I read an article in Nature magazine a couple of years ago which has nagged at me ever since. It highlighted the sobering fact there has been a collapse in disruptive science.

‘Disruptive’ science has declined — and no one knows why

04 January 2023

The proportion of publications that send a field in a new direction has plummeted over the past half-century.

I recently watched the film Oppenheimer where scientists argued about new ideas. Debating, pushing forward their thinking in exciting new ways. Niels Bohr, Heisenberg, Einstein, Van Neumann, Oppenheimer himself. They seemed like true intellectual giants whose names still echo through history.

In the same era Isaac Asimov was developing new ideas in his novels – the three laws of robotics. Foundation and Empire. Then there was Philip K Dick, Harlan Ellison, Ursula K Le Guin. Where are these giants now? Where is the new thinking? Why has it all got so … dull?

As a child I watched the Apollo moon landings, but when was the last time I woke up to the news that something earth shattering had just taken place in a scientific field? Some form of major disruption. Everything we thought we knew just got turned upside down. New directions …

Although it could seem a little on the trivial side, for me it was with graphene. Two scientists in Manchester were, essentially, larking about in the lab, trying to find out how thin a layer of graphite they could create by wrapping Sellotape round pencil lead. Turns out, you could get a monolayer of graphite. Allowing me to misquote Asimov who reckoned that the most exciting phrase in science is. ‘Well, I never expected that.’

I fully believe that graphene will change the world in many different ways, mainly for the better. A completely unexpected breakthrough in material science. I love this type of thing.

Medical science

Unfortunately, in my world of cardiovascular disease, you could go back fifty years and find almost exactly the same ideas remain in use, about virtually everything. It is hard to think of anything remotely disruptive, or even remotely novel. Cholesterol causes heart disease, check. Diabetics should eat a high carbohydrate diet, check…

Looking specifically at raised blood pressure. What causes it? In ninety-five per cent of people we have no idea. We didn’t know then, and we don’t know now. We still call it “essential hypertension” as we always did, which means – in plain English – a raised blood pressure of no known cause. The proposed management then, and now is … Lower it. Sorted. And we call this progress? Ahem (I say). No disruption here …check.

In this blog I want to look at one, specific area. The use of salt/sodium restriction to lower blood pressure and reduce the risk of dying early? An idea that has been around since before the second world war. Bonkers then, bonkers now. Unchanged …check.

Once some proper scientists managed to fully establish the neurohormonal system that controls blood pressure. Including the renin, angiotensin, aldosterone system (RAAS), it should have become clear to anyone with a functioning brain that restricting salt intake could very well do far more harm than good. An area that is both complicated and fascinating. But this new knowledge had no effect. Nothing was disrupted.

What about the evidence on salt intake. Below, I give you a graph of overall mortality [all cause death] vs. sodium intake ^1.

I do love a graph, but I know a lot of people don’t. So, I shall attempt to explain it in a little more detail.

The bars that rise, and fall, from left to right, represent the percentage of people consuming different amounts of sodium. With most people it falls around the two-to-four-gram mark, or thereabouts. [Which is approximately the same as four to eight grams of table salt, sodium chloride. Most of our sodium intake comes from ‘salt’ but not all].

The solid line, heading down from left to right, shows the risk of death associated with different levels of sodium intake. The shaded area, around the line, represents the spread of ‘probability’. Or, to put it another way, the likelihood that the risk of death at various levels represents a statistically significant finding – at increasing levels of sodium intake. Got that? There will be an exam at the end of this blog.

In essence, though, this graph is very simple to understand. Namely, the more salt you eat, the longer you will live. And, or course, vice-versa. Which is the exact opposite of everything you are constantly told.

I shall repeat this to emphasize the point:

If you eat more salt, you will live longer.

And this benefit continues right up to twenty grams of salt a day. I don’t think they could find anyone who consumed more than that. Although me, swimming in a choppy sea on a sunny day, might manage.

I know what you may be thinking. I have cherry picked one study to make a point. Well yes, this is just one study. However, it is the biggest and longest ever done. It represents one small part of the National Health and Nutrition Examination Survey (NHANES).

And, although it is only a small part, it represents very nearly ‘one-million-person years’ of observation. Of course, like all nutritional studies it has its weaknesses, but you will find nothing bigger, longer, or better than this. And if you want to find one that contradicts it – feel free – and good luck.

But if you would like some more data. Here is the Scottish Heart Health Study. In this case the researchers looked at twenty-seven factors associated – in one direction or another – with cardiovascular disease [although they only mentioned 26?].

They also incorporated overall mortality (risk of dying of anything), and I reproduce their graph, for men, below. The graph for woman was pretty much identical. This was the first time I noticed that increased sodium intake may be beneficial, not harmful ².

Again, a little more explanation is probably required to make sense of this chart. The numbers at the bottom 0 – 4 represent the Hazard Ratio (HR). A hazard ratio of one means the risk of a ‘factor’ is neither raised nor lowered. It is average. Two means risk is doubled, three means risk is trebled etc.

At the top of this chart lies ‘Previous myocardial infarction’ [Previous heart attack]. No surprise to find that having had a heart attack is a pretty good indication of serious problems and a potentially much-shortened lifespan.

