A new longitudinal study suggests eating fruit and vegetables appears to convey a level of protection against psychological stress for women more so than men.
University of Sydney researchers followed more than 60,000 Australians aged 45 years and older. Investigators measured participants fruit and vegetable consumption, lifestyle factors, and psychological distress for the period 2006-08 and then in 2010.
Psychological distress was measured using the Kessler Psychological Distress Scale, a 10-item questionnaire measuring general anxiety and depression. Usual fruit and vegetable consumption was assessed using short validated questions.
“This study shows that moderate daily fruit and vegetable consumption is associated with lower rates of psychological stress,” said Dr. Melody Ding of the University of Sydney’s School of Public Health.
“It also reveals that moderate daily vegetable intake alone is linked to a lower incidence of psychological stress. Moderate fruit intake alone appears to confer no significant benefit on people’s psychological stress.”
These new findings are consistent with numerous cross sectional and longitudinal studies showing that fruit and vegetables, together and separately, are linked with a lower risk of depression and higher levels of well-being assessed by several measures of mental health.
“We found that fruit and vegetables were more protective for women than men, suggesting that women may benefit more from fruit and vegetables,” said first author and University of Sydney Ph.D. student, Binh Nguyen.
The investigators say further studies should investigate the possibility of a threshold between medium and higher levels of fruit and vegetable intake and psychological stress.
- people who ate three to four daily serves of vegetables had a 12 percent lower risk of stress than those who ate zero to one serves daily;
- people who ate five to seven daily serves of fruit and vegetables had a 14 percent lower risk of stress than those who ate zero to four serves daily;
- women who ate three to four daily serves of vegetables had an 18 percent lower risk of stress than women who ate zero to one serves daily;
- women who ate two daily serves of fruit had a 16 percent lower risk of stress than women who ate zero to one serves daily;
- women who ate five to seven daily serves of fruit and vegetables had a 23 percent lower risk of stress than women who ate zero to one serves daily.
At the start of the study, characteristics associated with higher stress included: being female, younger, having lower education and income, being overweight/obese, a current smoker, and being physically inactive.
Interestingly, fruit consumption alone had no significant association with a lower incidence of stress. Moreover, there was no significant association between higher levels of fruit and vegetable intake (greater than seven daily serves) and a lower incidence of stress.
Source: University of Sydney/EurekAlert