Eating two teaspoons of nuts a day may help to keep dementia at bay, according to a long-term study on over 4,800 Chinese adults from the University of South Australia.
, recently published in , examined the data of Chinese people aged 55-plus over the course of 15 years to determine whether nut consumption can protect the brain from cognitive decline and neuro-degenerative illnesses like dementia.
The results showed that eating more than two teaspoons (or 10 grams) of nuts every day was positively associated with better mental functioning, including improved thinking, reasoning and memory.
“By eating more than 10 grams of nuts per day older people could improve their cognitive function by up to 60 per cent compared to those not eating nuts,” the study’s lead researcher, , says. “This can effectively [ward] off what would normally be experienced as a natural two-year cognition decline.”
The results showed that eating more than two teaspoons (or 10 grams) of nuts every day was positively associated with better mental functioning, including improved thinking, reasoning and memory.
Peanut was the nut variety most frequently eaten by adults in the study, accounting for over 80 per cent of consumption. Peanuts were eaten fresh, roasted or fried.
Other nuts consumed by the study’s participants included walnut, chestnut, pine nut, almond and hazelnut.
However, Dr Li tells SBS the kind of nut consumed is irrelevant to the results. She believes that all nuts grown locally to the consumer could deliver the same brain health benefit.
“China is such a large country with lots of regional food variations but nuts are grown and available in lots of places. We have a local production of peanuts and walnuts, grown as natural products in our own soil. So from this point, we see a philosophy arise: to be at harmony with your own environment.
“You don’t have to go and buy expensive [foreign] nuts. Eat whatever nuts are grown locally to you, because they will be a good source of common nutrients.”
explains that the study’s results are significant to both Chinese and non-Chinese adults across the globe because of the increasing worldwide prevalence of dementia.
“In the past few decades, we’ve seen the ageing of the Chinese population but one public health concern is emerging: dementia and cognitive impairment. [Meanwhile], Australia has already defined as an ageing society. So dementia and cognition decline are already an issue in both countries.”
estimates the number of people living with dementia is 47 million, globally. By 2030, this is projected to rise to 75 million.
China currently has one of the world’s fastest growing ageing populations. In , with the ratio of young to old dramatically imbalanced by the rising ranks of the elderly. of people with dementia.
You don’t have to go and buy expensive [foreign] nuts. Eat whatever nuts are grown locally to you, because they will be a good source of common nutrients.
According to , 447,115 Australians are estimated to be currently living with dementia. The organisation claims that without a medical breakthrough, the number of people with dementia will increase to 589,807 by 2028.
“No matter whether this study [was conducted] in the East or West part of the globe, the one thing that is common everywhere is nuts are beneficial,” Dr Li explains. “The association demonstrated in this study shows that nuts are protective of your brain.”
Why do nuts protect your brain?
Another study led by UniSA, published in looked at the consumption of peanuts and their effect on cognition.
The 12-week randomised crossover trial was conducted on overweight Australians aged 50-75 years. It suggested that consuming 56-84 grams a day of peanuts increased middle cerebral artery, the elasticity of small artery and cognitive function. The study concludes that regular peanut consumption improved cerebrovascular and cognitive function.
So what’s in a nut that makes it good for our brains?
While there is no cure for age-related cognition decline and neuro-degenerative disease, variations in what people eat are delivering improvements for older people.
Dr Li tells SBS, nuts have specific anti-inflammatory and antioxidant effects, which can alleviate and reduce cognitive decline.
Nuts are also known to be high in healthy fats, protein and fibre with nutritional properties that can lower cholesterol and improve cognitive health.
“While there is no cure for age-related cognition decline and neuro-degenerative disease, variations in what people eat are delivering improvements for older people.”
More research is needed to prove cause and effect, to determine which nut is the best for brain health and specific dietary interventions using nuts to delay or prevent the onset of dementia.