Less salt in teenagers' diet may improve heart health in adulthood

Conducting a sophisticated computer modeling analysis, researchers projected the nationwide health effects of a 3-gram reduction in dietary salt from processed foods consumed by adolescent boys and girls.

Teenagers eat more salt each day -- more than 9 grams (3,800 milligrams of sodium) -- than any other age group, researchers said. The American Heart Association recommends no more than 1,500 milligrams of sodium per day for most Americans.

By reducing the salt teenagers eat each day by 3 grams, researchers projected through modeling a 44 percent to 63 percent (380,000 to 550,000) decrease in the number of hypertensive teenagers and young adults. They estimated a 30 percent to 43 percent decrease (2.7 to 3.9 million) in the number of hypertensives at ages 35 to 50.

"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," said Kirsten Bibbins-Domingo, Ph.D., M.D., lead author of the study and associate professor of medicine and epidemiology at the University of California, San Francisco. "The additional benefit of lowering salt consumption early is that we can hopefully change the expectations of how food should taste, ideally to something slightly less salty."

A one-gram-per-day reduction in salt consumption results in a small drop of systolic blood pressure of 0.8 mm Hg, she said. "Reducing the salt in the teenage diet from an average of 9 grams to 6 grams would get teenage boys and girls to appropriate levels of salt intake."

Measurable health benefits over time as teenagers reach age 50 would include:

• 7 percent to 12 percent reduction in coronary heart disease (120,000 to 210,000)
• 8 percent to14 percent reduction in heart attacks (36,000 to 64,000)
• 5 percent to 8 percent reduction in stroke (16,000 to 28,000)
• 5 percent to 9 percent reduction in death from any cause (69,000 to 120,000)

About 80 percent of salt comes from processed or prepared foods -- 35 percent of that in cereals, breads and pastries.

"The hidden places of salt in our diet are in breads and cereals, canned foods and condiments, and of course fast foods," said Bibbins-Domingo, also co-director of the UCSF Center for Vulnerable Populations. "Most of the salt that we eat is not from our salt shaker, but salt that is already added in food that we eat."

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

Manufacturers should continue to reduce salt in their foods in cooperation with local, state, and federal regulatory agencies, she said. Many major companies have already joined the National Sodium Reduction initiative and have voluntarily agreed to work to lower the salt content that is already added to processed and prepared foods.

Co-authors are: Pamela Coxson, Ph.D.; Tekeshe Mekonnen, M.S.; David Guzman, M.S.; and Lee Goldman, M.D., M.P.H. Author disclosures are on the abstract.

The American Heart Association funded the study.