Can Supplements Reduce Your Risk of Alzheimer’s Disease?
Although the cause of Alzheimer’s disease is unknown, doctors can treat patients in the early to middle stages of the disease. For example, we know that certain brain cells manufacture acetylcholine. We also know that as we age, these cells begin to die off.
Fortunately, the FDA has approved a group of medications called “acetylcholinesterase inhibitors.” These medications increase the amount of acetylcholine in the brain by decreasing its natural breakdown and consequently help alleviate confusion and language difficulty. They may also help control behavioral symptoms, such as
As a result (and playing on the fears of many older Americans) many companies are promoting the use of certain supplements to prevent and treat memory problems. Scientists are actively investigating the effects of these supplements, but for the most part, there is little to no evidence to support their claims. There is
Supplements Believed to Stop or Slow the Progression of Alzheimer’s Disease
There are several different types of supplements thought to improve mental function and reduce the risk of Alzheimer’s disease.
An excess of free radicals (also known as oxidants) may contribute to the development of Alzheimer’s disease. Antioxidants may protect against Alzheimer’s disease by limiting the buildup of toxic amyloid protein. So far, the evidence suggests that diets rich in foods containing antioxidant vitamins, such as
Evidence is also mixed for
Other Essential Nutrients
There are a number of other essential nutrients that are also purported to improve cognitive function. These include:
Carnitine, a derivative of the amino acid
Phosphatidyl serine and choline are both involved in the structure and maintenance of cell membranes. Phosphatidyl serine has been shown to be mildly effective in the early stages of Alzheimer’s disease. Clinical trials of choline have not.
Because of its antioxidant properties, coenzyme Q10, which is involved in energy production, may play a role in reducing AD risk. However, research in this area is preliminary. There are no published clinical trials of coenzyme Q10 in Alzheimer’s disease.
It has been suggested that a dietary deficiency of omega-3 and omega-6 (essential) fatty acids could be a risk factor for Alzheimer's disease. Again, research in this area is preliminary.
Are Supplements Safe?
Buyers should beware that products that are natural are not necessarily safe or good for you. If you do choose to take supplements, use the following chart as a guide. Remember that a healthy diet will provide you with adequate vitamins and minerals.
Recommended Adult Dose
|Vitamin E||22 IU/d (15 mg/d); 1,500 IU (1,000 mg) per day is the Tolerable Upper Intake Level (UL)*|
|Vitamin C||90 mg/d for men, 75 mg/d for women; the UL is 2,000 mg/d *|
|Beta-carotene||None (Supplements are not advisable at any level)*|
|Gingko||40 to 80 mg 3 times daily**|
|Huperzine A||100 to 200 micrograms (µg) twice a day**|
|Vinpocetine||10 mg 3 times per day**|
Other essential nutrients
|Carnitine||500 to 1,000 mg 3 times daily**|
|Phosphatidyl serine||Up to 100 mg two or three times a day**|
|Choline||The Adequate Intake (AI) level is 550 mg/d for men and 425 mg/d for women; the UL is 3.5 g/d*|
|Coenzyme Q10||30 to 300 mg/d**|
|Omega-3 fatty acids||The AI is 1.6 g/d for men and 1.1 g/d for women*|
|Omega-6 fatty acids||The AI is 17 g/d for men and 12 g/d for women*|
|Folate (folic acid)||400 µg/d; the UL is 1,000 µg/d*|
|Vitamin B12||2.4 µg/d; no UL as been set*|
*Set by the Institute of Medicine
**Suggested intake levels only—based on “typical” dosages used in studies
Are Supplements Worth it?
Clearly, the market for memory enhancers is huge. And, as the population ages, interest in ways to slow or stop the progression of Alzheimer’s disease will only continue to grow. Unfortunately, since further research is needed, it may be years before the benefits and risks of supplements are fully established. Moreover, supplements are expensive. Some brands could cost you $100 a month or more.
Furthermore, patients and families of AD patients should talk with their doctors before taking any supplements or over-the-counter medications.
In the meantime, consider that by exercising, eating right, and using your mind—reading books, playing games, learning a new language—you will greatly improve your chances of preserving mental acuity. It may not be as simple as popping a pill, but the gains are worth it.
Alzheimer’s Disease Education and Referral Center
National Alzheimer’s Association
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Last reviewed January 2009 by
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