[The Conversation]

Remind Me Again, Why Is Salt Bad For You?​

Despite most of us knowing we should cut down on salt, Australians consume on average almost twice the recommended daily maximum per day.

Salt has been used in food preservation for centuries, and idioms like “worth your weight in salt” indicate how valuable it was for preserving food to ensure survival. Salt draws moisture out of foods, which limits bacterial growth that would otherwise spoil food and cause gastrointestinal illnesses. Today, salt is still added as a preservative, but it also improves the taste of foods.

Salt is a chemical compound made of sodium and chloride, and this is the main form in which we consume it in our diet. Of these two elements, it’s the sodium we need to worry about.

So what does sodium do in our bodies?​

The major concern of consuming too much sodium is the well-established link to the increased risk of high blood pressure (or hypertension). High blood pressure is in turn a risk factor for heart disease and stroke, a major cause of severe illness and death in Australia. High blood pressure is also a cause of kidney disease.

Most of the salt we consume is from processed foods. Shutterstock​

The exact processes that lead to high blood pressure from eating large amounts of sodium are not fully understood. However, we do know it’s due to physiological changes that occur in the body to tightly control the body’s fluid and sodium levels. This involves changes in how the kidneys, heart, nervous system and fluid-regulating hormones respond to increasing sodium levels in our body.

Maintaining tight control on sodium levels is necessary because sodium affects the membranes of all the individual cells in your body. Healthy membranes allow for the movement of:

• nutrients in and out of the cells
• signals through the nervous system (for example, messages from the brain to other parts of your body).

Dietary salt is needed for these processes. However, most of us consume much, much more than we need.

When we eat too much salt, this increases sodium levels in the blood. The body responds by drawing more fluid into the blood to keep the sodium concentration at the right level. However, by increasing the fluid volume, the pressure against the blood vessel walls is increased, leading to high blood pressure.

High blood pressure makes the heart work harder, which can lead to disease of the heart and blood vessels, including heart attack and heart failure.

While there is some controversy around the effect of salt on blood pressure, most of the literature indicates there is a progressive association, which means the more sodium you consume, the more likely you are to die prematurely.

What to watch out for​

Certain groups of people are more affected by high-salt diets than others. These people are referred to as “salt-sensitive”, and are more likely to get high blood pressure from salt consumption.

Those most at risk include older people, those who already have high blood pressure, people of African-American background, those who have chronic kidney disease, those with a history of pre-eclampsia (high blood pressure during pregnancy), and those who had a low birth weight.

Optimal blood pressure is 120/80. Shutterstock​

It is important to be aware of your blood pressure, so next time you visit your doctor make sure you get it checked. Your blood pressure is given as two figures: highest (systolic) over lowest (diastolic). Systolic is the pressure in the artery as the heart contracts and pushes the blood through your body. The diastolic pressure in the artery is when the heart is relaxing and being filled with blood.

Optimal blood pressure is below 120/80. Blood pressure is considered high if the reading is over 140/90. If you have other risk factors for heart disease, diabetes or kidney disease, a lower target may be set by your doctor.

How to reduce salt intake​

Reducing salt in your diet is a good strategy to reduce your blood pressure, and avoiding processed and ultra-processed foods, which is where about 75% of our daily salt intake comes from, is the first step.

Try to use less salt in your cooking, but home prepared meals are not the worst culprit. Shutterstock​

Increasing your intake of fruit and vegetables to at least seven serves per day may also be effective in reducing your blood pressure, as they contain potassium, which helps our blood vessels relax.

Increasing physical activity, stopping smoking, maintaining a healthy weight and limiting your alcohol intake will also help to maintain a healthy blood pressure. Blood pressure reducing medications are also available if blood pressure can not be reduced initially by lifestyle changes.

This article was first published on The Conversation, and was written by Evangeline Mantzioris, Program Director of Nutrition and Food Sciences, University of South Australia

 

[Joyem]

I am already on a low salt, low fat and low sugar diet for health reasons. Yes, I found a lot of tinned foods have too much salt in them and also processed meats as well. So you have to be very mindful of what you can eat. The excepted level is under 400mg to 1 gram in foods.

 

[Mr Chips]

Thank you for this article it was very informative, I suffer from high blood pressure and my GP has prescribed 10mg of Perindopril-Arginine tablet per day. I am diabetic (type 2) and suffer from peripheral neuropathy so I guess I am stuck with this extra tablet each day. I am not a big salt eater but I do need to lose some weight. I exercise regularly, thank goodness for my dog. My blood pressure had climbed recently to 174 so my GP almost went into a panic. It is yet to be decided if the tablet is working as his initial prescription was for only 5mg per day but that only reduced my BP to 143.

 

[Ricci]

I do not, nor have I ever used salt on my food or in my cooking. I had to sit and really think the other week when a visitor brought some chips in and asked for salt, I know I've got a grinder here somewhere!
Any salt I get is what is already put in food when I buy it but I wouldn't mind betting I'm still over the limit.

 

[Wandiwa]

Not sure on the facts here, in Perth as our drinking water becomes more and more derived from desalinated water, I would assume our sodium intake would be be rising.

 

[Penny4]

I'm bad. I love salt, especially on nuts.

 

[Macarj]

Thank you for this article it was very informative, I suffer from high blood pressure and my GP has prescribed 10mg of Perindopril-Arginine tablet per day. I am diabetic (type 2) and suffer from peripheral neuropathy so I guess I am stuck with this extra tablet each day. I am not a big salt eater but I do need to lose some weight. I exercise regularly, thank goodness for my dog. My blood pressure had climbed recently to 174 so my GP almost went into a panic. It is yet to be decided if the tablet is working as his initial prescription was for only 5mg per day but that only reduced my BP to 143.

