Prolonged fructose intake not linked to rise in blood pressure: study

A new study has found that despite previous research showing blood pressure rose in humans immediately after they consumed fruit sugar – also known as fructose -- there is no evidence fructose increases blood pressure when it has been eaten for more than seven days.

In fact, researchers led by U of’T University Professor David Jenkins, Canada Research Chair in Nutrition and Metabolism, and John Sievenpiper of St. Michael’s observed a significant decrease in diastolic blood pressure – the measure of blood pressure when the heart is relaxed between contractions– in people who had eaten fructose for an extended period of time.

“A lot of health concerns have been raised about fructose being a dietary risk factor for hypertension, which can lead to stroke, cardiovascular disease, renal disease and death,” said Vanessa Ha, a U of’T master of nutritional sciences student and the lead author of the paper. “However, we wanted to determine whether fructose itself raised blood pressure, or if the apparent harm attributed to fructose was simply because people are eating too many calories.”

The study looked at the effect of all sources of fructose, including natural and crystalline. Fruits are the primary source of naturally occurring fructose, and the fructose molecule found in fruits and vegetables is the same fructose found in high-fructose corn syrup. Crystalline fructose is a processed form which has added water and trace minerals.

In the systematic review and meta-analysis, Ha and colleagues pooled the results of 13 controlled feeding trials which investigated the effects of fructose on blood pressure in people who had ingested fructose for more than seven days.

The 352 participants included in their analysis ate an average of 78.5g of fructose every day for about four weeks. The U.S. average is an estimated 49g per day.

The paper is published in the Feb. 13 edition of Hypertension, a journal of the American Heart Association.

Professor Bryan Spencer, academic director, Statistics Canada Research Data Centre at McMaster University, explores the data and draws conclusions.