Eating grapes two times a day for six months kept dramatic metabolic decline in areas of the brain related to Alzheimer's disease at bay in individuals diagnosed with early memory decline.
In a study published in the journal Experimental Gerontology, researchers from the University of California, Los Angeles showed that aside from grapes offering protective benefit for Alzheimer's-related parts of the brain, the fruit also had a hand in facilitating metabolism in other brain areas related to working memory and attention.
According to lead investigator Daniel H. Silverman, the study examined grapes as whole fruit, and the results they got suggest regularly consuming the fruit may provide protective effects against premature mental decline associated with Alzheimer's disease.
He also said that the results of the pilot study add to growing evidence supporting grapes' beneficial role in cardiovascular and neurologic health. However, Silverman stressed that more clinical studies will have to be carried out, preferable with a larger number of subjects, to confirm the protective benefits observed in grapes against Alzheimer's disease.
All subjects in the study were experiencing memory decline, and each one was randomly assigned to receive either whole grape powder or a placebo powder free of polyphenol. The whole grape powder contained the same amount of grape as two and a quarter cups of the fruit.
At baseline and six months later, cognitive performance and brain metabolism changes were also measured. The researchers assessed brain metabolism changes with help from PET scans, a common tool used by doctors to evaluate individuals showing dementia symptoms.
According to results, eating grapes maintained healthy metabolic activity in brain regions affected by Alzheimer's disease's earliest stages, where metabolic decline starts taking hold. Subjects who were given placebo exhibited dramatic metabolic decline in critical brain regions and didn't show improvements in brain processes related to working memory and cognition.
Why Do Grapes Work?
According to the researchers, polyphenols in grapes have antioxidant and anti-inflammatory effects. Earlier works suggest that the fruit is good for brain health in several ways, including such as promoting the flow of blood to the brain to maintain ideal chemical levels by reducing oxidative stress.
Alzheimer's Disease Statistics
Currently, there are 5.4 million Americans living with the condition, 5.2 million of which are estimated to be 65 years old and above, while 200,000 are afflicted by early-onset Alzheimer's. Diagnoses for the disease continue to grow as one person develops the condition every 66 seconds, and this will double by mid-century as one person in the United States develops Alzheimer's disease every 33 seconds, according to the Alzheimer's Association.
It's the sixth leading cause of death in the United States and accounted for $236 billion in health care costs in 2016. Almost one in every five Medicare dollars is spent on Alzheimer's disease and other forms of dementia, and this amount is expected to rise to one in every three dollars by 2050.
Alzheimer's disease is a relatively well-known condition, but it is still not clear what causes it exactly. Researchers, however, believe that it's a combination of lifestyle, environmental, and genetic factors.