UCSF.edu – Cutting back on salt in teenagers’ diets by as little as one-half teaspoon, or three grams, a day, could reduce the number of young adults with high blood pressure by 44 to 63 percent, according to new research presented Sunday, November 14, 2010 at the American Heart Association’s Scientific Sessions 2010 meeting in Chicago.

The findings indicate that the food industry and those who regulate it could substantially improve the nation’s health through even small reductions in the amount of salt in processed foods, which account for the majority of salt consumed in this country.

“The U.S. diet is already high in salt, and adolescents consume more salt – more than 9 grams (3,800 milligrams of sodium) – than any other age group,” said presenter Kirsten Bibbins-Domingo, PhD, MD, UCSF associate professor of medicine and epidemiology.  The American Heart Association, who funded this study, recommends no more than 1,500 milligrams of sodium a day for most Americans.

“It’s clear that we need to lower salt intake, but individuals find it hard to make substantial cuts because most salt comes from processed foods, not from the salt shaker,” said Bibbins-Domingo, who co-directs the UCSF Center for Vulnerable Populations at San Francisco General Hospital.  “Reducing the amount of salt that is already added to the food that we eat could mean that teenagers live many more years free of hypertension.”

“Fast food and snack foods are major contributors to salt intake among teens, and reducing intake of these food items can have an important health benefit for teens during their teenage years and as they become young and middle age adults,” she said. About 80 percent of salt comes from processed or prepared foods – 35 percent of that in cereals, breads and pastries.

Pizza is the biggest culprit of salt for teens according to data from the National Center for Health Statistics.

By lowering dietary salt by three grams per day, the researchers projected the following benefits for healthcare in the United States over time as teenagers reach age 50:

• 7 to 12 percent reduction in coronary heart disease (120,000 to 210,000)
• 8 to 14 percent reduction in heart attacks (36,000 to 64,000)
• 5 to  8 percent reduction in stroke (16,000 to 28,000)
• 5 to  9 percent reduction in death from any cause (69,000 to 120,000)

Salt consumption among Americans has risen by 50 percent since the 1970s, according to the American Heart Association, and blood pressure has risen by nearly the same amount – despite extensive evidence linking salt intake to high blood pressure (hypertension) and heart disease.

In addition to its independent benefits on blood pressure, reducing salt intake can enhance the effects of most anti-hypertensive (blood pressure lowering) agents and reduce complications associated with diabetes, obesity and kidney disease, the researchers added.

According to federal government data, the average teenage boy consumes more than 10 grams of salt (4,000 mg sodium) daily.  Most health organizations recommend far lower targets – no more than 5.8 grams of salt per day (2,300 mg sodium) and less than 3.8 grams (1,500 mg sodium) is optimal.  Each gram of salt contains 0.4 grams of sodium.

Study Highlights:

• Small decreases in salt consumption among teens could prevent many cases of high blood pressure, heart disease and stroke in adulthood.
• Processed foods and fast foods, pose high salt hazards to families and teens.
• Researchers say food manufacturers should continue to reduce salt levels in their products.