12 February 2020 - MedicalXpress - Nutrition a key ingredient for psychological health in Canadian adults

A new study investigating factors that contribute to psychological distress in adults has found that that risk of malnourishment is linked to psychological distress among Canadians aged 45 years and older.

"These findings are consistent with other research which has found links between poor quality diet, and depression, bipolar disorder, and psychological distress," says study lead Dr. Karen Davison, Health Science faculty member at Kwantlen Polytechnic University in Surrey, BC. "Collectively, they indicate that nutrition may be an important consideration in mental health care."

Adults who have insufficient appetite, face challenges in preparing food, or consume low-quality diets are identified to be at risk of malnourishment. Indicators of a poor diet found in the study that were associated with psychological distress included low fruit and vegetable intake and higher levels of chocolate consumption.

Given that lower grip strength is a measure of poor nutrition, the researchers also explored the relationship between grip strength and psychological health. Men with low grip strength had 57% higher odds of psychological distress.

"This finding is consistent with previous studies which suggests that psychological problems such as depression are associated with an increased risk of frailty" says co-author Shen (Lamson) Lin, a doctoral student at University of Toronto's Factor Inwentash Faculty of Social Work (FIFSW).

Other factors associated with psychological distress among older Canadians

In addition to nutrition indicators, other factors found to be associated with psychological distress include chronic pain, multiple physical health problems, poverty and immigrant status.

One in five older adults with three or more chronic health problems were in distress compared to one in 17 who did not have any chronic conditions. One-third of women and one-quarter of men in chronic pain were in distress.

"Distress is common among those experiencing uncontrollable and chronic pain. Furthermore, dealing with multiple physical health problems can be upsetting and can make day-to-day activities, work and socializing much more difficult." says senior author, Esme Fuller-Thomson, professor at FIFSW and director of the Institute for Life Course & Aging. Fuller-Thomson is also cross-appointed to the Department of Family and Community Medicine and the Faculty of Nursing.

The prevalence of distress was highest among the poorest respondents; One in three older adults who had a household income under $20,000 per year were in distress.

"It is not surprising that those in poverty were in such high levels of distress: Poverty is a chronic and debilitating stressor. It can often be challenging even to pay one's rent and put healthy food on the table. Poverty may also result in poorer housing and neighborhood quality, and greater residential turnover which are also stress-inducing," says co-author Yu Lung, a doctoral student at FIFSW.

The study also found that immigrant women living in Canada less than 20 years had a higher prevalence of distress than women who were Canadian-born residents (21% vs 14%).

"Unfortunately, this survey did not identify the reasons for the greater distress among immigrant women, but we hypothesize that it may be due to the difficulties of resettling in a new country, such as language barriers, financial strain, complications of having one's qualifications recognized, distance from family and other social support networks and perceived discrimination" says co-author Hongmei Tong, Assistant Professor of Social Work at MacEwan University in Edmonton.

"Although immigrant men also face many of these settlement problems, they were not at elevated risk of distress compared to their Canadian-born peers," says co-author Karen Kobayashi, Professor in the Department of Sociology and a Research Affiliate at the Institute on Aging & Lifelong Health at the University of Victoria. "One idea we hope to explore in future research is whether these gender differences could be due to the fact that the husbands initiated the immigration process and the wives may have had limited or no say in the decision to leave their homeland."

The study team analyzed data from the Canadian Longitudinal Study on Aging which included 25,834 men and women aged 45-85 years. The article was published this month in the Journal of Affective Disorders.

"The team's findings suggest that policies and health care practices should aim to reduce nutrition risk, improve diet quality, address chronic pain and health problems and poverty among those experiencing poor mental health," adds Dr. Davison. "Given that mental health conditions place a large burden of disability worldwide, such program and policy changes are becoming critically important."