One of the most common things I hear throughout the day when I talk about eating a low sodium diet is ‘I don’t use the salt shaker.’ Using salt shakers is the least of our problems. The message is: Salt is in everything we eat, from cereal to soda.
Salt is sodium chloride. When we talk about salt intake we will be talking about sodium because that is what is on all the labels. But the word ‘salt’ is what most of us say, so I use both sodium and salt.
Why Should You Care How Much Sodium You Eat?
First, the more salt you eat the higher the level of calcium you will find in your urine. When you have more calcium hanging around in the urine your chance of forming more stones increases. Then there are your bones. More salt will rob your bones of calcium and kidney stone formers are at risk to develop bone disease. Although blood pressure is not the main issue for this site, high salt diets do increase blood pressure and reducing salt intake is recommended by all authorities.
How Much Sodium Should You Eat?
We already have a very long article on this site about ‘how much‘. The CDC, and the AHA, and the science concerning calcium balance all point to one optimal level: 1500 mg daily. That is an ideal. The same two authorities say that 2000 mg/day is the upper limit for the US population. The CDC and AHA, incidentally, are not interested specifically in kidney stones or even bone disease, but in blood pressure – a major killer.
How Do You Know How Much Salt You are Eating?
The easiest way to know how much sodium is in your food is to read the nutrition label. 
The problem is that the information is sodium per serving, and servings per package.
The image on the left is a can of Campbell’s Tomato Soup. I like to use it as a classic example because we typically think this is a healthy lunch.
Mr Campbell says there are 2.5 servings in this one can. You and I eat it as one. Each serving – look at the label – is 480 mg of sodium. The whole can – 2.5 servings – is 1,200 mg – just about the whole day’s worth.
Anything in a bag, can, wrapper, or container will have lots of sodium in it unless it says ‘low sodium’ and even then you should look at the label and consider what the producer considers low sodium.
Here is the ‘Reduced Sodium’ version. Without looking at the numbers you would think this was healthy and a safe bet. But basically since we know there are 1,200 mg of sodium in a can of regular tomato soup, 25% less is still a lot of sodium: 900 mg of 
sodium.
There is nothing dishonest about what Campbell Soup is doing here. They are telling you exactly what is in their soup. It is up to you to calculate how much and remember you will probably use the whole can for your lunch, not 1/2 of the can which is ‘one serving’.
The message is this: You must do your homework. You have to realize how much sodium is in each food you eat by reading your labels, and you have to realize how many servings you are eating in one sitting. You can’t blame the food industry. They are doing their part and showing you what they do. It is up to you to do yours.
What About Dining Out?
There are no labels. Now what?
You can rest assured that eating out will cost you thousands of milligrams of sodium in most cases.
All meats, cheeses, salad dressings, even your vegetables will likely be salted – and buttered, that’s why dining out is so yummy.
You can always ask your server to request the chef not to put extra salt in or on your food. But even so it will be higher in sodium than if you cooked your food at home.
So, the only answer: Eat out less. Pack your lunches.
I work with business people who have to go out every night with clients. For breakfast and lunch they just have to watch their sodium carefully to make up for the huge loads at supper.
Some of you may not eat out on a regular basis, but when you do happen to have a high sodium day just drink a lot of water in the morning and watch the sodium for the next few days. It takes a few days to get rid of a salt load.
How To Cook At Home
First step: Don’t use any added sodium while you’re cooking.
Try finding recipes with different types of herbs that will add healthy flavor to your meal. Tarragon, basil, rosemary, garlic, and anything else that appeals to you – all good choices.
At first you are definitely going to notice a change in taste to your foods. But in my fifteen years of doing this work helping clients, I have found that even with my worst salt addicts it is only a few weeks before they start noticing when a food is super salty and they don’t like it.
If you do not cook with salt then you can add a little salt at the table. I like fancy sea salts because they taste better and a little bit goes a long way.
Hidden Salt in your Favorite Foods
Here is my list of food types that usually contain a lot of salt but you might not think about it or check out the label:
- Olives
- Bread
- Canned foods – all kinds
- All pickled foods
- Cheeses
- Deli meats
- Cereals
- Pizza
- All fast foods
- Condiments – Soy sauce even reduced sodium, mustard, ketchup, etc
- Sauces
- Salad dressings
Online Lists
In our long article on salt, we linked to several sites that give sodium content of foods by product. If you find others, please let us know and we will add them.
How to get Started
This isn’t as hard as you think.
The most important thing you can do to lower your salt is to understand where it is coming from. Once you realize that going out to eat and certain food categories are the main culprits, and that nutrition labels are your guides, it is all very doable.
After you eat a diet lower in salt, trust your taste buds.
They are going to be a very useful tool in recognizing what foods are high in salt. I promise you it really only takes a few weeks to notice the difference. Once you do you will always notice salty foods and probably won’t want to eat too much of them.
Salt and Water
When I look at a 24 hour urine result the first thing I notice is how much urine was produced. If the volume is low I then look at the sodium level. Many times I see a correlation between high sodium and low volume. This occurs because of peaks and valleys in salt intake.
When salt intake suddenly increases – a pizza for example – water is retained to dilute the sodium in the blood. A 24 hour urine collected on such a day will show a low volume even if you drank a lot of fluids. This is a good reason to keep salt intake low and constant.
On the other hand, when salt intake is successfully reduced, so is thirst so you have to be specially conscious about keeping up your fluids.
The best protection against stones is this combination: Low sodium and high fluid intake both at the same time.
I Have a Surprise For You
For those of you who are desperate to lose a few pounds, one of my most favorite things about eating low salt is that my tummy is flatter when I do. Eating a high salt diet will make your jeans not fit the next day and leave you feeling bloated and full.
If you weighed yourself before and after going out to dinner you will most likely find a few pounds added on the scale. It is not mostly the food, it is the water that the body must retain to dilute the extra sodium that goes into the blood as you eat it. It takes a few days to get rid of that sodium, and therefore the extra weight.
I have recently put together a private FB page called THE Kidney Stone Diet. It is a group that helps educate you on your physician prescribed treatment plans. I moderate it to keep it clinically sound. Come on over and join the discussion!
Eating a low sodium diet can be overwhelming and difficult to incorporate into your daily life. I just released a course called The Kidney Stone Prevention Course to help you understand how to implement your physician’s prescribed treatment plans.
Unfortunately Italians love their salt! It’s a (silly unhealthy) habit, according to tradition food needs to be salty to taste good! from pasta water to the sauce itself, to meat, to vegetables. I hate to think of how much salt Italians eat per day!? But this diet could be compared to the american diet which is full of packaged processed fast foods very high in sodium. I agree with Jill, if we want to reduce stones and calcifications in MSK we need to be more aware! and read every single darn label before buying and eating foods that could be contributing to MSK stones! Because a high sodium diet causes an increase in urine calcium!
Hi Celia, It is true about Italians, but the only real study of a reduced sodium diet for idiopathic hypercalciuria was done in Italy, as you know, by professor Borghi. Here in the US we have an awful lot of salt in our prepared foods, and that is indeed why Jill so emphasizes the need to cook. All the best to you and Laura, Fred
I also use some “salt substitute” (Potassium chloride) when needed.
Hi Ludwig, it is a good substitute if you like the taste and if your kidney function is normal with regard to potassium handling. Regards, Fred Coe
Hi Dr. Coe, I see that you mention that Potassium Chloride (KCl) is a good salt (NaCl) substitute if your kidney function is normal in regards to potassium handling. As a Calcium Oxalate (90% dihydrate/10%monohydrate) stone former, what urinalysis metric should I be looking at to determine if my Potassium function is normal? Additionally, would following the recommended daily dietary limit of 2300mg Sodium and 4700mg Potassium through the use of Potassium Chloride as a salt substitute be good practice or would the Chloride consumption contribute to any kidney issues?
Hi Don, Given you know your stone analysis – a very good thing, be sure you have been properly evaluated. If so the urine abnormalities will be known and you should have them treated specifically. Potassium citrate, or high potassium from foods will be as the organic anion salts not the chloride salts and these latter anions will convert to citrate that is beneficial in stone prevention. That is why KCl is less than ideal but alright if urine citrate and pH are normal and one only wants reduced sodium and something to put in food for taste – KCl as an example. Kidney function is evaluated from the serum creatinine and potassium problems from the serum potassium and bicarbonate levels – that is for your physician to be responsible for. Regards, Fred Coe
I have been told there is a difference between regular table salt and sea salt. Do they both equally add to the level of calcium in your urine or is sea salt a better choice ?
I am afraid sea salt and table salt are about the same. But I do like the texture of the sea salt! Regards, Fred
I have tried to eat a low salt diet for years. This is a very difficult thing for many people. Like you said with the people you used for the drinking water chapter, many people have occupations where they travel a lot. Eating out and getting less sodium can be done but it takes time, and practice.Many restaurants have on line info about menus, portion sizes etc . Some fast food places have the info you need posted on a wall or they have printed brochures you can ask for. It takes planning to find good places to eat and pick out items on a menu
Off the subject but related to stones
Many people on the Facebook kidney stone forum are having chronic pain
And getting the results of stone analyses that say their renal calculi are not kidney stones. You talked about the pain already, but what do these folks do? I can only quess there must be something wrong with the labs doing the testing
Anyway this is the group called
Kidney Stones Suck or something like that.
I am fortunate that I do not have chronic pain, do not pass stones all the time and know what causes my stones to form. I am also like to learn about and try to understand about health issues or medical conditions. There is so much info availabile and lots of it is antedoctol
And not scientific. I find it is essential to understand as much as you can so a patient can get good treatment. This seems to have become more difficult in the US in the last 10 years or so.
Hi Trish, I certainly agree with all of your comments. It is remarkably difficult but not impossible to control sodium intake, and very worthwhile, for stones and also bones- see the post on the site about bones and salt. The chronic pain problem is astonishing and very real. We have put up the one article about it which I imagine you read. Stone analysis labs are variable in the extreme so there are mistakes. Also patients not rarely find dried mucous on containers that feels hard like a stone and send it off – there are no crystals. I have seen the site you mention and have offered a few comments, but our facebook: Kidneystonedocs.uchicago.edu is not a member. As for information, I certainly agree. As you may have guessed I am a professor of medicine at University of Chicago and put up this site to provide rigorous information for everyone who wants it. The articles can be difficult sometimes – we do learn gradually – but they are referenced off the web to the original research publications and are at the level of the reviews and book chapters I write professionally. I myself am viewed as an expert in this field as a physician, and I am also a scientist. So this site is doing what you say but it is a slow process, articles take a long time to prepare, and many topics have not as yet been covered. They will be. Regards, Fred Coe
Thank you for this helpful article! I have a question about daily sodium intake. In the article you mentioned people that must eat out with clients at night and that they must carefully watch their salt intake at breakfast and lunch to make up for the high sodium intake at the restaurant for dinner. Is this strategy ok so long as you stay within your limit of 1500mg for the entire day or is it important to evenly space out sodium intake throughout the day? I would imagine the answer is the same as what I have been told for water intake. My urine volumes can look good but I know that there are times with my job in the restaurant industry that I get too busy to drink for hours on end and my volume is virtually non existent during those times. I know that this is not good for water intake but I wandered if the same holds true for sodium intake.
Hi Stephanie!
I am happy you asked. I am asking you to do a daily intake of 1,500. However you choose to do it is up to you. Water is trickier as you don’t want to drink all night long before bed to make up for not drinking all day. I say this because I don’t want you up all night using the bathroom and not getting your sleep.
Many clients tell me they do this and then are losing sleep. Lack of sleep is obviously not ideal. I for one am a real crab when I don’t get enough.
Thanks for writing. I am here if you need anything else.
Jill
When cooking for yourself at home, choose ingredients that taste great without salt.
This may sound self evident, but isn’t. Most people eat their food with a side of potatoes, pasta or rice; and none of these taste good unsalted. But if you chose roasted celeriac, bell peppers, carrots, red onions, parsnips or sweet potatoes instead, you’d have an excellent side dish that simply doesn’t require salting. The flavors can be varied/enhanced with the addition of herbs, spices, balsamic vinegar or fancy oils that do not contain any sodium, but these vegetables – and many more – taste great when roasted on their own. If you absolutely have to use ingredients that taste kinda bland on their own, the best spices to use are the most pungent ones; garlic, ginger, hot-paprika, cayenne pepper, chili etc.
Great advice- thanks for sharing it!
Jill
I’m having some difference of opinion with my MD about what constitutes a optimum level of sodium intake to prevent kidney stones. I’m currently on a pretty strict diet as it is – no gluten, no dairy, and no sugar. Given all this, I make almost everything that I eat, including sauces and salad dressings. I salt to taste at times at the table, but otherwise don’t add salt. I feel that this is adequate sodium restriction, am I kidding myself?
Hi Gretchen,
You are a dream! You should be very proud of your diet. Very difficult to do for sure. But I do worry you are not getting enough calcium seeing as you are not eating dairy! Let me know how you are getting calcium into your diet.
For kidney stone formers we want you to be right around 1,500 mg/day. Are you a stone former?
