The study – published in the journal Hypertension – found no evidence to suggest that fructose increases blood pressure when it is eaten for more than seven days, despite previous research revealing that fructose consumption leads to immediate rises blood pressure.
In fact, the researchers, led by Dr David Jenkins and Dr John Sievenpiper, observed a significant decrease in diastolic blood pressure 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 – first author of the review.
"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," she said.
She explained, for example, that we know people are consuming more soft drinks than ever, “but is it the fructose, the extra calories, or possible other factors that are adding to their illnesses?”
Fructose is a simple monosaccharide sugar that is found in many foods. Fruits are the primary source of naturally occurring fructose, though the molecule found in fruits and vegetables is the same found in high-fructose corn syrup that is used in processed foods and beverages.
The researchers noted that previous research has raised concerns over possible adverse effects of fructose on blood pressure.
Last year research data from over 2500 people from the United States and the UK found that high intakes of sugar sweetened beverages are linked with increases in blood pressure – whilst a meta-analysis of 11 research trials found links between consumption of the sugar and diabetes risk to be “clear and consistent.”
In the new review and meta-analysis, Ha and her 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 consumed an average of 78.5g of fructose every day for around four weeks.
Ha and her colleagues reported overall that fructose intake in isocaloric exchange for other carbohydrates significantly decreased diastolic and arterial pressure.
“There was no significant effect of fructose on systolic blood pressure,” they added.
“Contrary to previous concerns, we found that isocaloric substitution of fructose for other carbohydrates did not adversely affect blood pressure in humans,” said the authors.
They added that longer and larger research trials are now needed to confirm the results of their systematic review.
Published online ahead of print, doi: 10.1161/HYPERTENSIONAHA.111.182311
“Effect of Fructose on Blood Pressure: A Systematic Review and Meta-Analysis of Controlled Feeding Trials”
Authors: V. Ha, J.L. Sievenpiper, R.J. de Souza, L. Chiavaroli, D.D. Wang, et al