Good sleep patterns can help men live longer - but women will only benefit if they also have a diverse diet, a new study shows.
The Monash University-led collaborative study found that women who ate a varied diet that included sources rich in vitamin B6 could still live long lives despite poor sleep habits.
The researchers from Monash University, the National Defense Medical Centre, Taiwan, and the National Health Research Institutes, Taiwan, investigated the ways diet contributed to the relationship between sleep quality and mortality among elderly men and women.
Emeritus Professor Mark Wahlqvist from Monash University's Department of Epidemiology and Preventive Medicine and the Monash Asia Institute said sleep played a more important role in men's mortality than women's.
"We found that for both genders, poor sleep was strongly correlated with poor appetite and poor perceived health.
"There was significant interaction between sleep quality and dietary diversity. For men, poor sleep was not associated with a greater risk of death unless there was also insufficient dietary diversity. For women, good sleep only provide a survival advantage if they had a diverse diet."
The study found women were almost twice as likely as men to sleep badly. Women who were poor sleepers had a lower intake of vitamin B6 from food than those whose sleep was rated fair or good. Fair sleepers had lower iron intakes than good sleepers.
Both men and women could improve their outlook by eating a more varied diet.
"Sufficient dietary diversity in men could offset the adverse effect on mortality of poor sleep while women need to make sure they are eating foods high in vitamin B6," Professor Walhqvist said.
Professor Wahlqvist said people who did not sleep well were also less able to chew, had poor appetites, and did less physical activity.
"These characteristics could contribute to lower overall dietary quality and food and nutrient intake, especially for vegetables, protein-rich foods, and vitamin B-6," Professor Wahlqvist said.
"They may also contribute to the risk of death, either in their own right or together with problematic sleep. Intervention focusing on education on healthy dietary practices in elderly people could improve sleep duration and provide more stable levels of health."
The study was recently published in the Journal of the American College of Nutrition.