National Alzheimers Disease Institute


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Alzheimer’s Disease

Risks and Prevention Options

P. Anthony Chapdelaine, Jr., MD, MSPH, Exec. Dir./Sec.*

Alzheimer’s Disease: the problem

You already know that Alzheimer’s Disease is the most common form of the various dementias. President Ronald Regan and singer-songwriter Glen Campbell are two names of people who were diagnosed with Alzheimer’s Disease (AD) with whom you would be familiar. Unfortunately, there are many more. One estimate puts the number of people in the US with AD at 4.5 million, and the numbers are expected to triple over the next three decades.1

You already know that AD is a neurodegenerative disorder. In other words, certain cells in the brain slowly decay which causes progressive memory loss that is much more severe and advanced than is typical for an aging brain. Thinking, remembering, reasoning – the traits which we most cherish as forming our personal identities – gradually leave us.1,2,3  This eventually causes us to feel depressed, confused, lost, and angry when we can’t understand what is happening to us. Soon, we are unable even to care for ourselves. 1,2,3

You may not know what the brain of someone who had AD looks like. In small areas there are “neurofibrillary tangles” inside the brain cells, and “plaque formation” (amyloid-beta protein) found outside of these same brain cells.1  How these form and what to do about them are still largely a mystery to scientists, who are continuing to conduct research.

Alzheimer’s Disease Risk Factors

What you should know is that scientists have identified several “risk factors – some which you can change and others which you cannot change:1,3  

Most AD occurs after age 65, and between 65 and 74 years-of-age nearly 5% of people are diagnosed with AD. This percentage jumps to 50% after age 85!

Family history and genetics play a definite, but very small role, in the risk of having AD. Even families with a genetic predisposition in which AD occurs before age 65 (early-onset AD) account for only one-out-of-a-thousand cases of AD. The APO-E4 gene is one of three genes that appear to predispose to AD; however, it is not clear whether these genes have much impact on causing AD. Something else seems to be happening besides genetics.1

AD and another dementia, vascular dementia, appear to share a connection with common cardiovascular problems: as the arteries in and around the heart clog, so do arteries elsewhere in the body, including the brain. Thus high blood pressure, diabetes, and high oxidized LDL and other factors (lipoprotein A, homocysteine, etc.) contribute to the clogging of arteries and can lead to heart disease, strokes, and dementia.

The other risk factors that contribute to AD risk are those you can control, such as: dietary choices, lifestyles (stress, sleep, activities challenging the brain), routine exercise, social community-networks, minimizing alcohol, avoiding tobacco.

Alzheimer’s Disease Mechanisms (How Does Brain Change?)

As to how all these modifiable and non-changeable risk factors cause AD? There is no answer yet. There are four major theories being studied.1  The evidence suggests that most AD develops over decades. During this time, the symptoms of memory loss and thinking problems do not show up. When enough brain cells die around the hippocampus (the part of the brain that helps form memories) there may be a symptom such as a problem with word-finding. Eventually brain cell destruction spreads, which shows up as an obvious problem known as AD.

Alzheimer’s Disease Treatment – But No Cure

There is currently no drug that will cure Alzheimer’s Disease, or even slow its course significantly, and certainly no drug that can prevent it yet. Don’t let somebody tell you such drugs exist. As the NIH states:

“Alzheimer’s disease is complex, and it is unlikely that any one drug or other intervention can successfully treat it. Current approaches focus on helping people maintain mental function, manage behavioral symptoms, and slow or delay the symptoms of disease. Researchers hope to develop therapies targeting specific genetic, molecular, and cellular mechanisms so that the actual underlying cause of the disease can be stopped or prevented.”3

We mentioned that most research is conducted by universities or drug companies (very often through universities). For this reason there tends to be a bias away from natural substances such as vitamins (which make no money) and toward drugs (which make a lot of money). Most researchers think they understand vitamins and herbs, but actually know very little about these substances’ clinical and practical applications, and even less about the studies conducted outside the US that typically show nutrients and vitamins in a favorable light.

Another problem with the studies the NIH relies on in providing guidance at its website is that these are not always true studies. They are “meta-analyses,” which are statistical studies of the results of actual studies. Unfortunately, the meta-analyses themselves depend on which studies the researchers select and this itself can introduce bias and false results in the meta-analysis.

Like any analysis, the end result of a meta-analysis depends: it depends on the particular studies chosen among all studies, which then are included in the analysis; it depends on the biases of the researchers in choosing the studies, that is, the criteria used to select which studies are included, and which excluded; it depends on whether the studies chosen for the statistical analyses were conducted by knowledgeable researchers (which is more often not the case when herbs, vitamins, and other nutrients are involved) since most academic researchers end up using an insufficient dose or attempt to study – just like they do for drugs – one small component (like a single vitamin) at a time, not understanding that the doctors and practitioners world-wide who obtain good clinical results using the very same vitamins and nutrients are also using additional vitamins and herbs to enhance the effects, as well as ensuring that their patients are exercising, eating vegetables and fruit, not smoking and so on. Unfortunately, the studies included in the meta-analyses do not do that.

The result is what the computer scientists learned long ago: GIGO – garbage in, garbage out.

See additional articles on this website that examine recent research indicating how lifestyle, diet, environmental conditions, and particular vitamins and nutrients help us maintain our brain health and function.

* The National Alzheimer’s Disease Institute is a project of The National Fund for Alternative Medicine



  1. Singh SK, Srivastav S, et al, “Overview of Alzheimer’s Disease and Some Therapeutic Approaches Targeting Aβ by Using Several Synthetic and Herbal Compounds,” Oxidative Medicine and Cellular Longevity, 2016, 2016, doi:10.1155/2016/7361613.