SAN DIEGO—High fructose intake may be significantly and independently associated with higher BP in adults with no previous history of hypertension, researchers reported here at Renal Week 2009.
The finding suggests that cutting back on processed foods and beverages that contain high fructose corn syrup (HFCS) may help prevent development of hypertension.
Americans consume 30% more fructose today compared with 20 years ago and up to four times more than 100 years ago. While this increase mirrors a dramatic rise in the prevalence of hypertension, studies have been inconsistent in linking excess fructose in the diet to hypertension.
Researchers at the University of Colorado Denver Health Sciences Center studied the issue in a large representative population of 4,528 U.S. adults 18 years of age and older with no prior history of hypertension. Subjects were participants in the National Health and Nutrition Examination Survey (2003-2006).
Fructose intake was calculated based on a dietary questionnaire, and foods such as fruit juices, soft drinks, bakery products, and candy were included. Fruits were excluded from the calculation because of their high content of ascorbate, antioxidants, and potassium that counter the effects of fructose.
The median daily fructose intake per day for the study population was 74 grams, the equivalent of consuming 2.5 sugary soft drinks a day (12 ounces per drink). Compared with participants who consumed less than 74 grams of fructose per day, those who ate or drank 74 grams or more of fructose per day had a 28%, 36%, and 87% greater risk of having BP levels of 135/85 mm Hg or higher, 140/90 mm Hg or higher, and 160/100 mm Hg or higher, respectively.
Investigators adjusted for demographics, comorbidities, physical activity, total caloric intake, and dietary confounders such as salt and vitamin C intake, and the findings still remained and were consistent throughout.
The researchers, led by Diana Jalal, MD, said additional studies are needed to determine if low fructose diets can normalize BP and prevent development of hypertension.
“Several mechanisms of action have emerged as plausible explanations over the last few years,” said Dr. Jalal, Assistant Professor of Medicine. “They include the fact that fructose can suppress nitric oxide production by the vascular cells and fructose can increase uric acid production, which in turn raises blood pressure.” Fructose has also been shown to cause animals to increase salt absorption through the gut and decrease renal excretion of salt, she said.