Eat Too Little Salt?

It has long been held that a diet high in salt is dangerous to the heart, raising the risk of heart attack and stroke.

But, in a dramatic U-turn, the scientific evidence has suggested the opposite can also be true.

A global study has found that contrary to past belief, low-salt diets may not be beneficial.

Rather, they can increase the risk of cardiovascular disease and death, compared with average salt consumption.

The study, published in the reputable Lancet journal, has garnered a strong reaction, with one expert declaring his ‘disbelief’, while others are critical of the study’s methods, and calling its findings into question.

The research was carried out by investigators at McMaster University and Hamilton Health Sciences.

They analyzed more than 130,000 people across 49 countries, focusing on whether the relationship between sodium (salt) intake and death, heart disease and stroke differs in people with high blood pressure compared to those with normal blood pressure.

Their findings showed that regardless of whether people have high blood pressure, low-salt intake is linked to a greater incidence of heart attacks, stroke, and deaths compared to the average intake.

Dr. Andrew Mente, lead author, and associate professor of clinical epidemiology and biostatistics at McMaster’s Michael G. DeGroote School of Medicine hailed the findings ‘extremely important’ for those suffering high blood pressure.

He said: ‘While our data highlights the importance of reducing high salt intake in people with hypertension (high blood pressure), it does not support reducing salt intake to low levels.

‘Our findings are important because they show that lowering sodium is best targeted at those with hypertension who also consume high sodium diets.’

The NHS advises adults in the UK eat no more than 6g of salt each day – around one teaspoon.

In the US, the Centers for Disease Control and Prevention (CDC) recommends Americans consume less than 2,300 milligrams a day. That comes in the face of evidence, suggesting the average American consumes 3,400mg each day.

Meanwhile, in Canada, typical sodium intake is between 3.5 and 4g per day.

However, some guidelines have suggested that the entire population lower their salt intake to below 2.3g a day – a level that fewer than five percent of Canadians and people around the world consume.

In the past, some research has shown that low-salt diets, compared to average intake, is linked to increased cardiovascular risk and mortality, even though low sodium intake is linked to lower blood pressure.

This new study shows that the risks linked with low-salt intake – classified as less than three grams a day – are consistent regardless of a patient’s blood pressure.

Further, the findings show that while there is a limit below which sodium intake may be unsafe, the harm associated with high sodium consumption appears to be confined to only those with hypertension.

Only about 10 percent of the population in the global study had both hypertension and high sodium consumption – defined as greater than six grams per day.

Read the Whole Article

Read more