Added sugar may be the mystery ingredient causing hypertension, researchers say
Blood pressure has been rising in the United States for more than 100 years. At the turn of the last century, about 5% to 10% of American adults were diagnosed with hypertension; today, the figure is about 30%. Why?
Perhaps it’s because there’s so much more added sugar in our diets now than there was a century ago. Studies have linked consumption of fructose – the ingredient that makes up 50% of table sugar and 55% of high-fructose corn syrup – to high blood pressure in rats. But in people, the link has been elusive.
Researchers from the University of Colorado Denver checked to see whether added sugar intake was linked to blood pressure among the thousands of representative Americans who participated in the National Health and Nutrition Examination Survey between 2003 and 2006.
By comparing the diets and systolic blood pressure (the top number in a blood pressure reading) of all the volunteers, they found that those who ate and drank more fructose from added sugars (as opposed to healthy sources like fresh fruit) had higher blood pressure than those who didn’t. They also discovered that volunteers with higher blood pressure tended to have larger waistlines.
Overall, those who consumed at least 74 grams of fructose per day from added sugars were more likely to be hypertensive. Compared with a healthy blood pressure of 120/80 mmHg, those with diets high in added sugar were 77% more likely to have blood pressure of 160/100 or greater. (The NIH considers anything over 140/90 to be high blood pressure.) The association between added sugars and blood pressure held up even when controlling for other factors, such as total calories consumed, physical activity, other health problems and consumption of salt, alcohol and carbohydrates.
So, how much junk food do you have to eat to hit 74 grams of fructose? Drinking 2½ 20-ounce bottles of Coke would do it. Among the volunteers in the NHANES study, half consumed more than 74 grams of fructose from added sugars each day.
Why worry about high blood pressure? It’s a risk factor for a whole bunch of health problems you’d probably rather avoid, including coronary artery disease, congestive heart failure, stroke and chronic kidney disease. The World Health Organization estimates that hypertension causes 7.1 million deaths each year.
The good news, the researchers said, is that it’s easy to reduce your risk. Simply cut back on foods with lots of added sugar.
The findings were published online Thursday by the Journal of the American Society of Nephrology.
-- Karen Kaplan
Photo: Sugary foods aren’t just bad for your waistline, they may threaten your blood pressure too. Credit: Anne Cusack / Los Angeles Times