Although much progress has been made over the past decade, there is still much more to be understood about the brain’s inner workings, specifically on how to prevent or reverse cognitive decline.
The CDC defines dementia as a general term used to describe the impaired ability to remember, think, or make decisions in a way that interferes with everyday activities.1 An estimated 5 million individuals in the United States have dementia with Alzheimer’s disease (AD), the most common form.1 Interest in brain health is high, with recent survey results showing that about 25% of adults over age 50 years take a supplement to improve their brain health with the promise of enhanced memory and sharper attention and focus.2
Age has long been known as the strongest predictor of developing dementia, but there are other risk factors. An individual with a family history is more likely to develop dementia. Black individuals are twice as likely, and Hispanic individuals are 1.5 times more likely to have dementia compared with White individuals.1 Hypertension in midlife may increase the risk of cognitive decline in older age, because it damages blood vessels, which leads to vascular dementia.3 Other conditions, such as diabetes and traumatic brain injury, have links to dementia as well.
TREATMENT OF DEMENTIA
Dementia treatment includes addressing the underlying cause, whether that is a chronic disease, medication, or other factors. AD has no cure, but some medications can slow the process and treat symptoms of anxiety or behavioral changes. Although there are still many unanswered questions about dementia, there are proven strategies that can be adopted throughout life to slow cognitive decline in older age.
LIFESTYLE MODIFICATIONS
Exercise
The research results have demonstrated the link between brain health and exercise, and several studies have looked at the effect on cognitive decline in older age. The results of a study of more than 30,000 participants found that those who were physically fit throughout the 10-year study were almost 50% less likely to develop dementia in older age than the least fit study participants.4 The study results also showed that participants who were out of shape in middle age who became fitter throughout the study showed the same substantial risk reduction for dementia as their counterparts who were fit at the outset of the study.4 This shows that it is never too late to start exercising to receive cognitive benefits. Other studies have looked at the intensity and length of exercise, and results found that regular moderate- to high-intensity exercise and weight resistance training are most beneficial.4,5
Nutrition
Changes in the brain can happen years before symptoms appear, and nutrition has been studied as a possible way to slow the aging process, specifically through the Mediterranean and Mediterranean-DASH Intervention for Neurodegenerative Delay diets. The Mediterranean diet emphasizes fish, fruits, grains, legumes, vegetables, and whole grains. Not only does good nutrition help with chronic disease risk factors, such as cardiovascular disease and diabetes, but it also may protect the brain through anti-inflammatory and antioxidant processes. So far, there is no hard evidence that avoiding or eating certain foods lowers the risk of AD, but eating fish and green, leafy vegetables and following a low-salt and -sugar diet may reduce the risk of developing dementia.
Sleep
Although investigators are still debating whether dementia leads to poor sleep or poor sleep exacerbates dementia, they agree that there is a link. The National Institutes of Health reported in 2018 that sleep deficits might increase the β-amyloid proteins in the brain that are linked to AD.6 The results of another study that followed individuals older than 25 years showed a 30% increased dementia risk in 50-, 60-, and 70-year-olds who slept 6 or fewer hours a night.7
Supplements
Most supplements are not tested in clinical, controlled, randomized trials, and the FDA does not regulate supplements. Because of this, their efficacy and safety are largely unknown, as is how supplements interact with other medications. There are several supplements that individuals regularly use that have shown small benefits in the results of some studies.
The most common of these are omega-3 and vitamins E and B6, B9 (folate), and B12. Omega-3s are found in fatty fish, such as mackerel and salmon, and nuts, seeds, and vegetable oils, which have all shown anti-inflammatory and antioxidant effects on the brain. The results of a 2014 study showed that vitamin E might help individuals with AD continue to perform daily functions. However, vitamin E does not prevent AD or reduce other symptoms.8 Vitamin E is thought to contribute to brain health by reducing oxidative stress. The vitamins B6, B9 (folate), and B12 help break down homocysteine, which has been shown to contribute to AD and dementia. Most people get enough vitamin B in their diets, but if they don’t, the deficit is reversible through supplementation, which is rarely needed long term.
There is also an herb specifically indicated for memory, Gingko Biloba, but research does not conclusively back the claim. One of the largest studies trying to connect it to memory was the Ginkgo Evaluation of Memory Study. With 3000 participants taking a supplement over 6 years, the results did not show that Gingko Biloba lowered the risk of developing overall dementia.9
CONCLUSION
Lifestyle choices, such as diet and exercise, may help prevent AD and support brain health, as well as lower the risk of other diseases, such as diabetes and heart disease, which have been linked to AD. Healthy lifestyle choices can improve health and possibly protect the brain