How Much Salt Is It OK To Eat?

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Australian guidelines recommend limiting salt intake to six grams a day or less. The World Health Organisation advises limiting salt even further: to 5g (for adults) and 2g (for children) per day or less. But how much can you get away with before it starts to become seriously unhealthy? Let's take a look at the science.

What we generally refer to as “salt” – the stuff that we sprinkle on our food – is actually sodium chloride. It’s the sodium from the salt that can lead to high blood pressure when consumed in high amounts.

Usually our kidneys are good at getting rid of excess sodium in the urine. But when problems with this occur, excess sodium enters the bloodstream. This can boost the amount of blood pumped around our body. The increased pressure on our blood vessels and heart raises the risk of stroke, as well as heart and kidney problems.

Lowering your sodium intake will improve your health and reduce your risk of experiencing these problems, largely through the reduction in blood pressure.

One gram of salt contains approximately 400 milligrams of sodium. The maximum daily limit for adults is a little less than six times this figure: 2,300 milligrams of sodium per day.

Children need much less sodium. Limits range from 1,000 milligrams of sodium per day for children aged one to three years, and between 1,400mg to 2,000mg for those aged between four to 13 years.


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The sodium chloride (table salt) we add to other foods during cooking or at the table accounts for less than a quarter of sodium intake. A very small amount of sodium is also present in many foods such as milk and meat that contribute only a very small amount to our overall intake.

Most sodium we eat comes from processed and pre-packaged foods. Sodium is commonly added to foods during processing to add flavour, for preservation and as a raising agent (sodium bicarbonate).

Around 60% of Australians over the age of two years exceeded the recommended daily maximum intake.

The foods that account for the largest proportion of sodium intake in Australian adults (about 25%) include biscuits, cakes, pastries, pies, dumplings, pizza, hamburgers, hot dogs, and pasta and rice mixed dishes.

A few slices of takeaway pizza or a hamburger easily provides around 65% of daily upper limit of consumption, with around 1,500mg sodium.


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Savoury snack foods contain high amounts of sodium. Many sweet snack foods and bakery products often contain high levels of sodium as well. This is usually from added salt and other additives such as sodium bicarbonate, which helps baked goods rise.

An iced vanilla doughnut or low-fat banana muffin can contain up to 650mg of sodium (roughly 30% of the daily upper limit).


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Some other foods we eat everyday, such as breads and breakfast cereals, contribute a lot of salt to our diets. These foods aren’t always really high in sodium but because we eat of a lot of them, it adds up. A continental bread roll such as a panini or ciabatta can provide up to 450mg per roll (20% of the daily upper limit).


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You already know foods such as processed meats and cheeses are very salty, but just how much might surprise you. A few slices of leg ham or a couple of BBQ sausages will provide around half the daily limit of sodium. Combine that with a few slices of bread for a sandwich and some tomato sauce or cheese, and you will have easily exceeded the upper limit of consumption.


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Passing on added salt at the dinner table is a good habit to reduce sodium intake, but take care adding sauces or condiments as these are likely just as salty. Tomato pasta sauce and stir-fry sauces can contribute up to 480mg in a single serve (up to 20% of the daily limit).


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Because sodium is present in so many processed foods – even sweet snacks and baked goods – you shouldn’t always rely on your taste buds to determine how much you’re consuming. So how can you cut down on your sodium intake?

First, eat fewer packaged and processed foods. In addition to sodium, they often contain high amounts of sugar and fat and very little of any other beneficial nutrients. So reducing your intake of these foods can substantially improve the quality of your diet.

Second, swap processed foods for those cooked or prepared at home. Swap sandwich fillings like processed meats with ones you’ve cooked yourself (such as left over roast meat). Opt for fresh fruits and unsalted nuts instead of packaged sweet or savoury snacks.

Instead of takeaway meals like pizza or frozen dinners, prepare home-cooked versions. Here you can use more fresh food ingredients (which are low in sodium) and you can control the added salt. Fresh foods are also higher in potassium, which has beneficial effects on lowering blood pressure.

Finally, read the labels on packaged foods. Food labels in Australia usually give the figure for sodium rather than salt. So if you are reading a nutrition information panel, try to look out for foods that have less than 400mg sodium per 100g of food. Any packaged food labelled less than 120mg sodium per 100g of food is best.

The George Institute and Bupa Australia’s FoodSwitch/SaltSwitch app is a useful tool to help you navigate and compare sodium content of packaged foods on the go. You can scan the barcode of the product you’re considering buying and see a list of other products with less sodium.

How Much Sugar Is It OK To Eat?

If you're an average-sized adult eating and drinking enough to maintain a healthy body weight, you should consume no more than 12 teaspoons of sugar per day. But what does this translate to when it comes to popular foods and beverages? We investigate.

