Sugar-sweetened beverages linked to increased BP, finds JAHA Study

Canada: Whether sugar raises blood pressure (BP) or not depends on the food source, suggests a recent study in the Journal of the American Heart Association. According to the study, while sugar-sweetened beverages are linked to an increased BP, healthier foods such as whole fruit, or low-fat yoghurt or a whole-grain cereal that contain sugars do not share the same relationship. In fact, they may have a protective role when it comes to high BP. Further, the study found no association for foods such as dairy desserts, fruit drinks, and sweet snacks.

"We identified the following associations of food intake with incident hypertension: harmful: sugar‐sweetened beverages; protective: fruit, yoghurt, and 100% fruit juice (moderate dose only); and no association: dairy desserts, fruit drinks, and sweet snacks," wrote the authors.

It is already known that hypertension (high BP) is a major risk factor for the development of cardiovascular diseases. The global prevalence of hypertension has been increasing. This increase has been attributed to unhealthy dietary choices, according to WHO. Fructose and fructose‐containing sugars have been identified as a dietary contributor to the development of high BP. "The suggested mechanism is thought to involve uric acid, whereby high intakes of fructose raise uric acid, which, in turn, activates the renin‐angiotensin system and inhibits the nitric oxide system, leading to hypertension," wrote the authors.

Sugar‐sweetened beverages (SSBs) are a major source of fructose. Although some studies have shown a consistent relationship between SSBs and incident hypertension, the same has not been shown for fructose‐containing sugars that contain independent of food form. The association for other important food sources of fructose-containing sugars, such as fruit and fruit-based products, grain and grain-based products, dairy and dairy-based based products sand sweets and desserts is unclear. To address this gap, John L. Sievenpiper, St. Michael's Hospital, Toronto, Canada, and colleagues conducted a systematic review and meta-analysis of prospective cohort studies of the relation of important food sources of fructose-containing sugars and incident hypertension.

The researchers searched the online databases for eligible studies through December week 2, 2018. For each food source, natural log‐transformed risk ratios (RRs) for incident hypertension were pooled using pair‐wise meta‐analysis and linear and nonlinear dose‐response meta‐analyses.

The researchers identified 26 reports, including 15 prospective cohorts (930 677 participants; 363 459 cases).

Read Also: Soft drinks- sugared or artificially sweetened associated with risk of increased mortality risk: JAMA

Key findings of the study include:

• Sugar‐sweetened beverages showed harmful (RR_{per‐355‐mL}) whereas fruit (RR_{per‐240‐g}) and yoghurt showed protective associations (RR_{per‐125‐g}) with incident hypertension throughout the dose range.


• One hundred per cent fruit juice showed a protective association only at moderate doses (RR_{at‐100‐mL}).


• The pair‐wise protective association of dairy desserts was not supported by linear dose‐response analysis.


• Fruit drinks or sweet snacks were not associated with hypertension.


• The certainty of the evidence was “low” for sugar‐sweetened beverages, 100% fruit juice, fruit, and yoghurt and “very low” for fruit drinks, sweet snacks, and dairy desserts.

"Many dietary guidelines for sugar are based on evidence that sugar-sweetened beverages are harmful, but we shouldn't necessarily extrapolate that to whole fruit, or low-fat yoghurt or a whole-grain cereal that contains sugars. The results should provide some relief to consumers and patients concerned about high blood pressure, and who may count teaspoons of sugars in the many foods they eat over the course of a day," wrote the authors.

"Overall, this study showed that only sugar‐sweetened beverages as a food source of fructose‐containing sugars have a harmful association with incident hypertension," concluded the authors.

The study, "Important Food Sources of Fructose‐Containing Sugars and Incident Hypertension: A Systematic Review and Dose‐Response Meta‐Analysis of Prospective Cohort Studies," is published in the Journal of the American Heart Association.

DOI: https://doi.org/10.1161/JAHA.118.010977