The study – published in the journal Stroke– suggests that people who drink low-fat milk and eat reduced-fat yogurt and cheese have a lower risk of stroke compared to those who consume full-fat dairy counterparts.
Led by Dr Susanna Larsson from the Karolinska Institute in Sweden, the researchers analysed data from nearly 75,000 adults – finding that those who consumed low-fat dairy products had a 13% lower risk of ischemic stroke than those who ate high-fat dairy foods.
"This is the largest study to date to examine the association between consumption of total, low-fat, full-fat and specific dairy foods and the risk of stroke in adult men and women," said Larsson.
Northern Europeans and North Americans traditionally consume much more dairy foods than other global populations. So switching to low-fat dairy products could impact stroke risk for millions of people, she said.
"From a public health perspective, if people consume more low-fat dairy foods rather than high-fat dairy foods, they will benefit from a reduced risk of stroke and other positive health outcomes," she added.
Larrson and her team followed 74,961 Swedish women and men who were free from cardiovascular disease and cancer and who completed a 96-item food frequency questionnaire in 1997. The team then followed the incidence of stroke using the Swedish Hospital Discharge Registry.
During an average follow up of 10 years, the team reported to find 4089 cases of stroke,“including 3159 cerebral infarctions, 583 hemorrhagic strokes, and 347 unspecified strokes.”
They noted that consumption of low-fat dairy foods was inversely associated with risk of total stroke (P for trend=0.03) and cerebral infarction (P for trend=0.03).
“The multivariable relative risks for the highest compared with the lowest quintile of low-fat dairy consumption were 0.88 for total stroke and 0.87 for cerebral infarction,” said Lassson and her team.
“Consumption of total dairy, full-fat dairy, milk, sour milk/yogurt, cheese, and cream/crème fraiche was not associated with stroke risk,” they added, noting that the results do suggest that low-fat dairy consumption is inversely associated with the risk of stroke.
However, Lasson said that more research on the link between low-fat dairy consumption and risk of stroke is needed.
The authors added that benefits of low-fat dairy foods are probably due to the vitamins and minerals that such products contain, such as calcium, potassium, magnesium and vitamin D.
"It is possible that vitamin D in low-fat dairy foods may explain, in part, the observed lowered risk of stroke in this study because of its potential effect on blood pressure," said Larsson.
Published online ahead of print, doi: 10.1161/STROKEAHA.111.641944
“Dairy Consumption and Risk of Stroke in Swedish Women and Men”
Authors: S.C. Larsson, J. Virtamo, A. Wolk