Alzheimer's Disease

Alzheimer's disease (AD) is a progressive, degenerative brain disease that results in impaired memory, thinking, and behavior. It is the most common cause of dementia in the elderly and affects at least three to four million people in the United States. People with AD experience gradual memory loss as well as impaired judgement, difficulty concentrating, loss of language skills, personality changes, and a decline in the ability to learn new tasks. Memory loss usually begins at about age 65 and symptoms tend to become severe within 8 to 10 years. In some cases, symptoms may appear earlier in life and advance at a faster or slower rate, but most people who develop symptoms before the age of 60 tend to have more severe forms of the disease. Currently, there is no cure for AD, but studies suggest that medications, herbs and supplements, and lifestyle adjustments may all help to slow the progression and improve the symptoms of the disease.

Signs and Symptoms

The early symptoms of AD are occasionally overlooked because they resemble signs that many people attribute to "natural aging." The following are the most common signs and symptoms of AD.

Psychological Symptoms Physical Symptoms


The causes of AD are not entirely known but are thought to include genetics and environmental factors. New research indicates that free radicals (highly reactive molecules that can cause oxidation, or damage to cells) may play a role in the development of AD.

A gene for the protein epsilon apolipoprotein (Apo E)—especially Apo E3 and Apo E4 varieties—is thought to accelerate the formation of abnormal deposits (called plaques) in the brain and increase the risk for AD. Reports indicate that between 50% and 90% of those with the Apo E4 gene develop AD. However, even people without inherited genes for the disease can get AD.

Scientists also believe the environment may play a part in AD because people in different regions of the world have widely varying risks of developing the disease. For example, people living in Japan and West Africa have much less risk for AD than Japanese and Africans living in the United States.

People with AD have abnormal deposits, or plaques, in their brain tissue. These plaques contain beta amyloid, a protein that releases free radicals, or highly reactive molecules that can cause damage to cells through a process called oxidation. These free radicals are believed to lower levels of acetylcholine (a brain chemical that helps transmit impulses in the nervous system) and damage brain tissue, bringing on the symptoms of AD.

Although not confirmed by scientific studies, other factors that have been speculated to contribute to the development of AD include infections (such as herpesvirus type 1), exposure to metal ions (such as aluminum, mercury, zinc, copper, and iron), or prolonged exposure to electromagnetic fields.

Risk Factors

The causes and risk factors contributing to the development of AD are not entirely clear. The following all appear to have an association with AD to varying degrees.


There is no definitive test for AD, and a true diagnosis of AD can only be made after a person dies and an autopsy is performed on the brain. All individuals with AD have an accumulation of abnormal deposits (called plaque) and tangled nerve cells in their brains. The physician will try to narrow down a diagnosis, however, by eliminating the possibility of other illnesses. He or she will ask the individual (or a close family member) to describe the primary symptoms, and how long they have been noticeable.

The following tests may also be used to aid in the diagnosis.

Preventive Care

Treatment Approach

Unfortunately, there is no cure for AD. The goal in treating AD is to slow the progression of the disease and improve symptoms. The most promising treatments for AD include medications that increase the amount of acetylcholine in the brain (such as donepezil), antioxidants that scavenge free radicals (such as vitamin E and ginkgo biloba), lifestyle modifications (such as walking programs and relaxation training) to reduce anxiety and improve behavior. Studies suggest that music therapy, the use of music to relax patients and bolster the immune system, may be healing for those with AD as well. It is also important that family members of people with AD get emotional support and assistance with the demanding tasks of caregiving.


Research indicates that the following lifestyle modifications may help improve behavior in people with AD. Individuals with AD may also have particular dietary concerns. They may require:


The following medications increase the amount of acetylcholine, in the nervous system and slow the progression of AD: The following medications may ease the symptoms related to AD:

Nutrition and Dietary Supplements

Damage caused by free radicals is thought to play a major role in the development of AD. Many researchers have investigated whether antioxidants (agents known to scavenge free radicals) may ease the symptoms of dementia, increase the life span of those with AD, and help prevent the disease. Two antioxidants in particular, vitamins E and C, have shown promise in both the prevention and treatment of the disease. Research on other supplements is less convincing.

