Written by Jessica Patella, ND. In research in 121,700 middle aged nurses, the intake of berries delayed cognitive decline by up to 2.5 years due to its oxidative properties. 

Americans aged 65 years and older make up the largest portion of the population (3). It is important for public health reasons to recognize health problems that occur more often in this age group. Recent research found that high intakes of berries, specifically strawberries and blueberries, might delay  cognitive decline that affects the aging American population.

The research began in 1980 with 121,700 female registered nurses, aged 30-55 years. Questionnaires were sent out every other year on their health, lifestyle and food intakes. From 1995-2001 the women who had reached 70 years old or older also were given a cognitive function test (n=19,415). A second cognitive test was given about two years later and a third cognitive test was given after another two years (1).

According to the questionnaire responses, blueberries and strawberries were the main foods that contributed to the most antioxidant intake. Of all the foods, tea, apples, oranges, berries and onions accounted for over 80% of the total antioxidant intake (1).

Results showed that women with higher berry intake (greater than two servings of strawberries and greater than one serving of blueberries per week) had delayed cognitive aging by up to 2.5 years (1). This was the first epidemiological study to show that long-term consumption of berries was related to the slower rate of cognitive decline (1).

The delayed cognitive decline could be due to anthocyanidins in the berries (1). Anthocyanidins are what give berries their color and are a type of antioxidant. Anthocyanidins are unique in the fact they can cross the blood-brain barrier and localize in areas of the brain involved in learning and memory, therefore delaying cognitive decline (1,2).

In conclusion, higher consumption of berries is associated with a delay in cognitive decline in women (1). Further research including men should be considered. Also, it is important to note that self-reported dietary questionnaires can be unreliable (1). A more controlled study with specific levels of berry and/or antioxidant intake should also be considered.

Source: Devore, Elizabeth E., et al. “Dietary intakes of berries and flavonoids in relation to cognitive decline.” Annals of neurology 72.1 (2012): 135-143.

© 2012 American Neurological Association 

Posted May 15, 2012.

Jessica Patella, ND, is a naturopathic physician specializing in nutrition and homeopathic medicine and offers a holistic approach to health. 

References:

  1. Devore EE, et al. Dietary Intakes of Berries and Flavonoids in Relation to Cognitive Decline.  Ann Neurol 2012.  Doi: 10.1002/ana.23594
  2. Andres-Lacueva C,  et al. Anthocyanins in aged blueberry-fed rats are found centrally and may enhance memory. Nutr Neurosci 2005;8:111–120.
  3. US Census, see the United States Census Bureau website.