It’s World Salt Awareness week from 9th to 15th March. This is a week when many organisations, usually public health led advertise that we should be aware of the amount of salt that we eat and the consequences of eating too much. We might be quite conscious of the amount of salt that we shake or grind onto our food on a daily basis, but are we aware of so called ‘hidden’ salt? That is the salt added to foodstuffs such as soups, sauces, bread, biscuits and breakfast cereals. It can be very difficult to know how much hidden salt we are eating if we are not checking labels and weighing out our food – who does that?
Types of salt
Do you buy ‘table salt?’ Or do you like to be a little more sophisticated and buy for example sea salt, rock salt, pink Himalayan salt, salt flakes or some other kind of fancy named salt. Do you think you are buying a healthier salt if it’s from the Himalaya’s? Salt is made up of approx. 40% sodium and 60% chloride, and the crystalline structure of salt as we know it consists of one molecule of sodium surrounded by six of chloride. Many of these different types of salts are largely the same in that they contain between 97-100% sodium chloride, so the effects on the body are the same irrespective of whether you use table salt or sea salt for example. The only difference you find is in your wallet, where you will be paying a lot more for rock salt for example than table salt. It is also worth noting that the larger crystals of rock or sea salt will see you using more sodium chloride than if you were using table salt for example as the table salt has a finer grain so by default you use less.
There are some other types of salts on the market that are worth mentioning. LoSalt® for example is a combination of sodium chloride and potassium chloride, where sodium levels are claimed to be 66% lower than regular table salt, rock salt and sea salt, without a compromise on taste (LoSalt®, 2020).
Some commercial salt products have added iodine. Iodine is a key mineral for healthy functioning of the thyroid gland and most iodine in the diet is obtained from milk (see my previous blog about Iodine). However, it could be argued that added iodine does not reduce the amount of sodium chloride, so it still applies that you should consume no more than a teaspoon of sodium chloride per day.
But our body needs sodium!
Our body requires small amounts of sodium to conduct nerve impulses, contract and relax muscles, and maintain the proper balance of water and minerals (Harvard T. H. Chan, 2020). We require approx. 500 mg of sodium daily, but UK adults are consuming on average 8.1 g salt per day which equates to approx. 3,200 mg of sodium. In the UK it is recommended that we don’t consume more than a teaspoon of salt in total per day (approx. 6 g) (NHS, 2018).
Our body in fact requires more potassium than sodium as it helps control the balance of fluids in the body and helps the heart muscle work properly. We need approx. 3,500 mg of potassium per day, and this should be easy to consume in a healthy balanced diet and in general it is not advisable to take supplements (NHS, 2017). Good food sources include; bananas, broccoli, Brussels sprouts, pulses, nuts and seeds, shellfish, beef, chicken and turkey.
Health consequences of consuming too much salt
According to the British Heart Foundation (BHF), consuming too much salt can increase the risk of developing high blood pressure. High blood pressure increases the risk of developing coronary heart disease (BHF, 2020). High blood pressure rarely has any noticeable symptoms; hence it is important to have it checked on a regular basis. A review of 34 different trials covering 3230 participants found that a modest reduction in salt intake of four or more weeks caused a significant fall in blood pressure in both hypertensive and normotensive individuals, irrespective of sex and ethnic group (He, Li, MacGregor, 2013).
Hidden salt and how to avoid it
Salt as well as a taste enhancer is a stabiliser and a preservative, as bacteria cannot thrive in the presence of high levels of salt, so in some foodstuffs it could be argued that salt is an anti-staler and is functional. However, in the body salt still has the same effect whether it is added for taste or used for preservation, so it’s important to always try to be aware of how much salt we are consuming.
