Use the SHIELD acronym to remember the lifestyle habits that will help protect your memory and thinking skills. We are making encouraging progress in finding medications that prevent or even reverse cognitive decline. Until we get there, however, the most powerful way to protect the brain is to live a healthy lifestyle. The healthy habits to include are summed up with the acronym SHIELD, developed by neuroscientist Rudolph Tanzi, co-director of the McCance Center for Brain Health at Harvard-affiliated Massachusetts General Hospital. Here’s what SHIELD means. Sleep at Least Seven Hours a Night As you sleep, your brain flushes out waste material. Also, microglial cells in the brain clean out a toxic protein called beta-amyloid, which can clump together and form the plaques of Alzheimer’s disease. “Microglial cells are like scrubby bubbles,” Tanzi explains. “To get enough cleaning, you need seven or eight hours of sleep that includes dream sleep …