magnify vulnerability to contemporary environmental exposures”“lead that has accumulated in bones can be mobilized over time as part of the aging process, resulting in exposures that adversely affect adults’ cognitive skills later in life”
“exposure to persistent organic pollutants including dioxins and certain polychlorinated biphenyls, halogenated flame retardants, and pesticides can produce hormonally mediated effects that promote obesity and diabetes, which increase risk for vascular health problems”
“Chemical exposures can produce health effects that set the stage for neurological disease and disorders, while physical and intellectual exercise foster brain flexibility and a healthy cognitive reserve”