From dieting to sleep apnea, it seems our day-to-day lives may affect our brains more than previously believed.We won’t name names, but certain major organs—ahem, the heart, liver and kidneys—seem to have been hogging the research spotlight when it comes to how they’re affected by diet and overall health. But judging from several recent studies, our brain doesn’t get a free ride.”We’ve managed to treat those diseases, such as heart disease and cancer, that would otherwise kill us,” says Dr. Charles DeCarli, M.D., the director of Alzheimer’s Disease Center at the University of California at Davis in Sacramento and a fellow of the American Academy of Neurology. “As we live longer, the brain becomes more and more important because that’s what fails as we age.”QUIZ: How Does Your Health Impact Your Life?Alzheimer’s has been the primary brain-related heavy-hitter that we worried about, but researchers have revealed that there are more brain matters to be concerned about.The most freaky and somewhat disturbing new study found that certain neurons in the brain actually begin to eat themselves—yes, folks, eat themselves—when the body is in starvation mode.Although it sounds like something straight out of a horror flick, researchers found that autophagy, or the act of self-eating, occurs in certain hunger-inducing neurons within the hypothalamus to give the body a head’s up that it’s time to eat.It’s important to keep in mind that the study, published in the August 2011 issue of the journal Cell Metabolism, was only conducted on mice, so any research on self-cannibalism within the human brain has yet to be reported. The jury is still out on whether or not a human brain will turn on itself in the same way (or even if it’s necessarily a bad thing), but it’s not too far-fetched to imagine what might happen if you frequently crash diet.If the potential for self-cannibalism doesn’t warrant paying more attention to your noggin, how about the fact that unhealthy habits can bring on brain shrinkage?According to a recent study published in Neurology, the medical journal of the American Academy of Neurology, smoking, high blood pressure, diabetes and being overweight in middle age may cause the brain to decrease in mass. What’s more, this shrinkage could lead to cognitive decline such as Alzheimer’s up to a decade later in life.”These factors appeared to cause the brain to lose volume, to develop lesions secondary to presumed vascular injury, and also appeared to affect its ability to plan and make decisions as quickly as 10 years later,” study author Dr. DeCarli said in a statement.If you’re still convinced that the brain should take a back seat to other organs, consider this: A new study by researchers at The University of Alabama found a key link between stroke incidence and cognitive decline. Residents of the Stroke Belt—Alabama, Arkansas, Georgia, Louisiana, Mississippi, North Carolina, South Carolina and Tennessee—who were over age 45 experienced an 18 percent higher incidence of cognitive decline than those in the rest of the United States.STUDY, EXPLAINED: Cognitive Decline in the Stroke Belt“The brain and the body are tied together,” says Dr. DeCarli. “This makes a whole lot of sense, particularly when it comes to vascular health. The brain receives blood vessels, just like the heart and kidneys, and so it suffers the same kind of consequences.”Yet another new study, published in the Journal of American Medical Association, may lead to some sleepless nights: It found that sleep apnea—a serious sleep disorder in which you intermittently stop breathing during the night—may result in up to 85 percent higher risk of developing dementia or mild cognitive impairment within a five-year period.QUIZ: What’s Your Sleep Quality?Elderly women who experienced 15 or more sleep apnea events per hour of sleep had the highest risk of cognitive impairment due to oxygen deprivation.So while we don’t want to downplay the importance of those other organs (we’re talking to you, heart), this torrent of new brain-related studies may signal that we’re finally diving deeper into important neurological research, revealing how our health can harm—or help—our brain.