Put a bunch of 4-year-olds in a room and place two childhood favorites in front of them: salted pretzels and M & Ms. Then tell them to help themselves -- and get out of the way. What they choose may have a lot to do with how much they weighed when they were born.
It also may shed some light on the risk factors for hypertension later in life.
Curious about the links between low birth weight and future risks for heart disease, and between salt and hypertension, researchers began a study to see whether some children are born liking salt more than other children. They tested about 80 children at 2 months, at 6 months, and at 3 to 4 years.
"Given that we know that there's a large literature that suggests that the intake of sodium is related to the risk of hypertension, we wanted to see if there was any link between birth weight and a liking for salt," says Leslie Stein, a researcher with the Monell Chemical Senses Center, an institute in Philadelphia focused on understanding smell, taste and chemical irritation.
By 2 months, smaller babies, or those who had been about 5.5 pounds at birth, liked salt more than their peers born at 8 or 9 pounds. They drank salted water that bigger babies rejected. By age 3 to 4, the children born smaller were choosing pretzels and potato chips while children born larger were picking chocolates and unsalted banana chips, according to Stein's research, published Nov. 23 in an advance online issue of the European Journal of Clinical Nutrition.
"It's a first step in showing there could be a link between birth weight and hypertension later in life," she says.
To understand what health effect, if any, a preference for salty foods might have when the smaller babies grow to be adults means entering science's unresolved salt wars.
Some experts, including those at the National Heart, Lung and Blood Institute, believe that Americans should reduce their salt intake. The American Heart Assn. and the Institute of Medicine recommends no more than about a teaspoon each day to reduce the risk of high blood pressure and heart disease -- a dose exceeded by 95% of American men and 75% of women.
Other experts believe that salt has little bearing on heart disease, and even a drastic reduction in salt does little to bring down high blood pressure.
After at least 30 years of medical studies, the question remains unresolved.
