Is salt really as harmful as doctors claim?

Does anyone remember Sid the Slug? The grotesque, slimy character became famous in 2004 when government watchdogs placed the Food Standards Agency's image on billboards and TV ads across the country alongside the slogan: & # 39; Too much salt can cause a heart attack! & # 39;

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The message, if it is to be spelled out, was that salt kills slugs and it is also bad for us humans. Excessive salt consumption leads to high blood pressure – a problem that affects one in ten Britons – dramatically increasing the risk of heart attacks and strokes.

The advertisement has not won any prizes for refinement. However, the £ 15.2 million public health project was considered a success, which led to a reduction in average daily salt intake per person by nearly 1 gram – to around 8 grams or two teaspoons per day. This is considerably lower than the 11g to 12g that the average Brit consumed daily 50 years ago. But it was still above 6g – or one and a half teaspoons – a day recommended to prevent heart attacks and premature death.

So in 2011, in response to growing concern about the & # 39; hidden & # 39; salt in ready-made meals, the British food industry has committed to reducing it. And most importantly, the government agreed to set legal limits.

But somewhere along the line the drive to reduce our salt intake – and campaigns such as Sid the Slug – fell out of the way.

Does anyone remember Sid the Slug? The grotesque, slimy character became famous in 2004 when government watchdogs placed the Food Standards Agency's image on billboards and TV ads across the country alongside the slogan: & # 39; Too much salt can cause a heart attack! & # 39;

Does anyone remember Sid the Slug? The grotesque, slimy character became famous in 2004 when government watchdogs placed the Food Standards Agency's image on billboards and TV ads across the country alongside the slogan: & # 39; Too much salt can cause a heart attack! & # 39;

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Then experts warned last week of the catastrophic aftermath of the current "laissez-faire" approach. Thousands of Britons have had heart attacks and strokes and 1,300 people have died because manufacturers have failed to reduce salt in food, researchers claimed.

Professor Simon Capewell, the author of the study, spoke to The Mail last Sunday and claimed that thousands more would die if no action was taken, and added that & # 39; salt is more harmful than sugar & # 39; . When he published his report, he warned: "The British government's laissez-faire approach will kill or maim thousands of people."

Campaigners are now calling on the government to introduce higher taxes on salty food, similar to last year's sugar tax.

But for years scientific skeptics have been claiming that such public health campaigns about salt are not based on facts. They say there is no real evidence that salt intake actually leads to health problems. Amidst this, the average person has undoubtedly been left confused. So what's the truth – is salt really just as harmful as sugar?

A DEBATE THAT IS SINCE VICTORIAN TIMES

Salt - and in particular sodium, one of its chemical components - is an essential nutrient (stock image)

Salt - and in particular sodium, one of its chemical components - is an essential nutrient (stock image)

Salt – and in particular sodium, one of its chemical components – is an essential nutrient (stock image)

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Salt – and in particular sodium, one of its chemical components – is an essential nutrient. The body needs it for heart, muscle and nerve function and to maintain hydration. But too much or too little can cause problems.

The work to balance the levels is done by the kidneys, which excrete the excess by filtering it out of the blood and depositing it in urine, which is excreted. But the kidneys can only handle so much. If they cannot get rid of it quickly enough, the sodium accumulates in the body, so that more water is sucked into the circulation, increasing blood volume and more work for the heart and more pressure on the blood vessels.

Over time, this can stiffen the blood vessels, leading to high blood pressure, a heart attack or stroke. Or so the theory – which was first introduced more than a century ago – goes like this.

Victorian-era scientists first tried to treat high blood pressure by limiting salt intake, but the results of trials were variable. The tests were also a bit odd – it concerned patients who ate nothing but rice, potatoes, fruit, and cheese.

Researchers later noted that people in Africa who migrated from rural areas (where diets were low in salt) to cities (where diets were more salty) suddenly developed high blood pressure.

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More recent studies have included adjusting the diet of newborns to show that limiting salt intake resulted in lower blood pressure.

