Ask The Experts
Dr Mike Smith is a well-known doctor and medical journalist. We asked him a number of questions about salt. Here are his answers.
Do we need salt in our diet at all?
Certainly. There's no doubt about that.
It's composed of both sodium and chloride - main constituents of the tissue fluid in which every cell in the body is bathed and nurtured. This transports the vital oxygen and nutrients from the bloodstream to feed the cells. Also, our bodies use the sodium particles as though they were very small 'sponges'. They attract water to themselves and so make sure that the tissues don't get too dry.
Should most people try to cut down their salt intake?
Yes - I think so.
Why take a risk by eating an excess of salt when the body doesn't need it and when reducing will certainly do you no harm?
The leading salt alternative, LoSalt, contains 66.6% potassium chloride. Is taking potassium in this way okay?
In general, yes. Using a product such as LoSalt will heavily outweigh any disadvantages.
The rare few for whom an increased intake of potassium wouldn't be wise are those whose kidneys are not functioning normally - and so can't dispose of the excess. The majority of such sufferers will know this, having been told so by their doctor or dietician, and been advised about the type of diet appropriate for them. The same goes for very young babies.
Likewise, those with such uncommon kidney problems will be advised to restrict their intake of certain, otherwise nutritious, fruits known to be rich in potassium - bananas and avocado pears, for example.
For everyone else - that is, most of the population - two large bananas a day contain as much potassium as a day's average consumption of LoSalt. And I can't remember anyone suggesting that they had been harmed by eating two bananas a day - quite the reverse!
Just as many specialists believe that sodium intake should be reduced for someone with raised blood pressure, it's likely that an increase in the daily intake of potassium has a blood pressure lowering effect - so that's another potential bonus for LoSalt.
What is high blood pressure?
A doctor will diagnose high blood pressure when the reading taken is permanently higher than the average. The upper limit of normal is about 140 over 90.
These two figures are pressure measurements within the main arteries supplying blood to the body taken when the heart is pumping or contracting (the systolic pressure or higher reading) and when the heart is refilling with blood (the diastolic pressure or lower reading).
If they remain permanently high, the body's organs and tissues can show greater signs of wear and tear over the years and, for example, give rise to a stroke or heart disease.
Diet and exercise alone can reduce a raised blood pressure.
Whether treatment with medicines is given depends upon the level of blood pressure and the patient's age.
Which groups or types are most at risk from taking too much salt?
Blood pressure sufferers especially. It's recommended that they reduce their salt intake and for others, this is probably a good thing to do as well.
At 60 years old, three in every ten will have raised blood pressure. At 70 there are more - two in every five. When such a person restricts their salt intake, their blood pressure falls, sometimes enough to avoid the need for blood-pressure-lowering medicines altogether.
In this group, there's likely to be a more marked rise in blood pressure when excess salt is eaten than can be seen in the average fit individual.
And it may be possible that eating too much sodium throughout life is one of the reasons why, in developed countries especially, people suffer from raised blood pressure at all. It is uncommon to find raised blood pressure in the populations of developing countries where sodium intakes are often lower.
Do women benefit as much as men from reducing their salt intake?
In some ways, women may benefit even more.
A high salt intake causes the body to temporarily retain fluid and in women who suffer from pre-menstrual swelling, or swelling unrelated to menstrual cycle, the symptoms could be relieved by reducing salt intake. Some research suggests that increasing potassium intake may also help to get rid of some sodium - providing another bonus.
Is taking too much salt bad for everyone?
In my opinion, yes.
In a developed country like Britain, one in every ten people has abnormally high blood pressure - hypertension, and the higher the blood pressure, the more likely it is that a blood vessel can burst under the strain. When that occurs in the brain it's called a stroke - which can cause paralysis of movement or of the senses or, when even more severe, a tragedy.
Now eating too much sodium could be keeping everybody's blood pressure a little higher than it need be. And while for somebody with normal blood pressure, this slight and temporary rise may not be too much of an extra risk, the excess sodium could be a contributory cause of permanently raised blood pressure - the hypertension already mentioned - even for them.
However, for someone with established hypertension, eating too much sodium could be the last straw and a stroke could follow.
Also, there are many people who have hypertension but aren't aware of it - so they are at greater risk as well.
People with raised blood pressure are also very much more likely to develop various types of heart problems (cardiovascular disease) resulting in restricted lifestyles and in more acute cases - death.
It's important therefore to look at all the ways of keeping blood pressure down. Reducing salt intake is certainly one of them.
In Dr Mike Smith's opinion:
"If you are on a medically advised sodium (salt) restricted diet, then you must ask your doctor how and if you should use LoSalt.
If you are in normal health, try to do without salt in cooking and at the table, but if you feel you really need a salty flavour for some foods, then use LoSalt."