Flavonols: Reducing Risk of Alzheimer's

"Eating more fruits and vegetables and drinking more tea could be a fairly inexpensive and easy way for people to help stave off Alzheimer's."
With the elderly population increasing worldwide, any decrease in the number of people with this devastating disease, or even delaying it for a few years, could have an enormous benefit on public health."
"This study is a piece of the puzzle for anybody wanting to think about benefits for Alzheimer dementia or disease. We need to think about it as a lifestyle modification."
Dr.Thomas Holland, researcher, Rush University, Chicago

Microcosm diagram of the mind by Robert Fludd

"Following a 'healthful diet pattern', which includes a variety of foods such as fruits, vegetables, oily fish, seeds, nuts, legumes, is known to be a good approach to chronic disease prevention rather than focusing on particular nutrients."
"This is important because the public might wrongly think about the term 'antioxidant' as a magic pill that will prevent the onset of dementia."
"It is important to remember that consuming isolated flavonols or extracts of flavonol-rich foods, for example tea extracts, will not work in isolation to reduce risk of disease but high doses can also have negative effects."
Dr.Ada Garcia, lecturer in public health nutrition, University of Glasgow

A link has been established to flavonols -- an antioxidant found in plant pigments and present in almost all fruits and vegetables, as well as tea -- and Alzheimer's avoidance, according to a new study out of Rush University in Chicago, led by Dr. Thomas Holland.

The researchers tracked more than 900 elderly people for an average of six years, to determine what they ate and drank, (through self-reporting), while monitoring who among them later developed Alzheimer's. Divided into five groups based on the amount of flavonol in their diet, those in the group (all of whom had an average age of 81) who ingested the most flavonols were 48 percent less likely to be afflicted with Alzheimer's disease.

About 16 to 20 milligrams per day was established as the average preferential amount of intake of flavonol. The study found that the lowest group's intake was 5.3 milligrams daily and that the highest group consumed on average 15.3 milligrams on a daily basis. Research previously undertaken had placed the quantity of flavonols in an average size cup of tea between eight and 15 milligrams. The recommendation is for three cups of tea daily to achieve maximum flavonol intake.

Fruits, vegetables, tea, wine may reduce risk of Alzheimer’s. (CP/Paul Chiasson)

Of the 186 people in the highest group, 28 (representing 15 percent), developed Alzheimer's, in comparison to 56 people (30 percent), of the 182 people in the lowest intake group. When researchers adjusted for other factors which could affect Alzheimer's dementia risk such as diabetes, previous heart attack, stroke and high blood pressure, the results were the same.

Flabonols were broken down into four types: isorhamnetin, kaempferol, myricetin and quercetin. In each category the top food contributors were pears, olive oil, wine and tomato sauce for isorhamnetin; kale, beans, tea, spinach and broccoli for kaempferol; tea, wine, kale, oranges and tomatoes for myricetin; and tomatoes, kale, apples and tea for quercetin.

Both a kale salad and a glass of wine are rich in flavonols, linked to a lower risk of Alzheimer's disease. (Andrew Purcell)

The flavonols with a high intake of isorhamnetin left people with a 38 percent less likelihood of developing Alzheimer's, while those with a high intake of kaempferol were 51 percent less likely to develop dementia, and those with a high intake of myricetin were also 38 percent less prone to developing dementia. The data did not prove however, that a link existed between flavonols and Alzheimer's.

The possibility is there that other properties common to products high in antioxidants good for the brain might be involved. But there is fairly well unanimous acknowledgement on the part of scientists in the field of public health nutrition that a variety of foods considered to be high in nutritional value with a focus on fruits, vegetables, fish seeds, nuts and legumes represent the pathway to optimum health outcomes.

Eating more fruits and vegetables and drinking more tea could be a fairly inexpensive and easy way for people to help stave off Alzheimer's dementia, say researchers.