And research in the early 1990s showed that limiting salt to four to six grams a day significantly lowered blood pressure in patients with hypertension – the medical name for long-term high blood pressure.

The effect was found to be independent of weight loss. This and other similar findings contributed to the first publication of British salt recommendations in an effort to tackle the rising numbers of hypertension, which now affects one in ten of us.

And the health messages have become thick and fast: salt is an important cause of high blood pressure – and as harmful to our well-being as smoking, obesity and drinking too much alcohol.

But not all scientists are convinced. Over the past 20 years, just as some studies have shown that eating too much salt was bad for your health, and low-salt diets reduce the risk of hypertension, other major studies have contradicted this.

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An article published in 1988 looked at salt consumption in 52 different countries. People in Korea, for example, where the average salt intake is around 12 grams per day, were more likely to have lower blood pressure than residents of countries with low salt consumption.

Over the past 20 years, just as some studies have shown that eating too much salt was bad for your health, and low-salt diets reduce the risk of hypertension, other important studies contradicted this (stock image)

Over the past 20 years, just as some studies have shown that eating too much salt was bad for your health, and low-salt diets reduce the risk of hypertension, other important studies contradicted this (stock image)

Over the past 20 years, just as some studies have shown that eating too much salt was bad for your health, and low-salt diets reduce the risk of hypertension, other important studies contradicted this (stock image)

Two further assessments of salt reduction studies, in 2003 and 2004, showed that following salt reduction advice by the government only marginally lowered blood pressure.

The Cochrane collaboration – an independent health research agency – concluded: "There is little evidence for a long-term benefit of reducing salt intake."

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WHY SALT AFFECTS PEOPLE DIFFERENTLY

First, there are problems with studying how salt in the diet affects health. "It is difficult to measure how much salt people actually eat," explains professor Peter Sever, who has been researching the subject for three decades.

"The only real way to do this is by testing their urine to see how much sodium they excrete.

& # 39; Because we eat different things on different days, you have to collect all the urine that a person produces – up to two liters – for seven days to get an accurate picture. And of course this is not possible in any large-scale way. & # 39;

In addition, measuring blood pressure is also notoriously difficult because it fluctuates during the day – it affects everything from changes in temperature to stress.

Salt is not the biggest concern for cancer

What about the relationship between salt and stomach cancer? In 2012, a report from the Global Cancer Research Fund claimed that one in seven cases of the disease could be prevented if everyone reduced their salt intake to the recommended daily limit of 6 grams in the UK.

But the recommendation was based on studies that found an increased risk of stomach cancer in countries where a salt-heavy diet is popular, such as Korea. The average intake there is around 12 grams per day, much higher than ours.

"We often see stomach cancer in countries where diets contain a lot of salt preserves," said oncologist Dr. Hendrik-Tobias Arkenau, an expert in stomach cancer.

"There is also concern about salted meats such as bacon and sausage, which are related to gastric, intestinal and other gastrointestinal cancers.

& # 39; But the risk is believed to be due to nitrites, chemicals used during the curing process. In western countries, the greatest risk factors for stomach cancer are age, genetics, smoking and infection with a common stomach virus, helicobacter pylori. & # 39;

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H. pylori was also cited in the Asian studies – researchers assumed that a salt-rich diet damaged the stomach lining and increased the risk of the bacteria.

But Dr. Arkenau said the data cannot only be applied to Britons, who have a different diet and a more modest salt intake. "In terms of nutrition, it is generally unhealthy eating, drinking too much alcohol and obesity are the problems – not the salt itself," he says.

"You could see stomach cancer in a person with an unhealthy diet that also contains a lot of salt, but that doesn't mean that salt has caused the cancer.

