One in three Australian adults has high blood pressure (hypertension). Excess salt (sodium) increases the risk of high blood pressure so everyone with hypertension is advised to reduce salt in their diet.

But despite decades of strong recommendations we have failed to get Australians to cut their intake. It’s hard for people to change the way they cook, season their food differently, pick low-salt foods off the supermarket shelves and accept a less salty taste.

Now there is a simple and effective solution: potassium-enriched salt. It can be used just like regular salt and most people don’t notice any important difference in taste.

Switching to potassium-enriched salt is feasible in a way that cutting salt intake is not. Our new research concludes clinical guidelines for hypertension should give patients clear recommendations to switch.

What is potassium-enriched salt?

Potassium-enriched salts replace some of the sodium chloride that makes up regular salt with potassium chloride. They’re also called low-sodium salt, potassium salt, heart salt, mineral salt, or sodium-reduced salt.

Potassium chloride looks the same as sodium chloride and tastes very similar.

Potassium-enriched salt works to lower blood pressure not only because it reduces sodium intake but also because it increases potassium intake. Insufficient potassium, which mostly comes from fruit and vegetables, is another big cause of high blood pressure.

What is the evidence?

We have strong evidence from a randomised trial of 20,995 people that switching to potassium-enriched salt lowers blood pressure and reduces the risks of stroke, heart attacks and early death. The participants had a history of stroke or were 60 years of age or older and had high blood pressure.

An overview of 21 other studies suggests much of the world’s population could benefit from potassium-enriched salt.

The World Health Organisation’s 2023 global report on hypertension highlighted potassium-enriched salt as an “affordable strategy” to reduce blood pressure and prevent cardiovascular events such as strokes.

What should clinical guidelines say?

We teamed up with researchers from the United States, Australia, Japan, South Africa and India to review 32 clinical guidelines for managing high blood pressure across the world. Our findings are published today in the American Heart Association’s journal, Hypertension.

We found current guidelines don’t give clear and consistent advice on using potassium-enriched salt.

While many guidelines recommend increasing dietary potassium intake, and all refer to reducing sodium intake, only two guidelines – the Chinese and European – recommend using potassium-enriched salt.

To help guidelines reflect the latest evidence, we suggested specific wording which could be adopted in Australia and around the world:

Why do so few people use it?

Most people are unaware of how much salt they eat or the health issues it can cause. Few people know a simple switch to potassium-enriched salt can help lower blood pressure and reduce the risk of a stroke and heart disease.

Limited availability is another challenge. Several Australian retailers stock potassium-enriched salt but there is usually only one brand available, and it is often on the bottom shelf or in a special food aisle.

Potassium-enriched salts also cost more than regular salt, though it’s still low cost compared to most other foods, and not as expensive as many fancy salts now available.

A 2021 review found potassium-enriched salts were marketed in only 47 countries and those were mostly high-income countries. Prices ranged from the same as regular salt to almost 15 times greater.

Even though generally more expensive, potassium-enriched salt has the potential to be highly cost effective for disease prevention.

Preventing harm

A frequently raised concern about using potassium-enriched salt is the risk of high blood potassium levels (hyperkalemia) in the approximately 2% of the population with serious kidney disease.

People with serious kidney disease are already advised to avoid regular salt and to avoid foods high in potassium.

No harm from potassium-enriched salt has been recorded in any trial done to date, but all studies were done in a clinical setting with specific guidance for people with kidney disease.

Our current priority is to get people being managed for hypertension to use potassium-enriched salt because health-care providers can advise against its use in people at risk of hyperkalemia.

In some countries, potassium-enriched salt is recommended to the entire community because the potential benefits are so large. A modelling study showed almost half a million strokes and heart attacks would be averted every year in China if the population switched to potassium-enriched salt.

What will happen next?

In 2022, the health minister launched the National Hypertension Taskforce, which aims to improve blood pressure control rates from 32% to 70% by 2030 in Australia.

Potassium-enriched salt can play a key role in achieving this. We are working with the taskforce to update Australian hypertension management guidelines, and to promote the new guidelines to health professionals.

In parallel, we need potassium-enriched salt to be more accessible. We are engaging stakeholders to increase the availability of these products nationwide.

The world has already changed its salt supply once: from regular salt to iodised salt. Iodisation efforts began in the 1920s and took the best part of 100 years to achieve traction. Salt iodisation is a key public health achievement of the last century preventing goitre (a condition where your thyroid gland grows larger) and enhancing educational outcomes for millions of the poorest children in the world, as iodine is essential for normal growth and brain development.

The next switch to iodised and potassium-enriched salt offers at least the same potential for global health gains. But we need to make it happen in a fraction of the time.

Xiaoyue Xu (Luna), Scientia Lecturer, UNSW Sydney; Alta Schutte, SHARP Professor of Cardiovascular Medicine, UNSW Sydney, and Bruce Neal, Executive Director, George Institute Australia, George Institute for Global Health

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Before the COVID pandemic, the World Health Organization (WHO) had made a list of priority infectious diseases. These were felt to pose a threat to international public health, but where research was still needed to improve their surveillance and diagnosis. In 2018, “disease X” was included, which signified that a pathogen previously not on our radar could cause a pandemic.

