The 20-year cohort study followed more than 83,000 healthy nurses from a pool of about 116,000 who filled out questionnaires every two years and which found significant reductions in self-reported hypertension occurred better when diets and lifestyles were pursued.
Hypertension is thought to be the biggest contributor to preventable death in the US among women.
The researchers found only 37 per cent of women with hypertension had controlled blood pressure compared to 57 per cent taking pharmaceutical treatments.
“Primary prevention of hypertension, therefore, would have major positive public health ramifications,” the researchers wrote.
Factors leading to hypertension included obesity; alcohol and tobacco use and dietary factors such as low folic acid intake.
Low-risk factors for hypertension were a Body mass Index (BMI) of less than 25; an average of 30 minutes exercise per day; a good diet as measured by the Dietary Approaches to Stop Hypertension (DASH); alcohol intake of less than 10g per day; use of nonnarcotic analgesics once per day; and intake of at least 400ug per day of folic acid per day.
Over the 20 year period, 12,319 hypertension cases were detected among the population of 27 to 44-year-old nurses – or approximately 15 per cent of the population.
Younger nurses who took more than 1000ug/d of folic acid were found to have 46 per cent less chance of developing hypertension, 18 per cent for older nurses.
Among women who had negligible dietary intake of folic acid in their regular diets, supplementation was shown to significantly reduce hypertension risk.