"Would I tell someone with stomach cancer to stop eating salt? It would not be at the top of my list. & # 39;

"A 24-hour monitor is the best way to get a measurement," says Prof Sever. & # 39; But again, doing this on a massive scale is unrealistic. & # 39;

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Biological response to salt also varies between individuals. "In terms of blood pressure, some people are more sensitive to salt than others," says Professor Thomas Sanders, an expert in nutrition and diet at King's College London. It seems that some people can consume a lot of salt without affecting blood pressure. "But we think about a third of people are very sensitive, perhaps because of genetics," adds Prof. Sanders.

Ethnicity is important, with studies showing that people of Afro-Caribbean and Bengali descent are more sensitive to salt-rich diets. Age is another factor. "Older people are particularly sensitive to salt," explains Prof. Sanders. "The risk of blood pressure only really becomes relevant when you reach 50."

With age, the body is less able to expel excess salt from the body, which leads to water retention and raising blood pressure. Prof. Sanders adds: "People who often exercise or work intensively physically, lose salt due to sweat and therefore have to eat larger amounts. In general, if you are young and healthy without high blood pressure, you do not have to worry about salt. & # 39;

Prof Sever, however, insists on caution: "If you don't have high blood pressure, salt reduction won't make it fall.

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"But the damage caused by salt is due to lifelong eating habits, and problems are only seen with age."

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Blood pressure is not the only problem. "High levels of salt in the bloodstream also damage blood vessels over time, and this is also the risk of serious health problems," says Prof Sever.

"Of course there are other factors – other elements of diet and lifestyle, as well as genetics. But salt is a piece of the puzzle. & # 39;

SHOULD WE GO UNTIL OUR SALT RECORDING?

In the UK, current guidelines suggest that we should not exceed six grams per day. However, the World Health Organization, responsible for international health guidelines, only allows five grams per day. Some salt skeptics claim that there is no reason to limit intake. So who should I believe?

Scientists from all sides of the debate seem to agree that it is unlikely that health will focus on exact amounts of one nutrient.

Prof. Sanders says: "The standard advice does not apply to everyone. Salting zooming won't make a big difference to most healthy people. In the UK we are not doing so badly in terms of salt consumption. If you eat the British average of eight grams per day, this is not a problem.

"It's those people who eat 15 grams a day, or a lot of soy sauce every day, who are most at risk for high blood pressure."

Studies show that even when patients with high blood pressure are advised to reduce their salt intake, they rarely follow instructions (stock image)

Studies show that even when patients with high blood pressure are advised to reduce their salt intake, they rarely follow instructions (stock image)

Studies show that even when patients with high blood pressure are advised to reduce their salt intake, they rarely follow instructions (stock image)

Even Prof Sever, co-founder of the Action on Salt campaign group, admits that it is a "waste of time" to tell people to regulate self-salt in their diet without giving them detailed advice on how to handle it.

Indeed, studies show that even when patients with high blood pressure are advised to reduce their salt intake, they rarely follow instructions.

A 2018 study in the European Heart Journal showed that medication, compared to doctors' advice on salt, was much more reliable and effective for lowering blood pressure. Prof Sever adds: "Scientists who say that salt has nothing to do with blood pressure are wrong.

"But really, the problem is not just about salt or sugar or fat. It's all about them, and the amount of food we eat, how much alcohol we drink and how heavy we are.

"If you follow a diet with many calories, poorly nutritious food, and an inactive lifestyle, this will have a negative effect.

"People with a healthy, balanced diet and an active lifestyle usually have a healthier weight and have fewer heart attacks and strokes.

"So much of what we eat comes from ready-made food and eaten meals, which makes it harder to control what we consume.

"So it is really the job of the food industry to lower the salt content – but they are reluctant, because adding salt is an easy way to make inexpensive, mild ingredients taste good."

Prof. Sanders agrees: "Obesity influences blood pressure much more than just salt intake. Not to mention the many other health complications that it entails. & # 39;

So what should we, the eaters, do about salt? The answer is the same as how we should approach every other ingredient.

Eat it, but not too much, as part of a healthy, balanced diet – and don't think about it too much. And leave the science to the scientists.

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