Over the past century, as physical health has improved and lifespan lengthened, a pivotal question has emerged: How can we match "brainspan" to lifespan, so that we do not just live for a long time, but live fully?
Scientists are working to answer this question. They are exploring a broad range of possibilities to determine how we can keep our brains fit and healthy—at any age.
We've conducted an investigation into the science of brain fitness to determine the strategies that hold the most promise for helping us stay sharp throughout life. Read on to find the verdicts we've drawn from available scientific evidence.
The Question: Does what we eat affect brain function?
The Verdict: Many scientists believe that eating healthily may be as good for the brain as it is for the body—but figuring out what is the best "brain food" is still a matter of research. So far, fish seems to top the list.
Fish studies—A 2005 study published in the Archives of Neurologyshowed that normally aging people who ate fish once a week experienced a 10% slower decline on cognitive tests. A previous study in the same journal concluded that people 65 and older "who consumed fish once per week, or more, had 60% less risk of Alzheimer disease compared with those who rarely or never ate ﬁsh." Some scientists think the omega-3 fatty acids in ﬁsh make it brain healthy by reducing inﬂammation. This evidence is not yet conclusive, but suggests a possible connection.
Vitamin studies—Over the last several years, vitamins have been the central focus of several studies about brain health. These studies have conﬂicting results.
- Some studies have suggested that getting enough folate and vitamins B6 and B12 can stave off decline and dementia. Yet a more recent study has shown that too much folate can increase the risk of cognitive decline.
- While some studies suggest that antioxidants, especially vitamins E and C, can combat the oxidative stress of older brains, others show that consumption of these vitamins makes no difference.
Other foods and supplements—Green tea, gingko biloba, blueberries, spinach, apple juice, garlic—the beneﬁts for cognitive health of these foods and others are continuing subjects of scientiﬁc study.
The Question: Can "brain exercises" keep the brain in shape?
The Verdict: The brain's natural neuroplasticity—its ability to change its functioning—holds real potential for improving brain ﬁtness as we age. The correct brain exercise might help your brain reach top form—and reduce the incidence of pathological problems like Alzheimer's at the same time.
The Evidence:Over the last twenty years, studies have shown—in one brain system after another—that the brain retains its natural plasticity throughout life. Engaging neuroplasticity in adulthood requires intensive, repetitive brain exercise. It's probably not surprising to you that brain exercise can help keep the brain ﬁt: "use it or lose it" has inspired many people to do crossword puzzles and other activities to stay sharp. Studies have shown that learning to perform new and challenging activities can engage the brain's natural plasticity to make positive changes.
Recently, scientists have begun to take "brain ﬁtness" exercises to a higher level. Highly targeted, scientiﬁcally designed neuroplasticity-based exercises are now available for personal use.
The Question: Does physical exercise keep the brain healthy?
The Verdict: Physical exercise isn't just good for the body—it's good for the brain. Scientists continue to debate why this is the case and what types of exercise are most appropriate. Continuing research, much of it supported by the National Institute on Aging, should help to shed light on the types and qualities of physical exercise that can help keep the brain ﬁt. And for those of you who haven't started exercising yet, take heart: studies suggest that picking up an exercise program at any age and in relatively small doses may help.
The Evidence: A recent article in the Annals of Internal Medicine highlights the results of a large study that "suggests that regular exercise [15 minutes a day, at least 3 times a week] is associated with a delay in onset of dementia and Alzheimer disease." Results showed that such exercise decreased the onset of dementia by 32%.6 This study joins a growing body of research that points to a connection between physical exercise and brain ﬁtness.
The Question: Are there medications that prevent or reverse normal cognitive decline and/or pathological dementia like Alzheimer's disease?
The Verdict: There are no "memory drugs" that are proven to allay normal age-related cognitive changes, nor is there a medication approved to prevent cognitive decline and dementia. Existing medication targeted at serious cognitive issues, such as Alzheimer's, are designed to minimize symptoms rather than prevent or cure the disease. Research is proceeding rapidly on this front, but it will likely take time to ﬁnd a "magic bullet" that can prevent the devastating effects of Alzheimer's and other forms of dementia.
The Evidence: Scientists are working to develop and test dozens of medications for Alzheimer's. Some of these are "vaccines," drugs that researchers hope can be administered in the early stages of Alzheimer's to prevent or reverse the brain changes that they believe cause the disease. Testing of one promising drug was suspended a few years ago due to a high incidence of serious side effects. Testing of other drugs continues, though—and some show promising results in animal models. Currently prescribed Alzheimer's drugs do not reverse the disease, however. The most commonly prescribed medications are cholinesterase inhibitors designed to treat early to midstage Alzheimer's patients. The purpose of these medications is to increase the level of a brain chemical called acetylcholine, which aids in memory and other cognitive skills. Drugs prescribed to treat moderate to severe stages of AD are designed to control the production of glutamate, a brain chemical that plays an integral role in information storage as well as learning and memory.
The Question: Will there ever be a "brain transplant" or prosthesis?
The Verdict: Currently, brain implants are somewhere between science ﬁction and reality. At some future point, brain prostheses might be able to replace damaged parts of the brain or help to regulate brain function.
The Evidence:Researchers at the University of Southern California are working on a computer chip to replace brain cells damaged by diseases like Alzheimer's. This chip is currently replacing part of a rat's hippocampus, and the scientists hope that one day, they will be able to implant a similar chip in humans who have brain damage.
Ultimately, as with physical ﬁtness, achieving brain ﬁtness will likely require that we combine a variety of strategies: physical exercise, brain exercise, a brain-healthy diet, and—when it comes to it—medical interventions. The good news is that science is making advances on all these fronts. Over the next few decades, we might just ﬁgure out how to keep our brains healthy for as long as our bodies can keep up.