Salt is such a basic item in our lives that we hardly give it a thought – unless we have run into the thought police telling us that too much salt is bad for us.
Which sounds odd to me really. We are accustomed to adding salt to most meals and to hearing phrases meant to praise someone like "The salt of the earth" which is a very welcome compliment indeed.
So in this post I'd like to look at salt and ask is it really a killer or is it a health food – even the salt of the earth?
At the centre of conflicting evidence and allegations about salt – with some people stating that salt is an essential mineral for our heath and others claim that salt causes higher blood pressure and heart disease – is an almost complete misunderstanding about the real causes of diseases of the heart and arteries.
In the 1950s some research on heart disease and diet was claimed by a researcher called Ancel Keys to show that heart disease was caused by consuming a diet high in animal fat and cholesterol.
That was wrong but has been taken as the orthodoxy ever since then. Heart disease is mostly caused by damage to the inner walls of the arteries and heart caused by oxidation of the cholesterol.
And what causes the oxidation? Short answer – malnutrition and in particular, very low amounts of vitamin C in the diet.
The same basic mechanism is at work about Salt too. A totally safe and indeed essential nutrient – cholesterol in the first case and salt in this case is misunderstood and the real cause is again insufficient intake of essential nutrients.
The InterSalt Study
If a research study is going to come to worthwhile conclusions it needs to have a lot of people in it and to be done according to sensible scientific methods.
The Intersalt study had over 10,000 volunteers from 52 centres around the world. The results showing the connection between Blood Pressure and Salt in the diet is shown in this graph
Looking at this mess of points it is hard to come to any simple clear conclusion although some people did exactly that.
What the authorities wanted to find was a simple one.
The story they wanted to tell was – if you don't eat much salt you'll have low blood pressure and heart disease and if you eat lots of salt you'll have a higher blood pressure and more heart disease.
Let's show you the graph again with a wee dash of colour…
In this I have popped a little red on the first 4 results. These 4 stand out like a sore thumb because they tell such a different story to the other 48 results.
These 4 are results from 2 groups of Brazilian Amazon Indians, Papua New Guinea and Kenya.
They have very low blood pressure and seem to show that BP rises with salt intake – even though the salt in their diets was minimal. The line that can be drawn through the points goes up strongly to the right as most expect.
However, when we turn to the other data things change a lot!
The 48 black points can't be connected with one simple straight or even curved line but when you draw an average line through them show a slight curve downwards to the right.
This means that as salt increases in the diet the blood pressure goes down.
So can take any conclusion from this huge study that we want and that is exactly what happened. There are really 2 sets of results – we have the outlier results from the very isolated communities – shown in red and the other results shown in black.
This has to make you suspect that either something went wrong with the readings or that these rare and isolated amazon and other tribes are slightly genetically different.
If I saw that graph from one of my students – I'd tell them to do the "red" results again to check them.
But of course what you do if you want to tell a particular story is just draw an average line to the whole 52 points and not listen to the data at all.
For me this InterSalt study says little that is at all clear. It needs repeating! Then we don't need to take the results with a pinch of salt.
Are there other studies we could look at for further info on salt and hypertension? Sure how about this one that says, in geek speak,
" A meta-analysis of these trials documented that a median reduction in urinary sodium of ≈1800 mg/d lowered systolic/diastolic BP by 2.0/1.0 mm Hg in non-hypertensive individuals" Quoted from http://circ.ahajournals.org/content/123/10/1138.long
To translate that – drop salt and your blood pressure might drop by 2 mm!! This ridiculous. Sit down and relax for 5 minutes and you can drop your BP by more than that; have a nice cuppa tea and you'll relax with consequential BP drop…etc I don't want my sarcasm to be too blunt here but looking through research papers you get big talk and tiny results.
Sure, read this quote…
"Conclusions In this population-based cohort, systolic blood pressure, but not diastolic pressure, changes over time aligned with change in sodium excretion, but this association did not translate into a higher risk of hypertension or CVD complications. Lower sodium excretion was associated with higher CVD mortality." ( my italics)
In my opinion salt is innocent and blaming it for high blood pressure is a result of not knowing the real causes of high blood pressure and heart disease and poor grasp of statistics which would allow them to see that the so called proof is nothing of the kind.
Salt is fine – but which salt should we be eating?
Is All Salt The Same?
Nearly all salt sold in the shops is sodium chloride so it has only sodium and chlorine as elements with tiny amounts of other minerals. Perhaps it has some iodine added and some "anti-caking" agents to help it flow out of the package.
That is what we might call average salt and is not what I use or what I advise.
I much prefer "sea salt" or Himalayan Salt. The mineral content is much higher in either of these than in average supermarket salt and that can often be noticed by the colour of the salt.
Some of these mineral rich salts are grey and others are pink! This looks at odd at first but the taste is superb and will convince you to stick with it.
Heart disease is serious and is a major killer. It is a tragedy that since the 1950s the orthodox medical profession has been in total confusion about the real causes of arterial and heart disease. Simply put they are symptoms of vitamin deficiencies and for their treatment need careful supplementation. Blocked arteries are not clogged up with cholesterol- they are inflamed and need anti-inflammatory vitamins to help soothe the damaged inner lining of the blood vessels.
Cholesterol is involved since the body uses it to help mend the damage in the walls of the artery like a builder or decorator smooths a wall before painting it. Calcium is involved too because vitamin imbalances often result in calcium building up in the arteries.
This can be fixed easily by taking vitamin K2 – found in Brie cheese. Maybe the reason that French people live long healthy lives is because they eat lots of Brie and get enough vitamin K2?
This could be part of the explanation of what we call the "French Paradox".
Heart disease is complex and if you have a diagnosed heart problem then my advice is to work with a medical professional who understands the correct role in your problem of vitamins such as C, K2 and others which are not mentioned in this article.
One simple thing for sure – salt is innocent so ignore the alarmism and take your vitamins!