For decades, Dr. Dean Ornish has been talking to anyone who will listen about the power of lifestyle changes to avoid some of the chronic diseases that lead to the most drastic health-care costs and consequences: heart disease, diabetes, obesity, and cancer. In 2024, he extended his work to show that a vegan diet, daily aerobic exercise, a meditation and stress-reduction practice, and social engagement can together slow the progression of another increasing health concern as the population ages—Alzheimer’s disease.
In his study, published in the journal Alzheimer’s Research & Therapy, people who were diagnosed with mild cognitive impairment or early Alzheimer’s disease and adopted Ornish’s program for 20 weeks showed significant improvements in three of four standard measures of their cognitive function, compared to another group that maintained their current habits and recorded worsening scores. The results don’t surprise Ornish. “I have a unifying theory that many different chronic diseases share the same underlying biological mechanisms,” he says. “That’s why what is good for the heart is good for the brain—these same mechanisms affect different conditions, and lifestyle choices can make them better or worse.”