Complain about a product or service

Fruit Juice May Reduce Alzheimer's Risk

August 31, 2006

• Low Levels of 'Good Cholesterol' Linked to Memory Loss, Dementia Risk • Chemical in Celery May Fight Alzheimer's • Dementia Linked To Obesity • Studies Find Link Between Diabetes and Alzheimer's • Lifestyle Linked to Alzheimer's Onset • Pot Belly in Middle Age Linked to Alzheimer's • 10 Million Boomers Face Alzheimer's • Alzheimer's Risk Higher in Victims' Children • Fast-Acting Alzheimer's Therapy Excites Researchers • Too Much Sugar May Increase Alzheimer’s Risk • Beta Carotene May Slow Memory Loss • Promising Alzheimer’s Discovery Reported • Misconceptions About Alzheimer's Vary Among Races • Mediterranean Diet May Extend Alzheimer’s Patients’ Lives • Researchers Link Smoking To Dementia • Caffeine May Keep Dementia At Bay In Women • Alzheimer’s Drug Seen As “Safe, Effective” • Researchers “A Step Closer” To Alzheimer’s Cure • FDA Approves Alzheimer’s Patch • Scientists Raise Hopes For Alzheimer's Vaccine • Researchers Hopeful About New Alzheimer’s Therapy • Blood Pressure Drugs May Provide Alzheimer’s Protection • Progress Toward Early Alzheimer's Diagnosis Reported • Alzheimer's Cases Up 10% In 5 Years • Loneliness Linked to Dementia • Gene Changes Identified in Alzheimer's • Mental Exercise May Help Seniors • Rote Learning Improves Memory in Seniors • Vegetables May Slow Memory Loss • Cabernet Sauvignon May Reduce Alzheimer's Risk • Fruit Juice May Reduce Alzheimer's Risk • Skin Test May Detect Alzheimer's Disease • Exercise May Prevent Dementia-Like Illnesses • An Apple A Day May Improve Memory • New Drug Reverses Alzheimer's Damage, Australian Researchers Report • Diabetes Drug May Help Treat Alzheimer's • For Women, Weight Loss May Precede Dementia • Researchers "Closer" To Preventing Alzheimer's • Statins Help Memory in Older Women • Study Links Healthy Diet To Reduced Alzheimer's Risk • Tea May Help Combat Alzheimer's • Education May Accelerate Alzheimer's Effects • Alzheimer's Found to be Mostly Genetic • Exercise May Reduce Risk of Dementia in Older People • Researchers Find DNA Link to Alzheimer's • Brain Scan, Fluid Analysis May Help Predict Alzheimer's • Eating Fish Associated With Slower Cognitive Decline • Word Recall An Alzheimer' s Tip-Off? • Interrupted Alzheimer's Trial Produced Promising Results • Gene Therapy May Offer Hope For Alzheimer's Patients • Alzheimer's Researchers Reverse Memory Loss in Mice • Alzheimer's Disease Reveals Itself Earlier, Study Finds

In a large epidemiological study, researchers found that people who drank three or more servings of fruit and vegetable juices per week had a 76 percent lower risk of developing Alzheimer's disease than those who drank juice less than once per week.

The study by Qi Dai, M.D., Ph.D., assistant professor of Medicine, and colleagues appears in the September issue of The American Journal of Medicine.

The researchers followed a subset of subjects from a large cross-cultural study of dementia, called the Ni-Hon-Sea Project, which investigated Alzheimer's disease and vascular dementia in older Japanese populations living in Japan, Hawaii and Seattle, Wash.

For the current study, called the Kame Project, the researchers identified 1,836 dementia-free subjects in the Seattle population and collected information on their dietary consumption of fruit and vegetable juices. They then assessed cognitive function every two years for up to 10 years.

After controlling for possible confounding factors like smoking, education, physical activity and fat intake, the researchers found that those who reported drinking juices three or more times per week were 76 percent less likely to develop signs of Alzheimer's disease than those who drank less than one serving per week.

The benefit appeared particularly enhanced in subjects who carry a genetic marker linked to late-onset Alzheimer's disease -- the most common form of the disease, which typically occurs after the age of 65.

The researchers chose to study this group because of the low incidence rate of Alzheimer's disease in the Japanese population. However, the incidence of Alzheimer's in Japanese people living in the United States is higher, approaching the incidence rates in Americans. This pointed to environmental factors like diet and lifestyle as important contributors to disease risk.

Originally, researchers suspected that high intakes of antioxidant vitamins might provide some protection against Alzheimer's disease, but recent clinical studies have not supported this hypothesis.

"We thought that the underlying component may not be vitamins, that there was maybe something else," Dai said.

Dai began to suspect that another class of antioxidant chemicals, known as polyphenols, could play a role. Polyphenols are non-vitamin antioxidants common in the diet and particularly abundant in teas, juices and wines.

Most polyphenols exist primarily in the skins and peels of fruits and vegetables. Recent studies have shown that polyphenols (like resveratrol in wine) extend maximum lifespan by 59 percent and delay age-dependent decay of cognitive performance in animal models.

"Also, animal studies and cell culture studies confirmed that some polyphenols from juices showed a stronger neuroprotective effect than antioxidant vitamins. So we are now looking at polyphenols," Dai said.

The next step, said Dai, is to test the subjects' blood samples to see if elevated levels of polyphenols are related to the reduced risk of cognitive decline and Alzheimer's disease. This would provide further evidence of the role of juice polyphenols in Alzheimer's disease risk. It also may point to the types of juice that would be most beneficial.

"We don't know if it is a specific type of juice (that reduces risk). That information was not collected in the current study," said Dai. "But we can use plasma to narrow down the kinds of juices."

However promising the study results appear, Dai cautioned, it's important that the general public not jump the gun regarding the value of juice as a preventive measure for Alzheimer's disease.

"A few years ago, hormone replacement therapy, NSAIDs (nonsteroidal anti-inflammatory drugs) and antioxidant vitamins showed promise (in preventing or slowing Alzheimer's disease), but recent clinical trials indicate that they do not," Dai said. "More study, I think, is needed."

Report Your Experience
If you've had a bad experience -- or a good one -- with a consumer product or service, we'd like to hear about it. All complaints are reviewed by class action attorneys and are considered for publication on our site. Knowledge is power! Help spread the word. File your consumer report now.