Best,
Jill
Wow, thank you Jill! My former nephrologist was not particularly impressed and kept after me to go no salt (Litholink test came back with elevated sodium), hence the search for someone new. Yes, I am a stone former, first one last year at 8 mm, unsure of composition since it was delivered via lithotripsy. I believe I have some calcium management issues metabolically, so I don’t take supplemental calcium. I get severe muscle cramping if I do. I eat salmon, a large variety of nuts and lots of greens (kale, etc., but no spinach) for my calcium intake. I’m 53, had a bone density test done in May 2015, which was apparently fine. Am reading lots on this website, as I feel I’m an outlier with textbook kidney stones. Hoping to get some clearer direction with his website’s information.
I also have a very strict diet due to severe food allergies. I cannot eat out or eat prepared foods. So most of my diet is made from scratch. I don’t know what my sodium intake is, but sodium in my blood and urine is at the lowest end of normal. My doctor has mentioned it several times. I’m convinced my food allergies and eating only food made at home from fresh ingredients are the reason my sodium intake is so low.
Hi Belynda,
I don’t doubt for a second that your salt is so low due to the way it is prepared and that you are eating at home.
Good for you and thanks for sharing your story.
Jill
Dairy is what caused my kidney stones to form in thw first place. Dairy also seps calcium from our bones.. I think in 2017 we aĺl know now that dark leafy grens and beana are enouh to get optimun calcijm and iron (my blood resrs are perfecr since I went plant based and I haven’t had a kidney stone in 6 years!!!) I only struģgle with low sodium, I cook almost all my family’s meals at home, plant based.
Your article about the Pat and Michelle was excellent. I’ve followed a low sodium diet, recommended by you, and
drink 130 oz of liquid a day. So far, I’ve been able to keep the stones from growing for one year now. I’ve also
had to have prolia shots for my bones, which have improved. I pray that this method continues to work in the
future for me.
I have been living with kidney stones for 19 years, and have found a low sodium diet to be very helpful in reducing my rate of calcium oxalate stone formation. My question is about the tri-citrate solution recently prescribed for me by my nephrologist to increase my urine citrate level. It is a combination of sodium citrate, potassium citrate, and citric acid. I take 45 ml per day, and it contains 1 mEq of sodium ion per ml. So the dose I take adds over 1000 mg. to my daily sodium intake? (45 mEq x 23=1035 mg) Do I have that right? After discovering your wonderful website and reading voraciously for several days, I am wondering if I should ask my doctor about switching to a citrate supplement that doesn’t contain sodium — especially since my insurance company just reclassified the tri-citrate solution from tier 1 to tier 3 and the cost increased 10-fold. May I ask what you would recommend? Many thanks for your help.
Hi Pat, You are right. The sodium citrates have never been tested in trials and probably will be inferior to potassium citrates because of the sodium. That is a guess, however and it is not sodium chloride but sodium citrate which may cause less trouble. While waiting for a trial stick with the potassium. Why did he/she add it? Were new stones forming? Is your urine citrate low = less than 400 mg/day. Check it out. Regards, Fred Coe
Hi, Dr. Coe. Yes, my last 24-hr urine showed a citrate level of 350 mg, down from 580 mg. a year earlier. No new stones recently though (fingers crossed). I just talked to my doctor and he agreed to change my Rx to an oral solution containing just potassium citrate and citric acid. He’s concerned about too much potassium, but my last K 24 was OK (75), so he has prescribed a dose containing the same amount of potassium citrate but no sodium citrate. Now let’s see if my health insurance will cooperate. Thank you so much for your advice. I am over the moon to have found your website!
Hi,
I am a Calcium Oxalate stone former. The different types of herbs that have been suggested in this article to replace salt in one’s meals (namely Tarragon, basil, rosemary, garlic) – are they low in oxalates and hence safe to consume?
Also, I have seen a product called “Mrs. Dash” which is a salt free seasoning blend that contains among others some of the herbs and spices above. Do you know if this product is safe in terms of oxalate content?
Thanks
Tom
Hi Tom, The amounts of oxalate in herbs will be small enough to ignore given one does not eat seasonings but simply use them as added flavor. Most important, if calcium intake with meals is high, as it should be, oxalate absorption falls quite a lot. The best course is 24 hour testing at intervals after important diet change so you actually know if oxalate is important in your case.
Hi Tom,
There is also a great online store called Penzey’s that have a bunch of no sodium seasonings that people rave about. You might want to add a few things to your shopping cart! As Dr. Coe said, we are not worried about spices, it is difficult to add enough that will matter.
