The fourth edition of a Center for Science in the Public Interest (CSPI) survey has reported a 4-percent reduction in sodium across 451 pack- aged and restaurant foods over a 10-year period. Titled “Salt Assault: Brand-name Comparisons of Processed Foods,” the report claims that, on average, surveyed items reduced their sodium content by 41 milligrams per 100 grams of product.

The consumer watchdog notes, however, that many products still have room to make additional reductions. Citing “dramatic variations in sodium content across different brands of a given food,” the report singles out products in the canned diced tomato, whole wheat bread and ketchup categories—among others—for further improvement. In particular, CSPI urges the U.S. Food and Drug Administration (FDA) and Department of Agriculture to not only set mandatory sodium limits for processed and restaurant foods, but require warning labels on those that are high in sodium.

“For 40 years, the food industry has offered voluntary action to reduce sodium in packaged foods, and for 40 years, the FDA has obediently observed from the sidelines,” said CSPI President Michael Jacobson in an April 5, 2016, press release. “This has resulted in an uneven playing field for industry with some companies stepping up and others doing little. Excess sodium in our foods is prematurely disabling or killing tens of thousands of Americans each year.”