Friday, December 18, 2009

Is Salt More of a Threat After All?

In reviewing research out of Italy and published in the British Medical Journal BMJ, I began to doubt myself or my recent post.

The research involves the analyses of about 14 different studies that included measure of salt intake and the outcomes of stroke or cardiovascular disease. The studies are not the gold standard type that we like, nor could they really be, but the analyses of them is pretty tight.

The scientists and statisticians found that salt intake, which they measured in grams, is associated with higher risks for both of the above outcomes. Remember from a recent post that the sodium content is 40%, and so when they say 6 g of salt it equals about 2300 mg of sodium. The researchers say that most diets have upwards of 10g of salt per day (WOW) and that 10g a day puts a person at an amplified risk of stroke death and CVD diagnosis. The report I read in Medscape stated that for every additional 3 grams of salt we consume, our risk of heart disease rises by 6 percent.

My big question is this: Does that mean that we have a higher risk of getting hypertension and then the adverse outcomes, or is it regardless of a HTN diagnosis. That is a pretty important question as not everyone who consumes above 6g of salt a day gets or has high blood pressure.

Also I learned in the article by Susan Jeffrey that one of every strokes leads to death where as one in every five cases of heart disease leads to death. I didn't realize that so many strokes resulted in death, however, in some instances it might be the better outcome.

My curiosity did get the better of me, i.e. if the increase in salt led to the stroke or if the increase in salt led to the HTN that then led to the stroke. So I looked up the research myself.

Wow, this stuff can get confusing. I need more education! Anyways, the authors of the study do call it a direct link between intake and stroke or CVD but they also talk about HTN and obesity etc as factors for stroke and heart disease. It was said in the research article that about 62% of strokes ARE in those with HTN and almost 50 % of CVD cases are associated with HTN. Still, the research did find some cases of increase without the diagnosis of high blood pressure which gives weight to efforts for overall reductions in salt intake.

Keep in mind however that the scientists are presenting this data not for individual behavior change but for changes in the food industry that will have population wide effects to save millions of lives.

No comments: