In the Sunday Series today we bring to you a popular article from our archives where Prof. Dr. Sundeep Mishra writes about low sodium salts and why they should never be recommended as a substitute to regular salt to hypertensive, diabetic, and renal disease patients.

Is salt (sodium chloride) essential for life?

1. Sodium is essential for life. It is needed to transmit nerve impulses, contract and relax muscle fibres (including those in the heart and blood vessels), and maintain a proper fluid balance. Sodium also plays a crucial role in the body’s control of blood pressure and volume.
2. Chloride ions, on the other hand, serve as important electrolytes by regulating blood pH and pressure. Chloride is also a crucial component in the production of stomach acid (HCl).

Humans excrete salt when sweating and in urine and thus must replenish these lost sodium and chloride ions. All animals including humans consume foods that naturally contain some salt; meat and seafood are especially rich in it.

However, compared to requirement all human diets are deficient to some degree in salt. Thus added table salt is the main source of sodium and chloride ions in the human diet and may thus play a critical role in maintaining health in human beings.

On the other hand, excess salt can also have side effects. It can predispose one to hypertension (at least in salt-sensitive individuals which are ~50% of total population) and worsen congestive heart failure and renal dysfunction. Thus salt restriction can be useful in patients with manifest hypertension and heart failure.

How to limit salt intake?

Salt restriction

Limiting the amount of table salt and avoiding foods rich in natural salt is one option. Thus limiting to 3 tsp/day and avoiding foods rich in salt can be an ideal way. For salt restriction, foods like smoked, cured, salted or canned meat, fish or poultry or other canned food products should be avoided. Some Indian foods like ghujia/sev and achar are also rich in salt.

Top 10 foods rich in salt

• Smoked, cured, salted or canned meat, fish or poultry including bacon, cold cuts, ham, sausages
• Packaged meats, seafood, canned vegetables and dinners
• Soups, salad dressings
• Fast foods like pizza, sandwiches and hamburgers
• Salted nuts, chips, tortilla and bakery products like biscuits
• Instant puddings
• Processed juice
• Sauces including tomato sauce
• Cottage cheese (Paneer) and processed cheese
• Indian foods like pickles/achar, ghujia/sev etc.

Low sodium salts/salt substitutes

1. Sea salt is a salt which is harvested from Sea, ~ 95% of it is sodium chloride but in addition, it contains around 84 other minerals. Aashirwad salt is one commercially available salt.
2. Table salt or refined salt is sea salt that has been dried at extremely hot temperatures. Its sodium composition is similar to sea salt although the process scrubs off a lot of the minerals it can be fortified with iodine. Many brands are commercially available Tata salt, Annapurna salt, Sundar Health salt, Keya salt etc.
3. Rock salt/Himalayan pink salt is just a marketing term. It’s really just sea salt harvested from a salt mine. in Pakistan, it is harvested some 300 miles from the Himalayas and it is called Himalayan pink salt. Its composition is similar to any sea salt but the colour is pink because of iron oxide it contains.
4. Himalayan black salt (Sendha Namak) is not a full-spectrum salt but rather a condiment. Blocks of salt undergo a process that involves heating and the addition of spices. The salt blocks get blackened as a result of prolonged heating, which, transforms the chemical state of the minerals and the addition of the spices give black salt its egg-y flavour. The block is then ground and the result is the pink powder with black specks. Organic Tattva salt, Puro rock salt, Urban Platter Pink Himalayan rock salt are some examples.
5. Low sodium salts are commercially available salts which are marketed as low sodium salt, but many of them are high in potassium instead. Hence, many patients who are asked to restrict sodium and some health conscious individuals on their own are unknowingly taking these salt substitutes with high potassium content. However, not only are these salts expensive but they could be at higher risk in patients with diabetes mellitus, cardiac diseases and particularly renal disease where they could lead to hyperkalemia secondary to the use of salt substitutes which in turn could increase the need of dialysis in renal patients or worse lead to asystole in cardiac patients who are already on drugs like ACE-Inhibitors and ARBs or potassium sparing diuretics. Thus in no case should a person use low sodium salts without proper advice. Saffola salt plus, Tata Lite, LONA and LoSalt are some of the examples of this type of salt available in India.

Composition and the approximate cost of various salts

Conclusion

Normal salt intake is essential for a healthy life. Patients of hypertension or heart failure may require a reduction in sodium consumption, The best way to achieve this is by salt restriction, however, use of low sodium salts can be dangerous in diabetics, kidney patients and cardiac patients on ACE-Inhibitors or ARBs or potassium sparing diuretics because most of them have added potassium which can cause hyperkalemia.

Disclaimer- The views and opinions expressed in this article are those of the author's and do not necessarily reflect the official policy or position of M3 India.

The writer, Dr. Sundeep Mishra is a Professor of Cardiology.

This article was originally published on 13.02.19