Healthy Aging and Prevention
Does Exercise Protect the Brain?
We know that exercise and physical activity is important to preventing heart disease, lowering cholesterol and managing diabetes. But what about protecting the brain from Alzheimer’? Observational and intervention studies have suggested that physical exercise may be a factor in decreasing the risk for Alzheimer’s disease and normal memory loss due to aging.
Research with animals helps us to understand how exercise protects the brain. Studies with older rates and mice show that exercise increases the number of small blood vessels that supply blood to the brain, the number of connections between nerve cells and raises the level of an important brain protein that is important to memory and learning.
Research with humans has also demonstrated that physical activity increases the number of connections between brains cells as well as maintains the old connections. These new connections are vital to healthy cognition which includes awareness, perception, reasoning, and judgment. In a year-long study, 65 older people were divided into two groups; the first group exercised daily doing an aerobic program of walking for 40 minutes while the second group did a nonaerobic program of stretching and toning exercises. After the study finished, the aerobic walking group showed improved connectivity in the part of the brain that impacts daydreaming, envisioning the future, and recalling the past. This group also improved on planning, organizing, strategizing, paying attention to and remembering details.
More research trials are ongoing to help determine the impact to f exercise on fighting off Alzheimer’s.
Does what I eat affect my brain’s health?
We all know that a diet high in fruits, vegetables, whole grains and low in fat and added sugar can reduce the risk of heart disease, type 2 diabetes and lowers cholesterol. So what about the impact on memory? Researchers are examining whether a healthy diet also can help preserve memory or reduce the risk of Alzheimer’s.
A number of studies found, that a diet rich in vegetables, especially green leafy vegetables and cruciferous vegetables like broccoli is associated with a reduced rate of decline in reasoning and understanding. One epidemiological study reported that people who ate a “Mediterranean diet” decreased their risk of developing mild cognitive impairment by 28% and a decreased their risk of progressing from MCI to Alzheimer’s disease by 48%. The main aspects of this diet include proportionally high consumption of olive oil, legumes, unrefined cereals, fruits, and vegetables, moderate to high consumption of fish, moderate consumption of dairy products (mostly as cheese and yogurt), moderate wine consumption, and low consumption of meat.
Studies have found that food high in saturated fats and refined carbohydrates (white sugar, for example) could hurt memory function. In one study, scientists fed rats food that was high in fats and simple carbohydrates for 3 months. The rats fed the high fat “Western Diet” performed significantly worse on certain memory tests than rats fed a diet containing one-third the fat.
Diet studies have also examined DHA (docosahexaenoic acid), an omega-3 fatty acid found in salmon and a few other fish. These studies looked at mice that were bred to have beta-amyloid proteins which are the key feature of Alzheimer’s. The studies found that DHA reduces beta-amyloid plaques, abnormal protein deposits in the brain that are a hallmark of Alzheimer’s. Even though clinical trial studying DHA in humans showed no impact on people with mild to moderate Alzheimer’s disease, it is possible that DHA supplements could be effective if started much earlier before memory symptoms appear.
Will controlling my diabetes and high cholesterol protect against Alzheimer’s?
Conditions and diseases such as vascular disease, high blood pressure, heart disease, and type 2 diabetes may increase the risk of Alzheimer’s and cognitive decline. Observational studies have been the primary source of information about the links between these conditions and Alzheimer’s. Past studies revealed that high cholesterol and obesity during midlife, the risk factors for heart disease, have also been linked to increased risk of Alzheimer’s disease. High blood pressure and diabetes are additional conditions that have been linked to Alzheimer’s. Studies have shown that abnormal insulin production (insulin is the hormone involved in diabetes) contributes to Alzheimer’s-related brain changes.
Many studies are looking at whether preventing or controlling these diseases and conditions through medication, diet and exercise can reduce the risk for Alzheimer’s. These results so are mixed. One large NIH-funded clinical trial compared intensive blood sugar lowering medicines with standard treatment in nearly 3,000 older adults with diabetes. After 3 years there was no significant difference in memory function between the two groups. Another clinical trial is testing insulin nasal spray this in older adults with MCI or mild to moderate Alzheimer’s disease to see if it can improve memory and daily functioning.
Additional studies and clinical trials are looking at aspirin, medications used to treat high blood pressure and other heart conditions, and the diabetes drugs metformin and pioglitazone. One NIH clinical trial is looking at how lowering blood pressure to or below current recommended levels may affect cognitive decline and the development of MCI and Alzheimer’s disease.
Will Keeping Your Brain Active make a difference in preserving my memory?
Observational studies have linked social engagement through work, volunteering, or living with someone and mentally stimulating activities such as reading, going to lectures, and playing games with lowering the risk of Alzheimer’s disease.
