Brain and body can communicate with each other via chemical messengers—and tend to do so constantly. What happens in the brain affects the body—and vice versa. You can choose to think a specific thought or replace it with a different thought. You can choose to act based on the thought or refrain from acting. Peter McWilliams, author of You Can’t Afford the Luxury of a Negative Thought, wrote that a negative mindset is the precursor of all life-threatening illnesses. Negative thinking (e.g., unresolved anger, fear, sadness) appears to be a key contributor to lowered levels of health and wellness. You have the power to choose the thoughts you hang on to and ponder.