Sugar-sweetened beverage, sugar intake of individuals, and their blood pressure: international study of macro/micronutrients and blood pressure
Brown IJ, Stamler J, Van Horn L, et al. Hypertension. 2011;57(4):695-701.
In a recent paper, Brown et al. 1 reported cross-sectional associations between sugar-sweetened beverages (SSB) or specific sugars (fructose, glucose and sucrose) and blood pressure (BP) for participants in the International Study of Macro/Micronutrients and Blood Pressure (INTERMAP). The authors lend their support to recent recommendations by the American Heart Association 2 (AHA), among others, that intake of SSB and sugars be substantially reduced. The importance of the authors — findings — and therefore their support of the AHA initiative — is considerably undermined by several critical shortcomings.
First, the BP increases associated with incremental increases in SSB or sugar intake shown in author Table 1, though statistically reportable, were not particularly concerning. BP ranges for the highest SSB consumers (>1 serving/d) were 121.1 to 123.9 and 74.5-76.5 mm Hg for systolic and diastolic pressures, respectively. These ranges are very close to the “optimal” (≤120 and ≤80 mm Hg), well below the ‘high-normal’ (≥130 and ≥85 mm Hg) and far below the ‘high’ (≥130 and ≥85 mm Hg) BP categories established in co-author Stamler’s background paper on the INTERMAP project. 3 It would be exaggeration to interpret them as important risk factors for hypertension.
Second, the authors’ observation that all sugars tested — glucose, sucrose and fructose — associated with BP renders obsolete the need to hypothesize a unique link between fructose, uric acid and hypertension (author references 38 and 39). Glucose and sucrose simply do not conform and the hypothesis is biochemically untenable.
And finally, the first two oversights are made moot by the third: SSB, diet beverage and sugars consumption is dramatically different today than in the 1996-1999 period when INTERMAP data were collected. Use of high fructose corn syrup (the principal sweetener used in U.S. SSB) and total sugars have been in decline since 1999; 4 it should be no surprise that case sales of SSB have followed suit. 5 The associations reported by Brown et al. are thus outdated and of little value in guiding contemporary public health policy.
Americans have essentially been doing what AHA is recommending — drinking less SSB and eating less sugar — for the past 12 years, with little effect, apparently, on rising rates of hypertension. Brown et al. clearly showed in this study that increasing SSB or sugars intake had little meaningful impact on BP. It is noteworthy, however, that the authors observed no difference between glucose and fructose associations with BP.
While Brown et al. did little to advance AHA recommendations to reduce SSB and sugar intake, they did provide needed perspective to counterbalance the current hysteria directed at fructose, high fructose corn syrup, added sugars and SSB. AHA might better serve the public by making dietary recommendations that have a more demonstrable effect on BP.
References
1. Brown IJ, Stamler J, Van Horn L, et al. Sugar-sweetened beverage, sugar intake of individuals, and their blood pressure: international study of macro/micronutrients and blood pressure. Hypertension. 2011;57(4):695-701.
2. Johnson RK, Appel LJ, Brands M, et al. Dietary sugars intake and cardiovascular health: a scientific statement from the American Heart Association. Circulation. Sep 15 2009;120(11):1011-1020
3. Stamler J, Elliott P, Dennis B, et al. INTERMAP: background, aims, design, methods, and descriptive statistics (nondietary). J Hum Hypertens. 2003;17(9):591-608
4. Buzby J, Wells HF. Loss-adjusted per capita availability: Average daily added sugar and sweeteners from the U.S. food supply, adjusted for spoilage and other waste. In: USDA Economic Research Service, ed.
http://www.ers.usda.gov/Data/FoodConsumption, Updated 1 February, 2010.