Hidden salt is probably the hardest to track, because it’s contained in many regular foodstuffs and unless we read the labels it’s difficult to keep an eye on how much we are eating. As a Nutritionist there are some simple suggestions I can make to help you to try to keep hidden salt consumption to a minimum. These include, using low salt versions of your normal food products e.g. low salt stock cubes, low salt ketchup, low salt soy sauce, low salt baked beans, low salt soups and sauces, unsalted butter and spreads. You make think that these types of foodstuffs don’t taste very nice, but the manufacturers will try to use other ingredients to compensate the taste such as herbs and spices. You must be aware though that you are not swapping salt for some other ingredient that might be unhealthy such as too much sugar or fat.
Like with sugar you can train your palate to become used to low salt. If you cannot take a hit on reducing salt dramatically all at once, try to slowly reduce its usage, this is possible when you add salt to cooking or on already prepared food. Try to add just a little if you have to. Sometime I feel it’s psychological that you have to shake salt on your food, when most of the time it is unnecessary. Overtime keep reducing the amount you use, eventually you will not be able to eat a lot of salt on your food as your palate will adapt to the lower levels.
Try to avoid or lower the portion sizes of, the following types of foods that will have high levels of hidden salt; processed and cured meats such as bacon, ham and salami, pizza, crisps, snacks and salted nuts, smoked meat and fish, and bread products.
The UK government recognised that hidden salt in food posed a health risk to society so began work on a salt reduction programme that began in the UK in 2004 following advice from the Scientific Advisory Committee on Nutrition (SACN) that recommended population average salt intakes should be reduced to 6 g per day to reduce the risk of high blood pressure and hence cardiovascular disease (Public Health England, 2017). A study that looked into the effects on health of a reduction in salt levels between 2003 and 2011 found that the UK salt reduction programme led to a fall in population blood pressure and thereby stroke and heart disease events and deaths. From the fall in blood pressure that was due to the salt reduction there has been a saving of approximately 18,000 stroke and heart attack events a year, 9,000 of which would have been fatal (He, Pombo-Rodrigues & MacGregor, 2014).
It is clear that we must try to keep our salt consumption to no more than 6 g per day, in order to reduce the risk of developing high blood pressure that can lead onto increased risk of coronary heart disease, stroke and heart attack. Using less salt in cooking and less when shaking onto prepared foods is one way to reduce direct usage of salt, but we must also be aware of hidden salt in processed, pre prepared foodstuffs. Whilst the UK government are pressing ahead with salt reduction targets for food manufacturers, more can still be done and as consumers we should read the label to help choose food that is low in salt. We should also try to cook food from fresh using less salt and avoid foods or lower their portion sizes, that are typically high in salt, as discussed earlier.
BHF (2020). Salt. Accessed online 08 Mar 20 at: https://www.bhf.org.uk/informationsupport/support/healthy-living/healthy-eating/salt
Harvard T. H. Chan (2019). The Nutrition Source. Salt and Sodium. Accessed online 08 Mar 20 at: https://www.hsph.harvard.edu/nutritionsource/salt-and-sodium/
He FJ, Li J, MacGregor GA (2013). Effect of longer-term modest salt reduction on blood pressure. Cochrane Database of Systematic Reviews 2013, Issue 4. Art. No.: CD004937. DOI: 10.1002/14651858.CD004937.pub2
He, F. J., Pombo-Rodrigues, S., MacGregor, G. A., (2014). Salt Reduction in England from 2003 to 2011: its Relationship to Blood Pressure, Stroke and Ischaemic Heart Disease Mortality., BMJ Open 2014; 4:e004549 DOI:10.1136/bmjopen-2013-004549
LoSalt® (2020). Salt and Your Health. Accessed online 08 Mar 20 at: https://uk.losalt.com/salt-and-your-health/
NHS (2017, 03 March). Others: Vitamins and minerals. Accessed online 08 Mar 20 at: https://www.nhs.uk/conditions/vitamins-and-minerals/others/
NHS (2018, 10 February). Salt: the facts. Accessed online 08 Mar 20 at: https://www.nhs.uk/live-well/eat-well/salt-nutrition/
Public Health England (2017, 30 March). Salt reduction: targets for 2017. Accessed online 08 Mar 20 at: https://www.gov.uk/government/publications/salt-reduction-targets-for-2017