Mushrooms’ Magic May Lie in Boosting Cognitive Health: Study
Cognition & Memory
If you love eating mushrooms, you may enjoy puzzle solving for a long time, as a new study shows that eating mushrooms can protect parts of the brain responsible for cognitive function.
New research has shown that seniors who consume more than two standard portions of mushrooms weekly may have 50 per cent reduced odds of having mild cognitive impairment (MCI), according to scientists from the Department of Psychological Medicine and Department of Biochemistry at the Yong Loo Lin School of Medicine at the National University of Singapore (NUS). The six-year study, which was conducted from 2011 to 2017, collected data from more than 600 seniors over the age of 60 living in Singapore.
The team defined one portion as only three-quarters of a cup of cooked mushrooms with an average weight of around 150 grams. Two portions would be equivalent to approximately half a plate. While the portion sizes act as a guideline, it was shown that even one small portion of mushrooms a week may still be beneficial to reduce chances of MCI.
“This correlation is surprising and encouraging. It seems that a commonly available single ingredient could have a dramatic effect on cognitive decline,” said lead author Lei Feng, assistant professor at the NUS Department of Psychological Medicine.
MCI is typically viewed as a mid-point, the stage between the cognitive decline of normal ageing and the more serious decline of dementia. Seniors with MCI often display some form of memory loss or forgetfulness and may also show deficit on other cognitive function such as language, attention and visuospatial abilities. However, the changes can be subtle, as they do not experience disabling cognitive deficits that affect everyday life activities, which is characteristic of Alzheimer’s and other forms of dementia.
“People with MCI are still able to carry out their normal daily activities. So, what we had to determine in this study is whether these seniors had poorer performance on standard neuropsychological tests than other people of the same age and education background,” explained Feng. “Neuropsychological tests are specifically designed tasks that can measure various aspects of a person’s cognitive abilities. In fact, some of the tests we used in this study are adopted from commonly used IQ test battery, the Wechsler Adult Intelligence Scale (WAIS).”
The researchers conducted extensive interviews and tests with the senior-aged study participants to determine an accurate diagnosis. “The interview yields demographic information, medical history, psychological factors, and dietary habits. A nurse measured blood pressure, weight, height, handgrip, and walking speed. They also performed a simple screen test on cognition, depression, anxiety,” said Asst Prof Feng. Afterwards, the participants underwent a two-hour standard neuropsychological assessment along with a dementia rating.
The study volunteers consumed six common mushrooms—golden, oyster, shiitake and white button mushrooms, as well as dried and canned mushrooms.
The researchers noted that they believe the reason for the reduced prevalence of MCI in the seniors who ate mushrooms regularly may be due to a specific compound found in almost all varieties—ergothioneine (ET). A 2016 published study by the team on elderly Singaporeans revealed that plasma levels of ET in those with MCI were significantly lower than age-matched healthy individuals. The study led to the belief that a deficiency in ET may be a risk factor for neurodegeneration and increasing ET intake through mushroom consumption might possibly promote cognitive health.
Meanwhile, according to the researchers, other mushroom compounds such as certain hericenones, erinacines, scabronines and dictyophorines may also be advantageous for decreasing the risk of cognitive decline, as they may promote the synthesis of nerve growth factors. Bioactive compounds in mushrooms may also protect the brain from neurodegeneration by inhibiting production of beta amyloid and phosphorylated tau, and acetylcholinesterase.
Reference:
Feng, et al. “The Association between Mushroom Consumption and Mild Cognitive Impairment: A Community-Based Cross-Sectional Study in Singapore.” Journal of Alzheimer’s Disease, 2019; 1 DOI: 10.3233/JAD-180959.
