"These findings highlight both the tremendous disease burdens caused by sodium but also the incredible opportunities for prevention," according to Mozaffarian.
Mozaffarian urged global public health efforts rather than relying on individuals to control intake of so pervasive an element.
"Our results should inspire both food industry and policymakers to take rapid and decisive actions to reduce sodium in the food supply," he said. "If voluntary agreements are not enough, taxation or restrictions on amounts of sodium should be implemented."
"Sodium reductions have been shown to be one of the most cost saving strategies in reducing the burden of noncommunicable disease," added co-author Saman Fahimi, MD, MPhil, also of Harvard, who presented part of the data at the conference.
The group systematically reviewed published and unpublished estimates from 247 surveys of sodium intake done among adults from 2007 through 2012 as part of the Global Burden of Diseases study.
A little over half of the data came from objective 24-hour urinary sodium measurements; the rest was gleaned from diet-based surveys.
Altogether, the analysis contained direct data for 66 countries and 74% of the world population. Extensive imputation modeling with country-level and survey-level covariates extended the analysis to 187 countries, covering nearly the entire globe.
Only six nations didn't shake out with an average sodium intake exceeding the WHO limit of 2,000 mg a day; only Kenya had a national average that would meet the AHA threshold of 1,500 mg per day.
Notably, 119 countries -- representing 88% of adults worldwide -- averaged more than 3,000 mg a day.
The saltiest regions were:
- Central Asia, with an average of 5,500 mg sodium per day
- High-income countries in the Asia-Pacific area, averaging 5,000 mg per day
- East Asia, with an average of 4,800 mg per day
- East sub-Saharan Africa came in lowest at a daily average sodium intake of 2,200 mg, followed by central sub-Saharan Africa at 2,400 mg and Oceania at 2,500 mg.
- American adults averaged about 3,600 mg a day.
A further analysis reported by Mozaffarian at the meeting broke down the impact of these salty excesses based on clinical results from meta-analysis of 107 randomized controlled trials.
The number of cardiovascular deaths attributable to sodium intake greater than 1,000 mg per day in 2010 was estimated at 2.30 million -- 42% from coronary heart disease and 41% from stroke.
The heavier burden fell on less affluent nations, with 84% of deaths in low and middle-income countries.
The most affected nations in terms of mortality attributed to high sodium intake were:
- Ukraine, with 2,109 deaths per million adult population
- Russia, with 1,803 deaths per million
- Egypt, with 836 deaths per million
The highest proportion of cardiovascular disease deaths attributed to salty diets were in the Philippines, Myanmar, and China, all at 20%.
Decreasing sodium intake on a population level presents different challenges for richer and poorer nations, Mozaffarian told MedPage Today.
"Some lower-income countries may face less opposition from industry, lobbyists, and even the public to take action," he said. "Higher-income countries have the resources for immediate action, but the power of industry to influence decision makers is very strong."
Signs that yopu May have too Much Salt in your Diet
- Bloating. Salt can cause water retention.
- Excessive Thirst. Generally people who are consuming too much salt tend to also be more thirsty.
- High blood pressure.
- Hypernatremia. Hypernatremia occurs when a person becomes dehydrated and the kidneys cannot cope with excess salt in the bloodstream. This is a serious condition that can lead to brain damage. Some of the symptoms include irritability, muscle cramps, confusion, depression and vomiting.
Salt should not be cut out of a diet completely, but the vast majority of people should try to reduce their current salt intake.