One large study of healthy older people found a relationship between more frequent social activity and better thinking, understanding, learning, and remembering. It is not clear whether improved cognition resulted from the social interaction itself or from related factors, such as increased intellectual stimulation, that generally accompany social interaction. Another large observational study looked at the impact of ordinary activities like listening to the radio, reading newspapers, playing puzzle games, and visiting museums. After 4 years, the risk of developing Alzheimer’s disease was 47 percent lower, on average, for those who did the activities most often than for those who did them least frequently.
Formal memory training also seems to have cognitive benefits. In the Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) trial, for example, healthy adults 65 and older participated in 10 sessions of memory training, reasoning training, or processing-speed training. The sessions improved participants’ mental skills in the area in which they were trained. These improvements persisted 10 years after the training was complete.
Additional studies are examining the combination of formal cognitive training and exercise while other studies are examining different types of formal cognitive training like learning digital photography or quilting and volunteering at local schools
The reasons for the apparent link between social engagement or intellectual stimulation and Alzheimer’s risk aren’t entirely clear, but scientists theorize that these activities may protect the brain by establishing “cognitive reserve,” which allows the brain to operate effectively even when it is damaged or some brain function is disrupted. These activities may help the brain become more adaptable in some mental functions, so it can compensate for declines in other functions. Scientists also suggest that people who engage in these activities may have other lifestyle factors that protect them against Alzheimer’s disease. One theory is that less engagement with other people or in intellectually stimulating activities could be the result of very early effects of Alzheimer’s rather than its cause.
Information courtesy of the National Institutes on Aging
So what is Normal memory loss?
Forgetfulness can be a normal part of aging; however, aging does not result in an inevitable loss of cognitive abilities. As people age, both the body and the brain change. Often it takes longer to perform a task, learn new things and it is more difficult to multi task. Scientists have found that given enough time, older adults do as well on complex memory or learning tests as younger people, In fact, as they age, healthy adults usually improve in areas of mental ability such as vocabulary. While certain areas of thinking do show a normal decline as we age, others remain stable.
Below is a description of how aspects of cognitive function change with age.
- Intelligence: “Crystalized” intelligence, i.e., knowledge or experience accumulated over time, actually remains stable with age. On the other hand, “fluid” intelligence or abilities not based on experience or education tend to decline. Examples of “fluid” intelligence include ability to think and react quickly, mental flexibility or mental “mulit-tasking”, and learning of new information.
- Memory: Remote memory or recall of past events that have been stored over many years remains relatively preserved in old age. Recent memory or the formation of new memories, however, is more vulnerable to aging. Most often, this means that older individuals take longer (i.e., have to hear/see it more times) to learn new information than they may have when they were younger.
- Attention: Simple or focused attention such as the ability to attend to a television program tends to be preserved in older age. Difficulties may be encountered, however, when divided attention is required such as trying to pay attention to the television and simultaneously talk on the telephone.
- Language: Verbal abilities including vocabulary are preserved as we age. Common changes have to do with word retrieval or the process of getting words out. It takes longer and is more difficult to find the words one wants when engaged in conversation or trying to recall names of people and objects. The information is not lost but it is more difficult to retrieve.
- Reasoning and Problem Solving: Traditional ways of approaching solutions are maintained in older persons. Wisdom of experience in older age can lead to better approaches to some of life’s problems than some younger individuals. However, problems that have not been encountered during the older individual’s life may take extra time to figure out, and it may be difficult to think of alternative ways of solving a problem.
- Speed of Processing: Aging does affect the speed with which cognitive and motor processes are performed. This does not mean that the activities cannot be performed, but rather that they take longer!
What else can cause memory loss as we age?
Some memory problems are related to treatable conditions--medication side effects, vitamin B12 deficiency, chronic alcoholism, tumors or infections in the brain, or blood clots in the brain. Some thyroid, kidney, or liver disorders also can lead to memory loss.
Emotional problems, such as stress, anxiety, or depression, can make a person more forgetful and can be mistaken for dementia. Dealing with major life changes such as death or retirements leaves some people confused or forgetful.
Information courtesy of the National Institutes on Aging
What does Mild Cognitive Impairment mean?
Mild Cognitive Impairment (MCI) is a condition that means there is clear evidence of cognitive problems, most often involving learning and remembering new information. However individuals can still perform normal day to day activities such as managing household, medication, and financial matters. Most people with MCI recognize their memory is not as good as it was at one time. People with this condition have more memory problems than normal for people their age, but their symptoms are not as severe as those of Alzheimer's disease As a result, they often express concern they may develop a dementia such as Alzheimer’s Disease (AD) and want to take steps to preserve their memory.
The diagnosis of “mild cognitive impairment” means that an individual meets the following criteria:
- Short term memory problems and/or problems involving other cognitive (thinking) areas such as language and reasoning
- More cognitive difficulty than others of the same age and education
- Normal function in all other areas of daily living (e.g. paying bills, managing medications)