While it’s one thing to acknowledge the limits to our knowledge of the microbial soup we live in, more recent attention has focused on how we might systematically approach future pandemic risks.

Former US Secretary of Defense Donald Rumsfeld famously talked about “known knowns” (things we know we know), “known unknowns” (things we know we don’t know), and “unknown unknowns” (the things we don’t know we don’t know).

Although this may have been controversial in its original context of weapons of mass destruction, it provides a way to think about how we might approach future pandemic threats.

Influenza: a ‘known known’

Influenza is largely a known entity; we essentially have a minor pandemic every winter with small changes in the virus each year. But more major changes can also occur, resulting in spread through populations with little pre-existing immunity. We saw this most recently in 2009 with the swine flu pandemic.

However, there’s a lot we don’t understand about what drives influenza mutations, how these interact with population-level immunity, and how best to make predictions about transmission, severity and impact each year.

The current H5N1 subtype of avian influenza (“bird flu”) has spread widely around the world. It has led to the deaths of many millions of birds and spread to several mammalian species including cows in the United States and marine mammals in South America.

Human cases have been reported in people who have had close contact with infected animals, but fortunately there’s currently no sustained spread between people.

While detecting influenza in animals is a huge task in a large country such as Australia, there are systems in place to detect and respond to bird flu in wildlife and production animals.

It’s inevitable there will be more influenza pandemics in the future. But it isn’t always the one we are worried about.

Attention had been focused on avian influenza since 1997, when an outbreak in birds in Hong Kong caused severe disease in humans. But the subsequent pandemic in 2009 originated in pigs in central Mexico.

Coronaviruses: an ‘unknown known’

Although Rumsfeld didn’t talk about “unknown knowns”, coronaviruses would be appropriate for this category. We knew more about coronaviruses than most people might have thought before the COVID pandemic.

We’d had experience with severe acute respiratory syndrome (SARS) and Middle Eastern respiratory syndrome (MERS) causing large outbreaks. Both are caused by viruses closely related to SARS-CoV-2, the coronavirus that causes COVID. While these might have faded from public consciousness before COVID, coronaviruses were listed in the 2015 WHO list of diseases with pandemic potential.

Previous research into the earlier coronaviruses proved vital in allowing COVID vaccines to be developed rapidly. For example, the Oxford group’s initial work on a MERS vaccine was key to the development of AstraZeneca’s COVID vaccine.

Similarly, previous research into the structure of the spike protein – a protein on the surface of coronaviruses that allows it to attach to our cells – was helpful in developing mRNA vaccines for COVID.

It would seem likely there will be further coronavirus pandemics in the future. And even if they don’t occur at the scale of COVID, the impacts can be significant. For example, when MERS spread to South Korea in 2015, it only caused 186 cases over two months, but the cost of controlling it was estimated at US$8 billion (A$11.6 billion).

The 25 viral families: an approach to ‘known unknowns’

Attention has now turned to the known unknowns. There are about 120 viruses from 25 families that are known to cause human disease. Members of each viral family share common properties and our immune systems respond to them in similar ways.

An example is the flavivirus family, of which the best-known members are yellow fever virus and dengue fever virus. This family also includes several other important viruses, such as Zika virus (which can cause birth defects when pregnant women are infected) and West Nile virus (which causes encephalitis, or inflammation of the brain).

The WHO’s blueprint for epidemics aims to consider threats from different classes of viruses and bacteria. It looks at individual pathogens as examples from each category to expand our understanding systematically.

The US National Institute of Allergy and Infectious Diseases has taken this a step further, preparing vaccines and therapies for a list of prototype pathogens from key virus families. The goal is to be able to adapt this knowledge to new vaccines and treatments if a pandemic were to arise from a closely related virus.

Pathogen X, the ‘unknown unknown’

There are also the unknown unknowns, or “disease X” – an unknown pathogen with the potential to trigger a severe global epidemic. To prepare for this, we need to adopt new forms of surveillance specifically looking at where new pathogens could emerge.

In recent years, there’s been an increasing recognition that we need to take a broader view of health beyond only thinking about human health, but also animals and the environment. This concept is known as “One Health” and considers issues such as climate change, intensive agricultural practices, trade in exotic animals, increased human encroachment into wildlife habitats, changing international travel, and urbanisation.

This has implications not only for where to look for new infectious diseases, but also how we can reduce the risk of “spillover” from animals to humans. This might include targeted testing of animals and people who work closely with animals. Currently, testing is mainly directed towards known viruses, but new technologies can look for as yet unknown viruses in patients with symptoms consistent with new infections.

We live in a vast world of potential microbiological threats. While influenza and coronaviruses have a track record of causing past pandemics, a longer list of new pathogens could still cause outbreaks with significant consequences.

Continued surveillance for new pathogens, improving our understanding of important virus families, and developing policies to reduce the risk of spillover will all be important for reducing the risk of future pandemics.

This article is part of a series on the next pandemic.

Allen Cheng, Professor of Infectious Diseases, Monash University

This article is republished from The Conversation under a Creative Commons license. Read the original article.