In this prospective study of 810 men and women with prehypertension and stage I hypertension, there was a positive association between change in SSB consumption and change in BP. After controlling for potential confounders, an average reduction in SSB intake by 1 serving (12 fl oz) per day was associated with a 1.8 mmHg (95% CI: 1.2 to 2.4 mmHg) reduction in SBP and 1.1 mmHg (95% CI: 0.7 to 1.5 mmHg) reduction in DBP over 18 months. This association was partially mediated through weight change. Specifically, after controlling for weight change over the same period, the association between SSB intake and BP was attenuated by approximately 61% (0.7 mmHg/per serving for SBP and 0.4 mmHg/serving for DBP), but still statistically significant (P < 0.05, each), suggesting that reducing SSB intake has a BP lowering effect which is independent of weight loss. We also observed significant, positive associations of BP with change in consumption of sugars (glucose, fructose, sucrose, and combined sugar), but not with change in consumption of caffeine. No association was found for diet beverage consumption and BP. These data suggest that sugars may be the nutrients in SSB that contribute to the observed association between SSB and BP.
Our results are supported by data from two large prospective studies and one cross-sectional study suggesting a positive association between SSB consumption and the risk of hypertension. Data from the Nurses' Health Study17
showed a strong positive association between cola beverage intake and hypertension risk (P for trend < 0.001). Additionally, an analysis of data from the Framingham Offspring Study15
also found that consumption of soft drinks (regular and diet soda combined) was associated with an increased risk of high BP, although not statistically significant. In addition, cross-sectional findings from NHANES (1999–2004) data among adolescents (12–18 years) indicated a positive association between SSB consumption and directly measured BP16
Our results provide additional evidence supporting a relationship between higher SSB consumption and elevated BP. First, the data show that SSB affects BP in part via mechanisms that are independent of weight change. Second, the relationship is evident in both non-hypertensive and hypertensive, suggesting reduced SSB should have a role in both preventing and treating hypertension. In contrast with the above-mentioned two studies which observed an increased hypertension risk associated with both SSB and diet soft drinks15, 17
, we found no association between diet beverages and BP in present study ().
The mechanism by which higher intake of SSB may increase BP is uncertain. It is well documented that ingestion of caffeine has an acute pressor effect22, 23
. However, tolerance to the caffeine-induced pressor effect develops within days23
. We found no association between 18-month change in caffeine intake and BP in present study. Studies in a variety of animal models, including rats, dogs, and primates11–14
, have shown that diets high in glucose, fructose, or sucrose can induce hypertension. There are few similar studies in humans, and one study has reported that a diet high in sucrose, consumed for 6 weeks, causes a significant elevation in BP24
A possible mechanism for the pressor effect of sugars may be enhanced sympathetic nervous system activity. An acute increase in catecholamine secretion has been shown after ingestion of sugar during euglycemic clamp studies25
. Another mechanism may be a reduction in sodium excretion, as documented in animal and human studies26
. Recent evidence suggests that fructose consumption might increase BP by raising serum uric acid16, 27
, which can decrease endothelial nitric oxide and/or activate the renin-angiotensin system28
Our study has several strengths. First, both diet and BP were measured frequently by trained, certified staff. Second, our study had precise, objective measurements of potential confounders including weight, urinary sodium excretion, physical activity, fitness, and other covariates. Third, the follow-up rate was high and missing data were uncommon. Furthermore, the BP status of our study population is comparable to the BP of two-thirds of the U.S. population. Our study is limited in that it included few Hispanics and Asians. Additionally, given the observational nature of our study, it cannot prove causality or completely rule out residual confounding. Randomized controlled trials are needed to confirm the observation and to determine whether interventions that target SSB or sugar consumption can lower BP among adults.
Our study has important public health implications. In view of the direct, progressive relationship of BP with CVD, even small reductions in BP are projected to have substantial health benefits. For example, it has been estimated that a 3 mmHg reduction in systolic BP should reduce stroke mortality by 8% and CHD mortality by 5%29
. Such reductions in SBP would be anticipated by reducing SSB consumption by an average of 2 servings per day. Currently, the average intake of SSB is 2.3 servings per day for U.S. adults. In our study, one third of participants reduced SSB consumption on average of 1.3 servings/day over the 18 months and had an average of 1.5 mmHg more reduction in SBP compared with participants who did not change their SSB consumption, suggesting such reduction in SSB consumption should be achievable and could be beneficial.
In summary, findings from this prospective study suggest a positive association between SSB consumption and BP. These findings warrant future studies, particularly randomized controlled trials, to establish the causal relationship.
Consumption of sugar-sweetened beverages (SSB) has increased dramatically in the United States (U.S.). While high SSB consumption has been linked with excess calorie intake and overweight/obesity, SSB may have other adverse effects. In a prospective study of 810 U.S. adults with prehypertension and stage I hypertension, we found that reducing SSB consumption was associated with significant reductions in blood pressures (BP). On average, a reduction in SSB intake of 1 serving/day (12 ounces/day) was associated with a 1.8 mmHg reduction in SBP and 1.1 mmHg reduction in DBP over 18 months. A positive association was also found for dietary sugar intake and BP. No association was found for diet beverage consumption or caffeine intake and BP. These findings have important clinical and public health implications. It has been estimated that a 3 mmHg reduction in SBP should reduce stroke mortality by 8% and CHD mortality by 5%. Such reductions in SBP would be anticipated by reducing SSB consumption by an average of 2 servings per day. Currently, the average intake of SSB is 2.3 servings per day for U.S. adults. National wide, 72 million (35%) U. S. adults have hypertension and another 59 million (29%) have prehypertension. Given the high prevalence of both SSB consumption and hypertension in the U.S. and throughout much of the world, even small reductions in the SSB consumption should have a beneficial public health impact. In conclusion, our data suggest that reducing SSB and sugar consumption may be an important dietary strategy to lower BP.