Eating too much sodium can contribute to high blood pressure in adults. Is a salty diet as dangerous for kids?
In a study published in the journal Pediatrics, researchers at the Centers for Disease Control and Prevention (CDC) say that young children are consuming as much salt as adults, putting them at a similarly increased risk of developing hypertension, a risk factor for heart disease and early death. The high blood pressure risk may greatest among the 37% of American kids who are considered either overweight or obese, the study found.
The scientists reviewed diet and blood pressure data on 6,235 children aged 8 to 18 years who participated in the large government-funded National Health and Nutrition Examination Survey between 2003 and 2008. The children came to mobile sites where trained researchers asked them detailed questions about what they had eaten in the previous 24 hours. The children also had their blood pressure measured three separate times to ensure consistent readings.
On average, the participants ate about 3,387 mg of sodium a day — about the same as adults. (Current dietary guidelines recommend that children and adults consume no more than 2,300 mg a day.) Older children tended to consume more salt than younger children. And the more salt the children ate, the higher their blood pressure readings were. Children with the highest sodium intake were twice as likely to have pre-hypertension or hypertension than those who consumed the least salt. Further, children who consumed the most salt and were also overweight or obese had more than three times the risk of high blood pressure, compared with the lowest salt consumption group.
That means that the combined effect of both excess sodium and excess weight has a magnified effect on blood pressure than either would alone, says the study’s lead author Quanhe Yang, a senior scientist in the division of heart disease and stroke prevention at the CDC. And since hypertension is a major risk factor for heart disease and stroke in adulthood, that suggests that a generation of children may be more vulnerable to these conditions than ever before.
Previous studies have linked rising sodium intake among children and higher blood pressure, but none had factored in the effect of weight on this relationship. Understanding how both sodium and excess weight can influence blood pressure is critical, says Yang, given that more than a third of U.S. children are overweight or obese.
The good news, however, is that cutting salt intake among kids may have a profound effect on their blood pressure, and lead to greater drops in the risk of hypertension than either weight loss or sodium restriction alone. “If we could reduce sodium consumption, that will achieve more than just the expected reduction in hypertension cases because of the synergistic effect,” he says.
Yang’s study shows that the average American child is exceeding the daily recommended sodium intake by more than 1,000 mg. So even if they don’t already have hypertension, youngsters today are at greater risk of developing high blood pressure as they become adults. Recognizing that salt can start affecting blood pressure from a young age could refocus public health efforts to reduce sodium intake among kids as well as adults, he says, and hopefully have a broad effect on controlling blood pressure in the population as a whole.
“If we reduce salt intake beginning in childhood, the effect is going to track through society, and probably translate to a significant change in overall blood pressure both now and in the future,” he says.