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Alzheimer's disease and diet

Consuming a diet rich in vitamins E and C as well as fish can greatly reduce one's risk of developing Alzheimer's disease. Further help in preventing the disease may come from limiting the amount of total fat, saturated fat and cholesterol in one's diet.

Alzheimer's disease
A progressive condition, Alzheimer's disease damages areas of the brain involved in memory, intelligence, judgment, language and behavior. It is the most common form of mental decline in older adults and is usually diagnosed at age 70 or older. The disease affects not only memory, but behavior, personality, ability to think and the ability to function from day to day in four million Americans.

Although its cause is still unknown, most experts believe multiple factors are involved. A family history of the disease can greatly increase one's risk of developing Alzheimer's, as well as smoking cigarettes, serious head injuries, elevated homocysteine levels and exposure to elevated levels of lead and/or zinc.

At present, there is no cure for Alzheimer's disease. Drug treatments are primarily used to treat symptoms rather than prevent mental deterioration. However, scientists believe diet may play an important role in preventing this debilitating disease.

Antioxidants
Research has shown that consuming a diet rich in certain vitamins, called antioxidants, may help decrease one's risk of developing Alzheimer's disease. Of these antioxidant vitamins, vitamin E and vitamin C have proved to be most influential.

Antioxidants help eliminate harmful free radicals from your body, helping to prevent a variety of diseases such as cancer. Antioxidants may also improve immune function as well as lowering one's risk for infection.

Vitamin E is a fat soluble vitamin found primarily in vegetable and nut oils, as well as in spinach and whole grain products. Vitamin C is a water soluble vitamin most commonly found in citrus fruits, such as oranges and grapefruit, as well as in tomatoes, spinach and red peppers. For maximum prevention, it is recommended that these vitamins be provided by actual foods in the diet rather than nutritional supplements.

Fat/cholesterol
Consuming a diet lower in cholesterol is also thought to be beneficial in Alzheimer's prevention. Cholesterol comes from animal products, such as eggs, meat, poultry, fish and dairy products. The American Heart Association recommends consuming no more than 300 mg of cholesterol per day for good health.

If blood cholesterol is too high, it can build up in blood vessels, increasing risk for heart attack or stroke. Elevated blood cholesterol may be related to the development of Alzheimer's disease because high fat diets are thought to impair learning and memory performance. High levels of cholesterol in the blood or a diet high in saturated fat can triple a person's risk for developing this disease.

Conversely, consuming a diet lower in total fat as well as saturated fats may be beneficial in preventing cardiovascular or Alzheimer's disease. Foods high in fat and saturated fat include:

• animal products (meat and dairy)
• butter and cooking oils
• fried foods

Omega-3 fatty acids
Omega-3 fatty acids, found almost exclusively in fish, can greatly decrease one's risk of developing Alzheimer's disease. Fish containing high amounts of omega-3 fatty acids include:

• mackerel
• lake trout
• herring
• sardines
• albacore tuna
• salmon

Omega-3 fatty acids have anti-inflammatory properties that can significantly increase a person's performance in learning and memory tasks. Scientists have shown that consuming just one fish meal per week can lead to a 60 percent reduction in the risk of developing Alzheimer's disease compared to diets in which fish are not consumed. [Moderation is key. See also: Mercury rising, Nutrition Advisor, March 2004.]

The bottom line
In addition to reducing risk for developing Alzheimer's disease by following the "brain healthy" suggestions above, a diet high in vitamins E and C and low in fats and cholesterol can also decrease risk of developing cardiovascular disease or of having a heart attack or stroke.

The Yale-New Haven Nutrition Advisor is created by registered dietitians and dietetic interns who staff the Nutrition Clinic at Yale-New Haven Hospital. For information, contact the Nutrition InfoLine at (203) 688-2422.

For more information on this topic, you could visit:

• Alzheimer's Association
• Alzheimer's disease, American Health Assistance Foundation

Other issues addressed by Yale-New Haven Nutrition Advisor:

• Does fast food have to equal fat food?
• The truth about trans fats
• Understanding yogurt
• Thinking about going low-carb?
• What's to drink?
• Obesity—it's not just for grown-ups anymore
• Fruits and vegetables: Always in season
• Calcium: Not just for bones anymore!
• Mercury Rising
• A powerful B vitamin: Folate
• Vegging out
• Manic for organic
• Beta carotene
• Archive

Last revised: March 10, 2005 (jj)

Home page URL: http://www.ynhh.org

All information is intended for your general knowledge and is not a substitute for medical advice or treatment for specific medical conditions. You should seek prompt medical care for any specific health issues and consult your physician before starting a new fitness regimen.