Vitamin E and Vitamin C
Vitamin E dissolves in fat, readily enters the brain, and helps slow down the cell damage that occurs naturally with age. In a well-designed study involving 341 people with AD who were followed for 2 years, researchers found that people who took vitamin E supplements had improvement in their symptoms and increased survival rates compared to those who took placebo.

Two large trials suggest that vitamins E and C may prevent the onset of AD, improve cognitive skills in healthy individuals, and decrease the symptoms of dementia. In one of the studies, more than 600 healthy individuals were followed for an average of 4 years. A total of 91 people developed AD, but none of the participants who took vitamin E or C supplements developed the disease.

S-adenosylmethionine (SAMe)
SAMe is a naturally occurring compound that increases the body's levels of serotonin, melatonin, and dopamine. Clinical studies suggest that people with AD and depression have depleted levels of SAMe in their brain tissue. While it has been reported that some people with AD have improved cognitive function from SAMe supplementation, further studies are needed to determine how safe and effective this supplement may be for individuals with the disease.

Beta-carotene and Vitamin A
Preliminary studies suggest that levels of vitamin A and its precursor, beta-carotene, may be significantly lower in people with AD compared to healthy individuals, but the effects of supplementation have not been studied.

Vitamin B9 (Folate) and Vitamin B12
Folate is a substance critical to the health of the nervous system and to a process that clears homocysteine from the blood. Homocysteine is a body chemical that contributes to chronic illness such as heart disease, depression, and AD. Elevated levels of homocysteine and decreased levels of both folate and vitamin B12 have been found in people with AD, but again, the benefits of supplementation for dementia are unknown.

In addition to being structurally similar to the brain chemical acetylcholine, acetyl-L-carnitine is a scavenger of free radicals and is involved in the growth of brain cells. Several studies have examined the role of acetyl-L-carnitine in treating AD, but results have been conflicting. For example, one trial suggests that this supplement may help prevent the progression of AD in the early stages of the disease, but it may worsen symptoms in later stages of the disease. Use of this supplement for AD should be avoided, therefore, until more information is available. Reported side effects include increased appetite, body odor, and rashes.

Phosphatidylserine (PS)
PS is a naturally occurring substance found in the body that promotes cell health and boosts the activity of acetylcholine and other brain chemicals. Animal and laboratory studies suggest that this supplement may protect the brain from damage. Clinical trials have found that it may improve memory, ease symptoms in those with mild to moderate dementia, and prevent cognitive decline in middle-aged individuals.

Red Wine and Grape Juice
Resveratrol, a flavonoid or plant substance found in red wine and grape juice, is an antioxidant that may benefit people with AD. Because the alcohol in red wine may contribute to falls, interactions with medications, and sleepiness, it is not recommended for those with the condition.


Ginkgo (Ginkgo biloba)

Ginkgo is widely used in Europe for treating dementia. It improves blood flow in the brain and contains flavonoids (plant substances) that act as antioxidants. Although many of the clinical trials have been scientifically flawed, the evidence that ginkgo may improve thinking, learning, and memory in people with AD has been highly promising.

Clinical studies indicate that gingko provides the following benefits for people with AD: Recommended dosages for ginkgo range between 120 to 240 mg per day. Reported side effects have been minor, but ginkgo should not be taken with blood-thinning medications (such as warfarin), vitamin E, or a class of antidepressants called monoamine oxidase inhibitors (MAOIs).

Preliminary studies indicate that the following herbs may also slow the progression of AD and improve memory and behavior: Although the following herbs have not been investigated in clinical studies, a professional herbalist may recommend the following for people with AD:

Other Considerations

Prognosis and Complications
A person with AD can experience the following complications: There is no known cure for AD; the disease naturally progresses and worsens over time. People with the disease can survive for many years, however. While most people with AD die within 8 to 10 years, some live as long as 25 years. Some people decline steadily during their disease, while others reach major plateaus where their symptoms advance quite slowly. Men and people with a long-standing history of high blood pressure are more likely to decline rapidly. Additionally, the older a person with AD becomes, the more likely he or she is to decline rapidly. An accurate, early diagnosis gives affected individuals a greater chance of benefiting from existing treatments.


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