For a long time, the elderly with dementia were believed to be cursed, or to have an infection like syphilis (because the symptoms of syphilis can be similar). So the word dementia was considered pejorative, used as an insult. In fact, when I first told my kids I was writing this book, they asked if it was about dementors, the dark, soul-sucking creatures from Harry Potter. The idea that dementia, which is not a specific disease but a group of symptoms associated with memory loss and poor judgment, is sometimes thought of in such negative ways is worth addressing briefly here.
It is true that scientists and doctors use the word clinically, and it is also true that patients and their loved ones don't always know what to make of it, especially when they first receive the diagnosis. It is too imprecise, for one thing. Dementia can be a spectrum, ranging from mild to severe, and some of the causes of dementia are entirely reversible. Alzheimer's disease, which accounts for more than half the cases of dementia, gets nearly all the attention, and as a result, the terms dementia and Alzheimer's are often used interchangeably. They shouldn't be. The word dementia, however, is steeped in our common vernacular, and so is the association with Alzheimer's disease. In this book, I use both terms with the hope that the conversation, and the words we use to describe the broad condition of cognitive decline, will shift in the future.
I believe there has been an overemphasis on Alzheimer's disease as a way to talk about this broad condition, and it has further fueled a widespread sense of fear that memory loss is inevitable as we get older. Perfectly healthy people in their thirties and forties are alarmed about the implications of common memory lapses, like misplacing their keys or forgetting someone's name. That is a misguided fear, and as you will learn, memory loss is not a preordained part of aging.
As I started traveling the world talking to people about this book, I realized something else extraordinary. According to an AARP survey of Americans aged thirty-four to seventy-five, nearly everyone (93 percent) understands the vital importance of brain health, but those same people typically have no idea how to make their brains healthier or that achieving such a goal is even possible. Most believe this mysterious organ encased in bone is a black box of sorts, untouchable and incapable of being improved. Not true. The brain can be continuously and consistently enriched throughout your life no matter your age or access to resources. I have opened the black box and touched the human brain, and I will tell you all about those extraordinary experiences in this book. As a result of this training and decades of additional learning, I am more convinced than ever that the brain can be constructively changed—enhanced and fine-tuned. Just consider that. You probably think of your muscles that way—even your heart, which is a muscle. If you are reading this book, you are someone who is probably already proactive about your physical health. It is time to realize the same is possible with your brain. You can affect your brain's thinking and memory far more than you realize or appreciate, and the vast majority of people haven't even begun to try. Keep Sharp is going to help you design your own "sharp brain" program, which you can easily incorporate into your daily life. I have already done it myself, and I am excited to teach you to do it as well.
As an academic neurosurgeon and a reporter, a big part of my job is to educate and explain. I have learned that in order for my messages to stick, explaining the why of something is just as important as the what or the how. So throughout this book, I explain why your brain works the way it does and why it sometimes fails to deliver what you'd hoped. Once you understand these inner workings, the specific habits I encourage you to adopt will make sense and more likely become an effortless part of your routine.
Truth is, even when it comes to our general physical health, there is very little explanation in public discourse of how our bodies actually work and what makes them work better. Even worse, there is a lack of agreement among medical professionals about the best foods to eat, the types of activities we should pursue, or the amount of sleep we really need. It is part of the reason there are so many conflicting messages out there. Coffee is practically a superfood one day, and the next it's a potential carcinogen. Gluten is hotly debated continuously. Curcumin, found in turmeric, is touted as a miracle brain food, but what does that really mean? Statins seem to have a split personality, at least in the research circles: Some studies propose that statins lower risk for dementia and improve cognitive function, and other studies suggest the exact opposite. Vitamin D supplementation is constantly under fire too; some people swear by it, but study after study shows no benefit.