Salty deaths

Walk into any food emporium these days and what is the one food product that will be found just about anywhere regardless of cuisine, regardless of price, and regardless of the implications? The answer of course is “salt”. This not so humble seasoning is offered on every restaurant table, is pre-added to many meals, and is insinuated into a large number of processed foods. According to two new studies just released the pervasive nature of salt is not good news for our individual and collective health.

Salt of course, is not new.

Salt was used as a part of Egyptian religious offerings and was a valuable trade commodity for the Phoenicians. The word “salary” comes from the fact that salt was once legal currency in many parts of the world. Salt was used as a seasoning and as a means of preserving food. Later, salt was used in such processes as tanning, dyeing, and bleaching.

Yet despite its historic popularity salt has never been used with the frequency and quantity that it is today. More than 210 million tonnes of salt are produced every year and 75 per cent of the salt you consume is in processed food. Chemically salt is just sodium chloride, with the formula NaCL (Na = sodium, CL = chlorine). Salt is about 40 per cent sodium and 60 per cent chlorine. It sounds innocuous enough but it is a real health concern.

In one new study researchers analysed data from 247 surveys of salt intake taken between 1990 and 2010 as part of the Global Burden of Diseases Study (an international effort involving 303 institutions from 50 countries). Since we know that sodium increases blood pressure the researchers wanted to see whether too much salt (defined as more than 1000mg a day) would increase risk of heart disease. In fact they found that in 2010 2.3 million premature deaths (before age 69) were due to excessive salt intake.

If the thought that salt can kill you is not enough there is the possibility raised by another study that it can make your life quite difficult as well. This research found that salt increases production of a type of immune cell called the TH17 cell. These cells help protect against foreign invaders but too many of them can lead to autoimmune disease like multiple sclerosis, rheumatoid arthritis, and psoriasis. Indeed, treatments for some of these autoimmune conditions involve manipulating TH17 function.

So if you want to live longer and live better it might be an idea to cut back on salt consumption. That might not be the best news you’ve heard today, but you would be wise not to take it with a grain salt.