A few years ago, a large study of more than 150,000 women helped clear poor, vilified coffee of the suspicion it was contributing to hypertension.
But while that 2005 study found no connection between even many daily cups of coffee and high blood pressure, it pointed a finger at another suspect (indeed –one of the usual suspects): It found that soda intake—regular and diet alike—was associated with higher blood pressure.
A new study in Circulation: Journal of the American Heart Association explored the sugary drink-hypertension connection further, and found that by cutting daily consumption of sugary drinks by just one can a day, people can lower their blood pressure significantly.
The study followed 810 pre-hypertensive (people whose blood pressure is elevated but shy of the definition of hypertension) and hypertensive adults, who received diet and exercise advice and behavioral interventions. Blood pressure was measured several times over the 18 months’ study period, and correlated with diet and other factors known to affect hypertension (such as exercise, salt intake and body weight).
Here’s what the study found:
• Reduction of sugary drinks intake is associated with lower blood pressure: After known risk factors of high blood pressure were controlled for, a reduction in sugar-sweetened beverage consumption of one can (12 oz.) per day was associated with a drop of 1.8 mm Hg in systolic pressure and 1.1 mm Hg in diastolic blood pressure over 18 months.• All types of caloric sweeteners are implicated: Change in blood pressure was significantly and positively associated with changes in sugar intake in of any type, including glucose, fructose, sucrose, high fructose corn syrup and combined sugars.
• Caffeine seems to have no effect: There was no significant relationship between change in caffeine consumption and change in blood pressure.
• Diet beverages have no effect: Change in consumption of diet beverages wasn’t associated with lower blood pressure
Doesn’t soda affect blood pressure only through body-weight change?
Sugary drinks are the leading source of added sugar in the US diet, clearly contribute to weight gain, and obesity is a very strong risk factor for hypertension, so the researches set out to see whether reducing soda lowers blood pressure by simply facilitating weight loss.
After adjusting for weight loss the results showed that lowering soda intake was still effective at reducing blood pressure, even among people whose weight was stable.
Is lowering blood pressure a tad going to make a difference?
Hypertension is a major health problem in the US--two thirds of adult Americans have hypertension or pre-hypertension—and hypertension is an established risk factor for heart disease, stroke, kidney disease and early death.
According to the authors, led by Dr. Chen, the public health benefits of reducing soda intake could be significant:
“In view of the direct, progressive relationship of BP (blood pressure) with cardiovascular disease, even small reductions in BP are projected to have substantial health benefits. For example, it has been estimated that a 3-mm Hg reduction in SBP (systolic blood pressure) should reduce stroke mortality by 8% and coronary heart disease mortality by 5%. Such reductions in SBP would be anticipated by reducing SSB (sugar-sweetened beverages) consumption by an average of 2 servings per day. Currently, the average intake of SSB is 2.3 servings per day for US adults. In our study, one third of participants reduced SSB consumption on average of 1.3 servings per day over the 18 months and had an average of 1.5 mm Hg more reduction in SBP compared with participants who did not change their SSB consumption, suggesting that such reduction in SSB consumption should be achievable and could be beneficial.”
Rounding up the usual suspect
We already know that sugary drinks contribute greatly to (empty) caloric intake (the average American takes in about 300 calories a-day in sugary drinks), and that their consumption has been driving the obesity epidemic, with all of its consequences. But in case anyone needed any more proof that it’s time to drop—or at least moderate—our soda habit, this study implicates sugary drinks with yet another health problem—hypertension, and it’s not the first study to do so.
The accumulated evidence against sugary drinks is vast and continues to grow, and soda sales are slowly going down. But what stands in the way of real and sweeping behavioral change regarding soda are two things: soft drinks’ remarkably ingenious and ever-present marketing and advertizing, and their equally remarkable low price. Attempts to change pricing through a soda tax are meeting a bold and no-expense-will-be-spared fight from the beverage industry—one that the beverage industry seem to be winning federally and at the state and city level.
This brings us back to the power of information. I hope that awareness of the ill effects of excessive sugary drink intake and simple logic can help people realize that the simplest and easiest first step towards better nutrition, less weight gain and better health is to give up some—or all—sugary drinks.
Dr. Ayala
Full disclosure: I’m vice president of product development for Herbal Water, where we make organic herb-infused waters that have zero calories and no sugar or artificial ingredients. I’m also a pediatrician and have been promoting good nutrition and healthy lifesyle for many years.
Reposted as part of Food Renegate's Fight Back Fridays--go join the food fight!