While many believe the brain to be relatively unchanging from adulthood until death, the truth is that the human brain, depending on the mental challenges and physical nutrition we give it, is subject to considerable change. The brain’s tissues depend on regular nutrition and mental challenges to function at their fullest capacity.
As we age, blood flow to the brain naturally begins to decline. Our hearts age as well, gradually becoming less able to deliver oxygen-rich blood to all parts of the body. To compensate, our brains respond physically by growing new nerve endings. Neuroplasticity is the term we give to these changes, which occur frequently during physical development (infancy, childhood, and adolescence). These changes continue into adulthood and old age, and periods of increased neuroplasticity often occur after head trauma as the brain attempts to find new pathways for information.
Though it may be difficult to imagine our brains as being mechanical, our memories are stored in physical structures called neural networks. As we develop, learn, and age, these neural networks change to accommodate new information. A key part of neuroplasticity, our ability to grow new neural networks, decreases over time. Fortunately, environment plays a crucial role in managing this phenomenon. This is why mental challenges are so important to overall brain health as we age: intense intellectual effort can reduce negative physical changes in the brain. Things like learning a new language, reading challenging books, creative writing, drafting plans for woodworking, and solving puzzles will help you both generate new neural networks and retain the ability to construct them efficiently in the brain.
When it comes to brain health, proper nutrition goes hand-in-hand with mental challenges. Omega-3 fatty acids, found primarily in fish and nuts, help to maintain the myelin sheaths found in the brain’s neurons. Think of myelin as insulation for wire: if the insulation breaks down, the connections between the brain’s neurons can cause serious problems with memory and overall function. This is why zero-fat diets are terrible for brain health: such diets literally starve the brain of the necessary fats to keep the brain functioning at high capacity. Blueberries provide antioxidants that reduce the stresses oxygen exposure can have on the brain (as well as the heart). Seeds and nuts are high in Vitamin E and other helpful nutrients, but steer clear of nuts or nut products (like peanut butter) that have been altered with hydrogenated oils, which can cause harm to the heart. Regular cardiovascular exercise serves as an excellent supplement to proper nutrition, given that it helps keep the heart healthy enough to pump blood efficiently, reducing the decline in blood flow to the brain as we age.