Read more

The Conversation

Kacie Dickinson, Accredited Practising Dietitian; Associate Lecturer in Nutrition and Dietetics, Flinders University

This article was originally published on The Conversation.


Comments

    "Let's take a look at the science".
    Except you haven't.

    In recent years, it's becoming clear that those studies linking salt to high blood pressure are becoming discredited in light of new evidence. This is well-known in medical science now. Did you even bother researching anything recent? What a pathetic attempt at 'science' reporting.

    I'll take Scientific American over "Lifehacker" on scientific issues any day.

    https://www.scientificamerican.com/article/its-time-to-end-the-war-on-salt/

    This paragraph in particular has more science in it than this entire article.

    "This week a meta-analysis of seven studies involving a total of 6,250 subjects in the American Journal of Hypertension found no strong evidence that cutting salt intake reduces the risk for heart attacks, strokes or death in people with normal or high blood pressure. In May European researchers publishing in the Journal of the American Medical Association reported that the less sodium that study subjects excreted in their urine—an excellent measure of prior consumption—the greater their risk was of dying from heart disease. These findings call into question the common wisdom that excess salt is bad for you, but the evidence linking salt to heart disease has always been tenuous."

    Last edited 18/05/17 6:04 pm

    "In recent years, it's becoming clear that those studies linking salt to high blood pressure are becoming discredited in light of new evidence."

    In light of new evidence, WTF. That study is six years old.

    A google search in 2017 shows no support for that study by any health organisation.

    In fact I'll take today's World Health Organisation position on salt over your outdated study any day.

    Along with....

    The British Heart Foundation.

    The National Heart Foundation of Australia.

    The UK NHS.

    American Heart Association.

    British Heart Foundation.

    All health insurance companies.

    Insert any health organisation here________________________

      So to summarize your points:

      1. You didn't Google properly.
      2. You haven't cited any rebuttal studies to the one I cited.

      You realise that since we're only in the 5th month of 2017 that there probably HASN'T been any studies conducted along those lines this year so far, right?

      Here's a study from Oxford in 2014 finding the same NULL results across a sample size of 8000 participants.
      https://academic.oup.com/ajh/article/28/3/362/2743418/Relationship-Between-Nutrition-and-Blood-Pressure

      EDIT: Turns out there WAS at least one study this year which is consistent with this new slew of cross-sectional analyses. I guess you didn't Google for long hey? Here's a write-up.
      http://www.medicalnewstoday.com/articles/317099.php

      Enough yet? Or is Oxford not a legitimate enough institution for you?
      Here's another one for you, this time from 2015.
      http://www.newsmax.com/Health/Health-News/salt-heart-blood-pressure/2015/04/27/id/641075/

      Also as a final point - you realise those organisations you mentioned are usually the LAST ones to change their position on longstanding (incorrect) medical consensus, right? Sometimes they take DECADES, and even then, only if it's politically advantageous. They AREN'T scientific institutions. Probably not the best idea to cite them for the latest information.

      Last edited 18/05/17 8:51 pm

        Thanks for those links.

        Let's take a closer look, shall we.

        https://academic.oup.com/ajh/article/28/3/362/2743418/Relationship-Between-Nutrition-and-Blood-Pressure

        “Globally, salt consumption was higher in hypertensive participants compared with those who were nonhypertensive”.

        Yep! That's what all authorities on the subject say.

        Next!

        http://www.medicalnewstoday.com/articles/317099.php

        
Accompanying articles on that very link are at variance, lol:

        http://www.medicalnewstoday.com/articles/297441.php?sr
        http://www.medicalnewstoday.com/articles/288435.php?sr

        Did you even bother to read the those links debunking your own assertion?

        Next!

        http://www.newsmax.com/Health/Health-News/salt-heart-blood-pressure/2015/04/27/id/641075/

        I love the following links that particular website provides, ergo:

        • Itching This Part of Your Body Is a Sign of Alzheimer’s 

        • Why Doctors in the Know No Longer Prescribe Metformin 

        • How To Fix Your Fatigue (Do This Every Day) 

        • Simple Method "Regrows" Hair. Do This 

        • Do This Tonight to Make Fungus Disappear by Morning

        • Why Doctors in the Know No Longer Prescribe Metformin 

        • Simple Method "Regrows" Hair. Do This 

        • Odd Chinese Remedy 'Destroys' Nail Fungus in 1 Day 

        • Why Doctors in the Know No Longer Prescribe Metformin 

        • Simple Method "Regrows" Hair. Do This

        All flogging off alternative medicine like this one:

        http://regrowhairprotocol.com/?aff_id=13625&subid=wPUIV595H4AI0SE518M1R21Q

        What’s your next link, how to regrow a severed arm?

        If I were you I’d quit while you’re behind.

