The short answer is “yes,” through a process called neurogenesis. Unsurprisingly, one of the primary areas for neuron growth is the portion of the brain called the hippocampus, which is responsible for memory and learning. Neuroscientists estimate that we generate approximately 700 neurons there a day, and that by middle-age, we’ve replaced all of the hippocampic neurons we were born with with new ones.
Now for the elephant in the room regarding neurogenesis: can we control it? Again, the answer is yes, to a certain extent. Indeed, neuroscientific studies show that activity and diet directly impact the brain’s ability to generate new neurons. Examples of activities that improve neurogenesis include running, chewing (one study showed that a diet with crunchier foods promoted neurogenesis) and even sex (unless it led to sleep deprivation, which would neutralize the act’s otherwise neurogenetic potential). In terms of diet, blueberries, omega-3 fatty acids (from fish) and flavonoids (from dark chocolate) all promote neurogenesis. Conversely, stress, sleep deprivation, and alcohol consumption (unless it’s red wine in moderation, as this contains resveratrol, which promotes neuron survivability) have all been shown to decrease neurogenesis.