Nutritionists suggest we cut back on salt but it's sodium you'll see listed on food labels and on any recommended daily intakes. So what's the difference and how can you convert sodium into salt? And vice versa?
Two ways to convert
To help you, I've put together my quick converter table in Step 1 or else use the handy rules in Step 2.
1. Quick sodium and salt converter table
|Sodium in mg||This is roughly equivalent to||Nutrition cut-offs|
|1||400||Good pinch of salt|
|1.25||500||One-quarter of a teaspoon salt|
|2.3||920||One-third of a teaspoon salt||Lower limit of the RDI|
|2.5||1000||Half a teaspoon salt|
|4||1600||¾ of a teaspoon salt|
|5||2000||One teaspoon salt||Aim for this as your maximum day's intake|
|6||2400||1¼ teaspoons salt||Upper limit of the RDI|
|10||4000||2 teaspoons salt|
|12||4800||2½ teaspoons salt||Average intake upper end|
So 5 grams of salt is equal to 2000mg of sodium, both of which are contained in one teaspoon of salt.
If a recipe calls for one teaspoon of salt and serves 4 people, you're getting one-quarter of a teaspoon of salt from it or around 500mg sodium per serve.
2. Use the conversions rules
To convert the sodium to salt or salt to sodium, use these rules:
Sodium to salt
To convert sodium to salt, multiply the sodium figure in milligrams (mg) by 2.5 and then divide by 1,000. So:
millgrams of sodium X 2.5 = milligrams of salt ÷ 1,000
200mg of sodium
200mg x 2.5 = 500mg salt ... then divided by 1,000 = 0.5 grams salt
So 200mg of sodium equates to 500milligrams or 0.5 grams of salt
Salt to sodium
To convert grams of salt to milligrams of sodium, divide the salt figure in grams by 2.5 and then multiply by 1,000 to get milligrams. So
grams of salt ÷ 2.5 = grams of sodium X 1,000
6 grams of salt
6g ÷ 2.5 = 2.4g salt ... then multiplied by 1,000 = 2400 mg of sodium
So 6 g of salt equates to 2400 milligrams of sodium
A little chemistry
Chemically salt is sodium chloride which is made up of one molecule of sodium plus one molecule of chloride. While half the salt molecule is sodium, it's not half by weight. So you can't just halve the weight of salt to find your sodium intake. Sodium is roughly 40 per cent of the weight of salt, with chloride the remaining 60 per cent.
In tiny quantities, both sodium and chloride are essential for health and growth. The problem today is we eat way too much sodium. For more background and tips to reduce your salt intake, click here.
How much sodium is too much?
Our sodium intake should be less than 2300mg per day, roughly a teaspoon (or 6 grams) of salt. Ideally, getting your sodium to less than 1600mg per day is even better as it can help prevent ill health later in life. I suggest you use the mid-point figure of 2000mg sodium as a convenient figure to remember.
But the average daily intake is somewhere between 6 to 12 grams of salt (or 6000 to 12 000 milligrams) which roughly equates to 2 300 to 4 600 milligrams of sodium. So we're consuming double the amount we need.
Sodium - what's low?
Less than 120mg sodium per 100grams.
See the figure of 110mg per 100g in the right hand column of a food label of a low-salt food.
Low-salt foods are unsalted foods such as unsalted butter, canned baked beans or canned tomatoes with no added salt and fresh produce like vegetables, fruits, nuts, milk, fish, meat, eggs, oils, rice, quinoa, barley and other unprocessed grains.
Sodium - what's high?
More than 600mg sodium per 100grams
But this can vary from food category to category eg for bread, any bread under 400mg is considered acceptable; for salty sauces, anything under 1000mg is a good achievement.
Other forms of sodium apart from salt
A food may contain NO salt (sodium chloride) but may still be high in sodium because of the presence of naturally-occurring sodium (as in celery or spinach) or other sodium containing ingredients and additives such as:
|MonoSodium Glutamate (MSG)|
|preservatives||sodium benzoate, sodium nitrite, sodium sulphite|
|antioxidant||sodium ascorbate (the sodium salt of ascorbic acid or Vitamin C). You'll see this as an additive in many white wines under the additive code No 300|
Compare high, medium and lower salt foods
Look at these three categories of compare a similar category food in the high, medium and low category eg corn flakes (highest in salt) vs weet-bix (medium) vs oats (lower).
|Food||Serve||mg sodium per serve||g salt per serve|
|Kellogg's corn flakes||1 cup, 30g||204||0.5|
|Croissant||1, 57 g||424||1.1|
|Kraft Premium crackers, original||4 biscuits, 29 g||234||0.6|
|Lemnos feta cheese||3 cubes, 30 g||310||0.8|
|John West anchovies||6 fillets, 27 g||2,130||5.3|
|Primo bacon||2 rashers, 50g||600||1.5|
|Stock (eg Campbell's chicken)||1 cup, 250 ml||1,118||2.8|
|Soy sauce||1 tablespoon, 20 ml||1,500||3.8|
|Sanitarium Weetbix||2 biscuits, 30 g||87||0.2|
|Golden crumpet||1, 50 g||300||0.8|
|Arnotts Vita weat||4 crackers, 23 g||105||0.3|
|Bega tasty cheese||1 slice, 25 g||153||0.4|
|Greenseas tuna in brine||1/3 cup, 65 g||310||0.8|
|Primo shaved chicken breast||1 serve, 50 g||424||1.1|
|Continental Chicken noodle soup||1 packet, made to 250 ml||765||1.9|
|Masterfoods tomato sauce||1 tablespoon, 20 ml||148||0.4|
|Uncle Toby's rolled oats||1 serve, 40 g uncooked||5||Less than 0.1|
|Sunblest, white bread||1 slice, 30 g||120||0.3|
|Pureharvest rice cakes||2 crackers, 22 g||32||0.1|
|Mainland Mozzarella cheese||1 slice, 25 g||138||0.4|
|Farmer's Best regular milk||1 glass, 250 ml||110||0.3|
|Fresh fish, cooked, no salt||1 serve, 100 g||100||0.3|
|Fresh red meat, cooked, no salt||1 small steak, 100 g||45||0.1|
|Home-made chicken stock, no salt||250 ml||230||0.6|
|Baxter's mango chutney||1 tablespoon, 20 g||84||Less than 0.1|
|Suggested daily maximum||2000||5|
Figures taken from food labels as at 2015
* We have classed these items as "low" compared to other products. However, some of these do not meet the official government definition of less than 120 mg per 100g.
However they are all under 400mg per 100g.
Downloads / Fact Sheets
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