There is another thing I need to explain here. You will notice that ‘Previous myocardial infarction’ is ranked +01 – the 01 = the most important factor. The plus sign in front of 01 means that risk of death is increased. If you go down to number five ‘Urine Potassium’, you will see – 05 (minus 05). The minus sign means risk is reduced…ergo, the hazard ratio is reduced. [I shall cover potassium at some point in the future].

If you keep going down the list, you arrive at sodium, at number eleven. As you can see, greater sodium excretion, which is directly related to greater sodium intake, is protective. Sitting at -11. And these researchers actually did a measurement – urinary sodium. Rather than asking people how much salt they consumed each day, because who has any idea about that?

As a further aside if you keep going down you will see the letters NS and NL.

NS = not statistically significant (probably not important one way or the other)

NL = non-linear (there is no consistent association at different levels – risk goes up and down randomly. Definitely not important)

Amongst the NS and NL ‘risk factors’ we find the following:

• High Density Lipoprotein (HDL) a.k.a. ‘good’ cholesterol
• Triglycerides (now considered a form of ‘bad’ cholesterol)
• Total Cholesterol a.k.a. ‘bad’ cholesterol
• Body mass index
• Weight
• Energy intake
• Alcohol
• Blood glucose

None of these things were found to have any effect on the risk of death. Sorry, possibly a bit too much disruptive evidence in one graph for easy digestion. In truth, I could talk about this graph all night, and still have time for more. But I do want to loop back to the start.

‘Disruptive’ science has declined — and no one knows why.’

Both of the studies here could have been, should have been, extremely disruptive. However, they have had no discernible impact whatsoever. Nothing has changed. Here, for example, is what the British Heart Foundation continues to say about sodium:

‘Some food labels call salt, sodium instead. Salt and sodium are measured differently. Adults should have less than 2.5 grams of sodium per day.’ [Approx 5 grams of ‘salt’]

Here is what the CDC has to say, as of today:

‘The CDC recommends that adults and teens consume less than 2,300 mg of sodium per day, which is about one teaspoon of salt.’

[There are many different salts. The one we generally call ‘salt’, table salt, is sodium chloride. NaCl. This is the form of salt from which we obtain most of our sodium. Sodium makes up, very close to, one half of the weight of ‘salt’. So, five grams of salt is around two and a half grams of sodium. No-one eats sodium alone, and it is certainly not recommended. There would be a rather large explosion].

Reading the CDC recommendation did cause my irony meter to reach its maximum recorded level, then break. How so? Because the NHANES graph that I showed earlier comes from research that is funded by, and run by, the Centres for Disease Control and Prevention (the CDC).

Yes, their very own study utterly contradicts their very own advice. Despite this, the CDC continue to harangue us to consume less sodium. Which is not merely health neutral, it is actively damaging. Why don’t they advise people to start smoking while they’re at it?

‘Our studies tell us cigarette smoking damages health. We advise cigarette smoking for all adults. At least ten a day should be tickety boo.’

Sound crazy? Yup.

Now, I know that it is bloody difficult to change an idea. And this has always been the case. To quote Leo Tolstoy from many moons ago:

‘The most difficult subjects can be explained to the most slow-witted man if he has not formed any idea of them already. But the simplest thing cannot be made clear to the most intelligent man if he is firmly persuaded that he knows already, without a shadow of doubt, what is laid before him.’

But science, if it is to be about anything, is the acceptance of new ideas. Disruptive evidence should not be attacked and silenced. Or, in this case, simply ignored. It should be welcomed with open arms. It is the very ground upon which science rests. To quote AI Google on Richard Feynman.,

‘Richard Feynman’s quote, “Science is the belief in the ignorance of experts,” means that genuine science is a process of constant questioning and scepticism, not a blind acceptance of authority. It emphasizes that knowledge is provisional and that experts, while valuable, are limited by their current understanding and should be questioned rather than treated as unquestionable authorities.’

Yes, every ‘scientist’ nods sagely when you say things like this. They then rush off to slam the doors in their minds and carry on regardless.

Were things this bad in the past? I don’t believe so. My sense is that disruptive science has been declining the last fifty years or so …. ‘And no-one knows why?’ But is it true that no-one knows why. Or is that almost everyone does know why, but no-one wants to say it out loud. Or even admit it to themselves. For myself, I believe the answer is, as is usually the case, staring us in the face.

It is money. Or to be more accurate, disruptive science is dying a death due to the enormous effect that financial considerations now have on research. Directly, or in the case of salt, indirectly.

I use the word indirectly because, as you have probably recognised, the impact of money cannot be straightforward with salt. The salt industry, if there is such a thing, can hardly be pushing for a reduction in salt consumption, and who else could get rich from this? So, why do we continue to be bombarded with anti-salt messages. And how can this possibly relate to money?

Next, let me take you on a long and winding golden paved road.

1: https://bmcpublichealth.biomedcentral.com/articles/10.1186/s12889-023-17582-8

2: ‘Comparison of the prediction by 27 different factors of coronary heart disease and death in men and women of the Scottish heart health study:cohort study.’ BMJ 1997;315:722