Avoid Alzheimer’s – drink your juice!
Recent studies have suggested that antioxidant vitamins from fruits and vegetables (not from supplements) may help delay the onset of Alzheimer's disease. Other than vitamins, the most abundant source of antioxidants in foods are substances known as polyphenols that are primarily found in the skin or rind of fruits and vegetables. The method of preparation of these foods then has a big impact on the amount of polyphenols in the resulting cooked food.
We know that beverages like tea, wine, and juices are major sources of polyphenols in the diet, and some studies have shown that wine consumption, but not tea consumption, may also contribute to a reduced risk of Alzheimer's. Yet no study, until recently, had focused on fruit and vegetable juice consumption and risk of Alzheimer's, even though commercial fruit and vegetable juices, which are made from frozen concentrates, are known to be high in polyphenols due to the high extracting pressure used in commercial preparation (Am J Med 2006(9):119;751-759).
Researchers at Vanderbilt University made use of a study known as the Kame Project, which followed 1,985 Japanese persons from 1992 to 2001. The cross-cultural study was created to assess Alzheimer's disease and vascular dementia among Japanese persons in Hiroshima, Japan; Oahu, Hawaii; and Seattle, Washington. Of those subjects in the study, 1,836 were found to be free of dementia symptoms at the beginning of the study and were included in the sample for the scientists at Vanderbilt.
They found that regardless of whether the subjects smoked, drank tea, how much they exercised or how much fat they ate, there was a strong inverse relationship between how much juice they drank (3 or more times per week) and their incidence of Alzheimer's disease. Those who drank the most juice had a reduced risk of Alzheimer's of 76%!
Also interesting is their finding that dietary intake of vitamins E, C, and beta-carotene were not related to the risk of Alzheimer's, nor was tea drinking.
What this means for you:
Once again, it's better to eat the food than take the supplements. Indeed, we know that too much Vitamin E can be bad for you. Better to get your polyphenols the old-fashioned way - by drinking them. The researchers note that they did not collect information on which juices in particular the study participants drank, but certainly orange juice or grapefruit juice is full of vitamins and can often be found fortified with calcium. Like your Mom probably said: Drink your juice!