Walnuts for Memory
This cross-sectional study evaluated whether antioxidant-rich foods from the Mediterranean diet were associated with better cognitive performance in a subsample (447) of elderly participants (aged 55-80 years) from the landmark Spanish PREDIMED study -- a dietary intervention trial in asymptomatic individuals with high cardiovascular risk. The researchers evaluated the intake of various foods and performed neuropsychological tests to assess cognitive function in relation to diet, and analyzed the urinary excretion of polyphenols as a biomarker of daily intake of antioxidants.
The study reported regular consumption of walnuts, but not of other nuts, was associated with better working memory. The investigators believe that the high polyphenol (antioxidant) content found in walnuts may be one of the key elements in helping to preserve cognition and fight age-related cognitive decline. Coffee, virgin olive oil and wine were also associated with better cognitive scores.
Study investigator and author Dr. Emilio Ros, Hospital Clinic of Barcelona, affirms the "future study of the nearly 7,500 participants of the PREDIMED trial will provide firmer evidence regarding the potential of the Mediterranean diet and its components (among them walnuts) to reduce the incidence of neurodegenerative diseases, including Alzheimer's." An estimated 5.1 million Americans suffer from Alzheimer's disease, and although there is no known cure, research continues to uncover the role dietary patterns can play in the development and progression of the illness.
Walnuts are a nutrient-dense whole food that not only provide antioxidants, but also alpha-linolenic acid (ALA), the plant-based omega-3 fatty acid. These nutrients offer anti-inflammatory properties and protect brain cells from oxidative damage. Previously reported research by Dr. Abha Chauhan: head, Developmental Neuroscience Lab, NYS Institute for Basic Research in Developmental Disabilities, showed walnuts to have protective effects against oxidative stress and cell death caused by beta amyloidal protein (Aß), the main component of amyloid deposits and senile plaques in the brains of individuals with Alzheimer's disease.
According to Chauhan, "Collectively, the findings of our previous studies and the current study by Ros' group suggest that a diet with walnuts may reduce the risk of dementia in the elderly population. This may be attributed to a unique combination of anti-amyloidogenic, antioxidant and anti-inflammatory properties of walnuts."
From the February 28, 2012, Prepared Foods' Daily News.