Consumption of at least two servings of walnuts every week may be associated with healthy ageing among women, a study claims.
"Healthy aging" was defined as longevity with sound mental health and no major chronic diseases, cognitive issues or physical impairments following the age of 65.
Researchers, including those from Bordeaux Population Health Research Center in France, found that women in their late 50s and early 60s who consumed at least two servings of walnuts per week had a greater likelihood of healthy ageing compared to those who did not eat walnuts
After accounting for various factors that could impact health in older adults, such as education and physical activity, walnuts were the only nut associated with significantly better odds of healthy ageing, according to the study published in the Journal of Aging Research.
Previous research from Francine Grodstein, formerly of Brigham and Women's Hospital in the US, found that eating walnuts may have a positive impact on reducing the risk for physical impairments in older adults as well as cognitive decline.
The research also found decreases in cardiovascular disease and type 2 diabetes -- all conditions that become more common as we age, the researchers said.
There is no one solution to slowing down the effects of ageing, but adopting the right habits, like snacking on a handful of walnuts, can help, they said.
In the latest study, Grodstein looked at data from 33,931 women in the US Nurses' Health Study (NHS) to evaluate the association between nut consumption and overall health and well-being in ageing.
Between 1998 and 2002, female nurses in the NHS were asked about their diet, including total nut consumption.
They were evaluated for chronic diseases such as cancer, heart attack, heart failure, stroke, type 2 diabetes and Parkinson's disease.
The nurses were assessed for memory concerns, mental health and physical limitations, including daily activities like walking one block, climbing a flight of stairs, bathing, dressing oneself and pushing a vacuum cleaner.
Of the study participants, 16 per cent were found to be "healthy agers," defined as having no major chronic diseases, reported memory impairment or physical disabilities as well as having intact mental health, the researchers said.
Although previous research has connected a healthy diet, including walnuts, to better physical function among older men and women, this study only included women, according to the researchers.
More research is needed to understand if these results hold true among men, they said.
Participants were not assigned to eat walnuts or other foods, and were simply asked about their dietary choices.
The researchers noted that it is possible that subjects misreported their dietary intake since this information was collected by questionnaires.
As an observational study, this does not prove cause and effect, according to the researchers.