By Lisa Rapaport

(Reuters Health) – Declines in salt consumption in England have slowed since a 2011 shift in government policy gave greater freedom to the food industry to set and monitor targets for curbing salt intake, a new study suggests.

As a result, researchers estimate that more Britons have developed heart disease or gastric cancer than would have been the case under the stricter old policy.

Between 2003 and 2010, average salt intake was falling annually by 0.20 grams a day in men and 0.12 grams a day in women, the study found. But progress slowed from 2011 to 2014, when average annual salt intake dropped by just 0.11 grams a day in men and 0.07 grams a day in women.

“The old system set independent targets for salt reduction and monitored these,” said Anthony Laverty, lead author of the study and a public health researcher at Imperial College London. “There was incentive for the food industry to change foods to have less salt in them, alongside some public awareness campaigns and bringing in food labeling.”

But after 2011, “the industry was not under the same amount of scrutiny and their efforts to reduce salt in foods seems to have waned,” Laverty said by email.

Dietary salt can damage the stomach lining, which over time can sometimes lead to gastric cancer, previous research has found. Too much salt is also linked to high blood pressure, a major risk factor for cardiovascular disease, heart attacks and strokes.

Using computer simulations, the researchers estimated how the change in salt policy influenced the patterns of salt-related disease in the population. From 2011 to 2018, the smaller yearly reductions in sodium intake may have been responsible for approximately 9,000 additional cases of cardiovascular disease and 1,500 more cases of gastric cancer than would have occurred under the previous salt policy, the study team reports in the Journal of Epidemiology & Community Health.

If the current policy remains in place, it may cause an additional 26,000 cases of cardiovascular disease and 3,800 cases of gastric cancer between 2019 and 2025, researchers estimate.

These extra cases of cardiovascular disease and cancer added up to 160 million British pounds ($199.89 million) in additional healthcare costs and lost productivity between 2011 and 2018, the researchers calculate. And if the current policy continues, the added health costs and lost productivity will exceed 1 billion pounds by 2025, they estimate.

Adults should consume no more than about 2,000 milligrams of sodium per day, which is the amount found in around 5 grams or one teaspoon of salt, according to the World Health Organization (WHO).

Men and women in the UK consume much more salt than they should: an average of 9.1 grams a day for men and 6.7 grams a day for women as of 2014, the study team notes.

Sodium is found not only in table salt, but in a variety of foods such as bread, milk, eggs, meat, and shellfish as well as processed items like pretzels, popcorn, soy sauce and bouillon or stock cubes.

The study wasn’t designed to prove that the slowdown in yearly reductions in salt consumption caused additional cases of disease. The researchers also examined trends for the whole population and didn’t look at health outcomes for individuals based on their specific levels of salt consumption.

It’s also not clear whether salt intake would have continued to decline at the pre-2011 pace in the absence of a policy shift in the UK, said Dr. Dariush Mozaffarian of the Friedman School of Nutrition Science & Policy at Tufts University.

“Many of the ‘easier’ wins in sodium reduction had already been leveraged by 2012: lowering sodium in certain products, by modest amounts, is technically much easier than larger reductions or reductions in other types of products,” Mozaffarian, who wasn’t involved in the study, said by email. “Achieving further linear reductions at the same pace would be unlikely.”

Both the current and the previous salt policies in the UK did lead to reductions in salt intake, suggesting that more than one approach may help, Mozaffarian added.

SOURCE: Journal of Epidemiology and Community Health, online July 18, 2019.