Facts on Salt
This week has been World Salt Awareness week, a week designed to increase the awareness of the health effects of too much salt in our diet, alongside giving helpful advice on how we can cut down on the salt in our diet. I am particularly thrilled that this year the theme of the week is ‘less salt, more flavour’. Instead of focusing on all the negatives around salt, this week is celebrating cooking nutritious meals, and how we can enhance the flavours of our home cooked meals...less negativity and more positivity, just what I like to see!
This post will focus on all things salt.
What is salt and why do we need it?
Sodium chloride is the chemical name for salt; it is a mineral that is found in rocks and seawater. Table salt (the kind we find in our cupboards) contains 97 to 99% of sodium chloride and is mined salt from rocks which his processed and refined ready for us to use in our cooking.
Humans have around 250 g of salt in the body. It is mainly found in the extracellular fluid meaning in our blood and the in the fluid around our cells. Sodium is also known as an electrolyte; the mineral carries a charge when it is dissolved in liquid – a very important characteristic enabling it carry out, any important functions in our body! We obtain sodium through food and we lose it through sweating and urine. Sodium has several functions in the body, it enables us to keep the correct amount of fluid in the body and is involved in normal nerve and muscle functioning .
Why do we add it to food?
Salt is found naturally in animal food sources, but less so in plant foods such as fruits and vegetables. Salt has been used for thousands of years as a preservative for many foods including cured meats, such as salami and bacon. Nowadays it is found in high amounts in canned and processed foods used as both a preservative and as a flavouring. Salt is also used in baking in the form of sodium bicarbonate, and as a flavour enhancer known as monosodium glutamate.
In the UK, most of the salt we consume comes from processed foods and foods eaten outside of our homes, about 75% of our salt intake! Foods such as bread, ready meals, pizzas, crisps, pasta sauces, tomato ketchup and breakfast cereals contain large amounts of salt.
The recommended salt intake for a UK adult is 6g per day, which is about 1 teaspoon of salt! However, on average we consume around 8.1 g per day. The average salt intake has lowered over the past few decades which can be attributed to changes in the formulation of processed foods, whereby the food industry now adds less salt. However, as you can see, we all still need to cut down on the amount of salt that we are consuming. The WHO has issued a global target of consuming no more than 5 g of salt per day by 2025, therefore as a nation we still have a long way to go to cut down to these levels .
Why is too much salt is bad for us?
It is common knowledge that high intakes of salt is bad for our health, but why is salt bad for our health and why must we as a nation decrease our intake?
High levels of salt intake have been associated with high blood pressure. High blood pressure also known as hypertension is a major risk factor for both coronary heart disease and stroke. Hypertension is a chronic condition whereby the blood pressure in the arteries is continually high. Blood pressure is caused by the blood pumping against the blood vessel walls; the higher your blood pressure is, the harder your heart must pump – this is what increases your risk of heart disease and strokes.
The reasons as to why a high salt intake causes an increase blood pressure are still debated. It is thought that high amounts of salt can cause you to retain more water, thus increasing blood pressure. However, a definitive answer is still being debated .
There have been multiple studies and meta-analysis (a study analysing many studies together) which have been undertaken which show a clear correlation between lowering salt intake and lowering blood pressure. Lowering salt intake has a bigger effect on those who have been diagnosed with hypertension and less so with those who are normotensive (those with normal blood pressure). Additionally, individuals aged over 55 have been shown to have higher blood pressure than younger individuals, therefore decreasing salt intake in older populations again has more of an impact on their health than in younger people . However, hypertension develops over a prolonged period, so everybody should be focusing on reducing salt intake, no matter how old you are or what your blood pressure is. Decreasing your salt intake will ultimately decrease your risk of developing chronic diseases such as coronary heart disease later in life.
A meta-analysis and systematic review published in 2013, which incorporated 34 randomised control trials looked at a reduction in salt intake and corresponding blood pressure of these individuals, compared to individuals who did not alter their salt intake. The studies which were analysed all involved reducing salt intake by 2.7 to 7 g per day. This meta-analysis determined that a reduction in salt intake over 4 months caused a significant decrease in blood pressure in both people who suffered from hypertension and normotensive individuals. This paper, along with many other papers published show that on a population level reducing salt intake can significantly lower blood pressure and potentially can save many lives .
It has been estimated that if we cut down to the recommended salt intake of 6 g per day, then it will save a total of 4,147 deaths from fatal strokes and heart attacks and the same amount of non-fatal strokes and heart attacks, each year. Additionally, it will also save the NHS £283 million! 
MYTH BUSTER: Over the past few years I have seen more and more advertisement for salt varieties such as pink rock salt. There seems to be health claims attached to this form of salt suggesting that it is ‘healthy’ salt or that it is ‘better for us’ than our normal table salt. Unfortunately, salt is salt, no matter what colour or how refined it is. A high intake of any type of salt will still cause an increase in blood pressure. Pink rock salt is less refined than table salt meaning that it contains more trace elements and minerals. However, these very very small amounts of minerals will not outweigh the negative effects that the excessive consumption of sodium will have on our health.
How can we reduce amount of salt we are eating?
As I mentioned earlier, the theme of this year’s salt awareness week is ‘more flavour, less salt’. This theme focuses on using other types of seasonings such as herbs and spices instead of adding salt to our food.
Other top tips to reduce our salt intake:
Try to avoid or cut down on the amount of processed food that you buy. Or if you are tempted by a ready meal (we all are!!) then try to find an option which again contains less salt.
Opting for foods with a lower salt content.
The traffic light system on food packaging is an easy way to find out how much salt there is in certain food. Try opting for foods which have an amber, or even better a green salt label. This is particularly important when looking at snacks as these snack foods such as crisps (even those ‘healthy’ alternatives tend to be very high in salt).
TOP TIP: salt labels on some food packaging can be confusing and can differ between products as sometimes its labelled as ‘salt’ and other times its labelled as ‘sodium’. Salt and sodium are measured differently, so the values on the labels will be different between the two. Below is an example of the traffic light system with the different limits for green, amber and red for both salt and sodium .
For more information, helpful tips and yummy recipes to help us reduce our salt intake, head to the Action On Salt website!
Geissler & Powers, Human Nutrition, 13th Edition, 2017