Potatoes have been a dietary staple for as long as anyone can remember, but the data from some new research may make us re-think our spud-love. The study, examining the diets of people eating four or more servings of potatoes a week, was just published in the BMJ. It found that the potato lovers had an increased risk of high blood pressure.

Researchers at Brigham and Women’s Hospital and the Harvard Medical School found those who replaced one serving of boiled, baked, or mashed potatoes per day with a non-starchy vegetable had a lower risk of hypertension.

“Potatoes are very nutrient rich for sure, but one should also know they’re very high on the glucose index,” said lead study researcher Dr. Lea Borgi, a physician at Brigham.

The research team followed over 187,000 men and women from three large US studies for more than 20 years. Dietary intake, including frequency of potato consumption, was assessed using a questionnaire. Hypertension was reported by participants based on diagnosis by a health professional.

After taking account of several other risk factors for hypertension, the researchers found that four or more servings a week of baked, boiled, or mashed potatoes was associated with an increased risk of hypertension compared with less than one serving a month in women, but not in men. Higher consumption of French fries was also associated with an increased risk of hypertension in both women and men. However, consumption of potato chips was associated with no increased risk.

The researchers believe that their findings "have potentially important public health ramifications, as they do not support a potential benefit from the inclusion of potatoes as vegetables in government food programs but instead support a harmful effect that is consistent with adverse effects of high carbohydrate intakes seen in controlled feeding studies."

"We will continue to rely on prospective cohort studies, but those that examine associations between various dietary patterns and risk of disease provide more useful insights for both policy makers and practitioners than does a focus on individual foods or nutrients," they conclude.