The finding, published in JAMA Internal Medicine, established that although overall sodium levels of processed foods decreased from 2005 to 2011, the decrease was just 3.5%. Restaurants did not perform well at all, documenting that sodium levels actually rose by 2.6% over the same time frame.
The results suggest that food manufacturers have not made much progress between 2005 and 2011 in decreasing sodium levels in restaurant and packaged foods. The authors suggest that now significant action is required by the Food and Drug Administration in order to decrease sodium content of restaurant and packaged foods. They believe this goal can be achieved slowly over a 10-year period.
Not only are sodium levels high, but a separate report also published in JAMA Internal Medicine this week revealed that small and independent restaurants are serving extremely high calorie meals. These meals reportedly contain three times the amount of energy an average adult should consume in one meal.
CSPI executive director Michael F. Jacobson, study author, said:
"The strategy of relying on the food industry to voluntarily reduce sodium has proven to be a public health disaster. Inaction on the part of industry and the federal government is condemning too many Americans to entirely preventable heart attacks, strokes, and deaths each year."
Consumption Of Sodium Needs to ChangeExcess intake of sodium is a significant cause of hypertension - a major risk factor for stroke and heart disease. The greater the intake level, the more elevated a person's risk is for hypertension. Approximately 80% of the sodium digested by Americans is added by restaurants and food manufacturers.
Researchers from Brigham and Women's Hospital, Harvard Medical School and the Harvard School of Public Health, found that in 2010, high salt intake was linked to 2.3 million deaths around the world. Most of these deaths occurred in low and middle-income nations.
The average salt content in the 12 types of barbecue sauces analyzed by CSPI rose by 6.3%, while the average salt content in 11 types of Caesar's salad dressings rose by 3.7%, and the average salt in 7 types of 100% whole wheat bread rose by 3.6%.
On the other hand, fresh or frozen pork, canned diced tomatoes, vegetable soup, canned white tuna, and sliced turkey breast all documented average decreases in sodium of over 20%.
The researchers suggest that currently per-capita, sodium intake is approximately 3,300 milligrams per day, but could be nearly 3,800 mg per day when adjusted for other factors.
The majority of the population - a group made up of African Americans, middle-aged or older people of any ethnicity, and also people with diabetes, kidney disease, or high blood pressure - are advised to restrict their salt intake to 1,500 mg per day.
The American Heart Association recommends the same restrictions to any person over the age of two. Scientists say that this is next to impossible without significant changes by the food industry.
CSPI found that salt levels differed significantly among brands with similar products. For instance, one tomato paste contained over 5 times as much sodium as the brand with the least, and ounce-for-ounce, McDonald's Quarter Pounder with Cheese had 34% more salt than Burger King's Original Whopper with Cheese.
Research conducted by UCLA found that Subway is not a much healthier option than McDonald's for teenagers and young adults. They found that consumers eat more-or-less the same number of calories at both restaurants.
Although the study's sample of 480 foods seems extensive, it is still a small percentage of the thousands of foods in restaurants and grocery stores, the authors pointed out.
Stephen Havas of the Northwestern University Feinberg School of Medicine, and co-author of the study, said:
"The current high levels of sodium in packaged and restaurant foods, if not reduced, will likely cause at least one million deaths and $100 billion in health-care costs in the coming decade. Action by the FDA requiring the food industry to lower sodium in our food supply is long overdue and should begin without further delay. The Obama administration should take action forthwith."