There’s some promising news on the Alzheimer’s front – higher consumption of fruits, vegetables, and their derivatives such as tomato sauce, olive oil, and wine may help prevent Alzheimer’s dementia. Published in the journal Neurology in January, the study followed dementia-free volunteers from the Rush Memory and Aging Project, a community-based project of Rush University in Chicago, for a mean of six years. Out of 921 participants with an average age of 81 and 75% of whom were female, 220 developed Alzheimer’s. Each participant underwent an annual neurological examination and filled out a detailed food questionnaire regarding the frequency with which they consumed 144 different food and beverage items in the previous 12 months.
Researchers monitored intakes of four different types of flavonols: kaempferol, quercetin, isorhamnetin and myricetin. Flavonols are a class of flavonoids, a diverse group of more than 6,000 types of phytochemicals (plant biochemicals) found in most fruits and vegetables. Flavonoids, along with carotenoids (orange, yellow and red pigments), give fruits and vegetables their bright colors. Flavonoids contain high levels of free radical scavenging antioxidants and have anti-inflammatory effects.
After adjusting for age, sex, educational attainment, physical activity levels, genetics, and later-life cognitive activity, participants with the highest one-fifth of flavonol intake had a 48% reduced incidence of Alzheimer’s over the study period compared with those in the lowest one-fifth of flavonol intake. Intake of kaempferol, found in kale, beans, tea, spinach, and broccoli, was associated with the greatest reduction (51%) in Alzheimer’s. Myricetin, found in tea, wine, kale, oranges, and tomatoes, and isorhamnetin, found in pears, olive oil, wine, and tomato sauce, were both associated with a 38% reduction in Alzheimer’s dementia.
Quercetin, found in tomatoes, kale, apples, and tea, offered no protective effect at all against Alzheimer’s.
Flavonols are available as dietary supplements. However, lead author Dr. Thomas Holland, of Rush University College of Health Sciences, told the New York Times that it’s best to get flavonols from food.
“You get a broader intake of vitamins, minerals and bioactives in food than in the supplements,” Holland said.