Sept. 17, 2012 -- Eating a diet that's high in sodium has been linked in numerous studies to higher blood pressure in adults. Now, new research from the CDC suggests the same link in children and teens.
The investigation found that the more sodium children and teenagers ate, the higher their risk for developing high blood pressure, especially if they were overweight or obese.
Average sodium intake among the children and teens was as high as that of adults. Most sodium is found in processed or packaged foods and restaurant food, not from salt.
CDC nutritional epidemiologist Elena V. Kuklina, MD, who co-authored the study, says high blood pressure is increasingly common among children in the U.S., and high sodium in the diet may be a major contributor.
The average daily intake of sodium among the children and teens in the study was 3,400 mg, the equivalent of just under 2 teaspoons of salt.
That is more than double the daily maximum of 1,500 mg of sodium that the American Heart Association has set as a goal for children and adults.
“We clearly need to reduce sodium intake at the population level,” Kuklina says. “We can do this by eating more fruits and vegetables and less processed foods.”
Kids, Salt, and Blood Pressure
But in a written statement, Morton Satin, who is vice present of science and research for the salt industry trade group the Salt Institute, calls the research "pseudo-science."
The study included 6,235 children and teens who were participants in a larger health study. As part of the study, they were asked to recall all the foods they ate over a 24-hour period.
Just over a third (37%) were overweight or obese, and 15% had either high blood pressure or blood pressure that was above normal but not yet at the level of high blood pressure.
Among kids and teens who were overweight or obese, every 1,000-mg increase in sodium intake per day nearly doubled their risk for high blood pressure or pre-high blood pressure.
Overweight and obese kids and teens who ate the most sodium were 3.5 times as likely to have high blood pressure as overweight and obese kids and teens who ate the least sodium.
Salt Bigger Problem for Overweight Kids
Pediatric cardiologist Stephen R. Daniels, MD, PhD, of the University of Colorado School of Medicine, says the finding that overweight kids may be the most at risk has public health implications.
Daniels, who is a spokesman for the American Heart Association, says he is seeing more and more kids with high blood pressure in his practice.
“When you eat more calories, as kids who are overweight tend to do, you are almost certainly eating more salt,” he says. “This study tells us that sodium intake may be a bigger issue for kids who are overweight.”
Most of the sodium in the diets of kids and teens comes from processed foods, fast-food meals, and school lunches.
An earlier CDC study found that the typical school lunch contains 1,442 mg of sodium.
“Foods that you would never think of, such as breads and many breakfast cereals, are very high in salt,” he says. “If the food industry would get on board and gradually reduce the salt in their products, that could have a huge impact.”
Salt Industry Responds
Satin of the Salt Institute notes that findings from research like the CDC study that rely on participants to recall what they ate are widely viewed as unreliable, or as previously mentioned, what he calls “pseudo science.”
He adds that other aspects of the diets and lifestyles of overweight and obese children, such as eating too many calories or getting too little exercise, may have led to their high blood pressure.
The study will be published online today and will appear in the October issue of the American Heart Association journal Pediatrics.