A new study which includes data from 187 countries has concluded that there were approximately 1.65 million deaths in 2010 that can be attributed to cardiovascular problems associated with eating too much salt. Too much salt exceeds 2,000 milligrams or 2.0 grams per day. About 667,000 of these deaths were considered to be premature in that death occurred before the person was 70 years old. The study results were published in the New England Journal of Medicine.
An international research team carried out the study. Dr. Dariush Mozaffarian of the School of Public Health at Harvard University was the lead scientist. The researchers found that the average global sodium consumption per day was about 3.95 grams, which is high since the World Health Organization (WHO) recommends consuming no more than 2.0 grams per day. Central Asia was found to have the highest intake of salt per day (5.51 grams) and sub-Saharan Africa was found to have the lowest intake at 2.18 grams per day. The cases of mortality were derived from the 2010 Global Burden of Diseases Nutrition and Chronic Diseases Expert group study.
The conclusions of the study were also based on a meta-review of previously published controlled intervention studies. A meta-review analyzes combined data from studies that had similar methodology. The combined data allows for greater statistical power. This research project was said to be a “herculean effort” in an editorial published in The New England Journal of Medicine.
The association between a high salt diet and cardiovascular disorder-related deaths is that high salt intake has been linked to high blood pressure, and high blood pressure has been said to lead to cardiovascular problems. For decades, many have recommended lowering salt intake to lower high blood pressure. The idea is that this would lower risk for heart attacks, strokes and other vascular complications.
A point of contention regarding this link, however, raises questions that have not been fully answered. The question remains whether high salt intake causes high blood pressure, or whether it is a problem because it exacerbates high blood pressure that already exists. Another point to consider is the role of potassium, which may counter the negative effects of too much sodium.
There are plenty of warnings in the media and literature provided by medical care workers that say that only worrying about pouring salt on food from a salt shaker is not enough. Pre-packaged food and foods prepared in restaurants often have high levels of sodium. Moreover, certain foods naturally contain high sodium levels and this should be considered as well.
An interesting note here is, in the same issue of The New England Journal of Medicine, two other studies concluded that ingesting too little sodium per day also has negative effects on health. Moreover, an editorial was published in the same issue of the journal discussing the conflicting studies. When highly regarded scientists publish their results in highly regarded journals, and their conclusions conflict, it can be difficult for the general public to know what to do. To eat more salt or less salt is the question all must face and decide for themselves.
By Margaret Lutze
See Related GLV article: “Too Little Salt Linked to Cardiovascular Problems, According to Study”