          So to summarise your argument:

          1. You've found correlation, but not causation, especially in the face of the studies I've linked you to, which clearly show that there is no causation there, and actually cite the studies you've linked to, and explain WHY those studies haven't found a causation.

          2. You've completely ignored the Oxford study published this year.

          3. You've pointed to other content on a website I've linked to in order to discredit a study that has NOTHING to do with the website. Did you even bother to search for the actual study the article is talking about? Wait, don't answer that, because you couldn't even manage to find a study from this year, and I found one from Oxford in 5 mins. The studies themselves are about as legitimate as you can get and you can find them in pubmed if you bothered to look.
          https://www.ncbi.nlm.nih.gov/pubmed/25194158

          Just because a single website is not a great source of journalism, it doesn't mean the study it references is any less legitimate. Even a broken clock is right twice a day.

          4. You completely ignored the part of my post where I tell you that NONE of these organisations are scientific organisations themselves, and instead rely on other scientific institutions to form their policies - meaning that they don't necessarily reflect the most accurate, recent evidence.

          Do you actually have ANYTHING AT ALL to dispute the studies I've linked you? Or do you actually think that pointing somewhere and saying "PFFT this thing says what I believe so you're wrong" is a great argument?

          Last edited 19/05/17 8:48 am

            I'm sorry, Corvus, but your credibility's been totally shredded.

            You provided the following link to support your claim that salt does not contribute to high blood pressure:

            "High blood pressure: Sodium may not be the culprit"
            http://www.medicalnewstoday.com/articles/317099.php

            I guess you didn't notice the word "may" in the heading.

            But quite apart from that, on the very same webpage that you yourself provided, two other articles declared that salt *is* in fact linked to high blood pressure....

            "Gradual increase in salt intake linked to high blood pressure"
            http://www.medicalnewstoday.com/articles/297441.php?sr

            Salt may raise blood pressure by disabling safety mechanism in the brain"
            http://www.medicalnewstoday.com/articles/288435.php?sr

            Talk about a massive own goal.

            As I said your credibility's been irretrievably destroyed.

            You do see that, surely.

        As @corvus stated, it can take a long, long time for national/international dietary guidelines to be adjusted as evidence emerges. I think there are lot of old guidelines based on correlations (e.g. the standard food pyramid) that are slowly being challenged for their validity. As for salt here is just one study (probably reference by @corvus in later posts) : http://www.nejm.org/doi/full/10.1056/NEJMoa1311889#t=article
        Here is the chart of interest which shows a correlation that lower sodium actually presents a greater risk of death than eating higher amounts: http://www.nejm.org/na101/home/literatum/publisher/mms/journals/content/nejm/2014/nejm_2014.371.issue-7/nejmoa1311889/20160608/images/large/nejmoa1311889_f1.jpeg

          Exactly.
          The 'food pyramid' is a perfect example of how political/lobby interests skew the science enough so that 'health' organisations end up advocating something for DECADES that isn't necessarily based in rigorous scientific evidence.

          Simply ignoring this evidence just because these organisations support it is just like saying "it's true because everyone I know says its true" - essentially the 'appeal to the populace' (but specifically the 'appeal to authority').

          "It can take a long, long time for national/international dietary guidelines to be adjusted as evidence emerges."

          And rightly so, that's why there aren't knee-jerk reactions by the World Health Organisation, Heart Foundations, national health services, etc, to studies they feel may be flawed...
          http://news.heart.org/experts-criticize-new-study-about-salt-consumption/

          The fact is, the organisations I listed above don't rely on one or two studies to determine health guidelines but base their assessment on the *totality* of scientific research which is why they are unequivocal in stating that excessive salt in the diet is a significant risk factor in cardiovascular disease.
          http://www.who.int/mediacentre/factsheets/fs317/en/

          And of course, just as scientists were once employed by the tobacco industry to dispute the link between smoking and cancer, and just as some scientists are in the pay of the fossil fuel industry to dispute the science of anthropogenic global warming, it may be prudent to allow that some scientists may in fact be in the pay of the multi-billion dollar fast-food industry.

            I completely agree that these bodies should take a considered and evidence based approach for their recommendations. But many concerns have been raised about the validity of the studies/research the current guidelines are based on. Correlation vs causation is a major issue with all these studies and the conclusions they draw.

              Thank you, @nosoupforyou, you beat me to it.
              Totally agree that these non-scientific institutions should be slow to adopt the latest evidence, however let's not pretend that's the ONLY reason they're resistant to doing so. These institutions also receive quite a bit of political pressure to adopt the positions they do.

              Funny dreadnought mentions the tobacco point - most of these institutions didn't officially admit that tobacco causes lung cancer until WELL AFTER the scientific consensus agreed on it. Point being, they are NOT a great source to go to for the newest and most accurate scientific conclusions.

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