I had chronic high blood pressure many years ago 25 actually been on tablet ever since and reduced salt intake my tablets are 5mg + 2.5 my blood pressure now is always 120/80 when first discovered I was 188/147 very dangerous

 

[Lynjw]

Remind Me Again, Why Is Salt Bad For You?​

Despite most of us knowing we should cut down on salt, Australians consume on average almost twice the recommended daily maximum per day.

Salt has been used in food preservation for centuries, and idioms like “worth your weight in salt” indicate how valuable it was for preserving food to ensure survival. Salt draws moisture out of foods, which limits bacterial growth that would otherwise spoil food and cause gastrointestinal illnesses. Today, salt is still added as a preservative, but it also improves the taste of foods.

Salt is a chemical compound made of sodium and chloride, and this is the main form in which we consume it in our diet. Of these two elements, it’s the sodium we need to worry about.

So what does sodium do in our bodies?​

The major concern of consuming too much sodium is the well-established link to the increased risk of high blood pressure (or hypertension). High blood pressure is in turn a risk factor for heart disease and stroke, a major cause of severe illness and death in Australia. High blood pressure is also a cause of kidney disease.

View attachment 6423
Most of the salt we consume is from processed foods. Shutterstock​

The exact processes that lead to high blood pressure from eating large amounts of sodium are not fully understood. However, we do know it’s due to physiological changes that occur in the body to tightly control the body’s fluid and sodium levels. This involves changes in how the kidneys, heart, nervous system and fluid-regulating hormones respond to increasing sodium levels in our body.

Maintaining tight control on sodium levels is necessary because sodium affects the membranes of all the individual cells in your body. Healthy membranes allow for the movement of:

• nutrients in and out of the cells
• signals through the nervous system (for example, messages from the brain to other parts of your body).

Dietary salt is needed for these processes. However, most of us consume much, much more than we need.

When we eat too much salt, this increases sodium levels in the blood. The body responds by drawing more fluid into the blood to keep the sodium concentration at the right level. However, by increasing the fluid volume, the pressure against the blood vessel walls is increased, leading to high blood pressure.

High blood pressure makes the heart work harder, which can lead to disease of the heart and blood vessels, including heart attack and heart failure.

While there is some controversy around the effect of salt on blood pressure, most of the literature indicates there is a progressive association, which means the more sodium you consume, the more likely you are to die prematurely.

What to watch out for​

Certain groups of people are more affected by high-salt diets than others. These people are referred to as “salt-sensitive”, and are more likely to get high blood pressure from salt consumption.

Those most at risk include older people, those who already have high blood pressure, people of African-American background, those who have chronic kidney disease, those with a history of pre-eclampsia (high blood pressure during pregnancy), and those who had a low birth weight.

View attachment 6424
Optimal blood pressure is 120/80. Shutterstock​

It is important to be aware of your blood pressure, so next time you visit your doctor make sure you get it checked. Your blood pressure is given as two figures: highest (systolic) over lowest (diastolic). Systolic is the pressure in the artery as the heart contracts and pushes the blood through your body. The diastolic pressure in the artery is when the heart is relaxing and being filled with blood.

Optimal blood pressure is below 120/80. Blood pressure is considered high if the reading is over 140/90. If you have other risk factors for heart disease, diabetes or kidney disease, a lower target may be set by your doctor.

How to reduce salt intake​

Reducing salt in your diet is a good strategy to reduce your blood pressure, and avoiding processed and ultra-processed foods, which is where about 75% of our daily salt intake comes from, is the first step.

View attachment 6425
Try to use less salt in your cooking, but home prepared meals are not the worst culprit. Shutterstock​

Increasing your intake of fruit and vegetables to at least seven serves per day may also be effective in reducing your blood pressure, as they contain potassium, which helps our blood vessels relax.

Increasing physical activity, stopping smoking, maintaining a healthy weight and limiting your alcohol intake will also help to maintain a healthy blood pressure. Blood pressure reducing medications are also available if blood pressure can not be reduced initially by lifestyle changes.

This article was first published on The Conversation, and was written by Evangeline Mantzioris, Program Director of Nutrition and Food Sciences, University of South Australia

I almost never add salt to my cooking but have sl high BP. Unfortunately for those with food intolerances or allergy the safe foods often have extra salt and sugar. As I still work I can’t always make my own foods so have to rely on pre-made bread and crackers and condiments. I don’t buy precooked dinners or cakes and eat fresh fruit and veg. My family has a history of high BP so sometimes it is family history but we all need to cut down and eat more healthier.

 

[Keswickian]

I've never understood how drawing more fluid into the blood vessels increases blood pressure. I would have thought the opposite is true.
Pumping thick (viscous) blood through narrow tubes would require higher (blood) pressure. On the other hand, drawing more fluid into the tubes would thin the blood, increase the volume and expand the tubes requiring a lower pressure to pump it round the system.

 

[Groovy]

My mum used to have very high blood pressure and no medication would bring it down, until a doctor thought it to be strange that medication didn’t work. He checked her lower part of her legs and discover there was something wrong…….. very low pulse! After having tests done, they found out there was a big problem in her aorta. She had to have an operation and the cut was from her chest to the middle of her back. They put a piece of a pig’s artery to substituted her damaged one. After that she was ok, but had to be on blood thinner for the rest of her life.
It’s not just salt that can cause high blood pressure, there are other factors.

 

[Bilby]

What if you are one of the 10% of the population? In 1999 I was hospitalized with a bad case of Menieres. I was connected to an intravenous machine for five days as my electrolyte levels were way too low. Another attack in 2003 , the doctor said my blood pressure was too low. I increased my salt intake and have only had mild attacks that lasted one night. Hypo-tension can be fatal.