Newscientist have an article about a potential drug which may be able to reduce the amount of sodium absorbed from food (http://www.newscientist.com/article/dn25229-saltbuster-drug-cuts-sodium-absorbed-from-food.html#.UydRgqh_tGY). The drug, known as Tenapanor – also called AZD1722 and RDX5791 – is being investigated for use in end stage renal disease.
It works by inhibiting a molecule in cells in the intestinal wall that transports sodium from the small intestine into the blood stream. In the studies so far, “the drug cut sodium levels in urine…by up to a third,” and increased the amount in faeces by a similar amount. As the sodium levels in urine is a surrogate outcome (i.e. it should give an indication of effectiveness but not necessarily) larger and longer term studies need to be done to confirm if the drug is actually effective at cutting sodium levels.
Theoretically as the drug “works solely within the bowel and isn’t absorbed,” it should affect other body systems but again that needs to be proved in clinical trials.
Of course, the easiest and most foolproof way to cut salt absorption would be to change your diet to reduce your intake to begin with.
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