Jill
I have cirrhosis with ascites, and am eating low sodium to shift the fluid. Kidney function is currently fine. I drink a lot of water thinking it will help move sodium out, but some online info says this can fool the body and cause serious problems including hyponatremia. How much water would you recommend in my case, if I eat 1000-1500mg sodium per day?
Hi Paul, With cirrhosis and ascites low sodium diet is reasonable. Forcing water is not good as it can cause hyponatremia. Water cannot itself remove sodium. You may also be on diuretic drugs that increase the risk of hyponatremia. In a case like yours your physicians have to give you a fluid prescription. Your condition is one I know extremely well, and understand as very individual. Ask for a number from them, and use it. Best, Fred Coe
My mother was treated for severe hyponatremia of unknown etiology about 4 months after finishing treatment for head and neck cancer. Her treatment was to take 6 grams of sodium tablets daily to normalize the serum sodium (for 2 years) and to restrict her fluid intake to 1 liter/day. We gradually decreased her dose over the course of a year and weaned her off the sodium tablets (with a normal serum sodium). Unfortunately she developed kidney stones this year (incidental finding on a surveillance CT). Could the fluid restriction and sodium tablets have caused this?
Hi Laura, The story sounds like inappropriate secretion of vasopressin incident to her cancer treatment, and the high sodium and low water intake were appropriate treatments. Her urine volume would have been exceedingly low and this indeed could have fostered stone formation. I would guess the stone was uric acid, but one can tell from the CT if it is that or calcium based. Treatment varies with this decision. Regards, Fred Coe
I was recently told to intake little to no sodium by my physician, due to peripheral edema. I get kidney stones, but haven’t had a flare up in over a year. Reading this article has brought more insight and understanding. I guess I’m just not sure still. Should I only intake 1200mg of sodium per day?
Hi Michelle, In general low sodium intake is a good idea if you do not have kidney or heart or liver disease. Usually leg swelling without any of these systemic diseases reflects venous drainage problems, and I do not know if low sodium diet will help. As I do not know why you have swelling I cannot comment on the low sodium diet. My general advice that favors it is aimed at people without significant diseases such as I mentioned, like stone formers, or people with high blood pressure. Regards, Fred Coe
Hi there, I live in the UK and there are some brands of 0% sodium salt available for people who need to reduce sodium intake. Are these ok for stone formers?
The ingredients are as follows:
Potassium Chloride, L-Lysine Monohydrochloride, Monopotassium Tartrate, Glutamic Acid, Silicon Dioxide.
Also, if you have kidney stones, how many teaspoons of salt is okay?
Many thanks
Ash
Hi Ash,
Those ingredients are not particularly harmful to stone formers. Please use less than one teaspoon of salt per day. One teaspoon is about 2,300 mg/sodium. It is best to get your sodium intake to 1,500 – 2,000 mg/day unless otherwise stated by your doctor.
Best, Jill
ok . tnk you
please explain how to calculate dietary sodium intake from a 24 hour urine collection.
Hi Joanne, the 24 hour urine sodium is your average diet sodium intake over the preceding 3 -4 days. Regards, Fred Coe
Hi, my recent ultrasound showed cortical calcification on my right kidney. I take upto 1.5 tsp of sea salt a day which has 420mg of sodium for every 1/4th tsp so about 2500mg of sodium a day. My ultrasound from 2018 had no calcification so this is a new thing. I started intaking high sodium just 2 months ago as a remedy for adrenal fatigue and severe dehydration. Sea salt really helps with the hydration part. Can high sodium cause cortical calcification? Is this the beginning of kidney stones?
Hi Deepali, Sodium salts themselves will not cause stones, but can raise urine calcium that does cause stones. Cortical calcifications are not stones, but something else. Your physicians might want to do a ultra low dose CT to figure out what those calcifications are. Regards, Fred Coe
wow. Thank you for this post. i have been eating much salt these days. I will definitely work on this. I’m so enlightened by the post.
Hi Kahn,
Salt is a hard one as it is in EVERYTHING. Look at your nutrition label to keep yourself on track!
Best, Jill
Nice post. This is good
fresh fruits, fresh seasonal vegetables, homemade butter, eggs, etc are good food with low salt in it.
Hi Sagar, I do not usually allow advertising on my site, but your material looks right and I agree that veggies and low salt are a beneficence. Fred
I think so fresh vegetables, butter, fresh fruits are good food with low salt.
My doctor had requested I have only 200mg of sodium a day after she removed my stones What is that calculated ?
Hi Tina, I suspect your physician meant 2000 mg of sodium, which is assessed by your reading food labels and keeping track. Check this with her/him. Fred
my doctor said i should minimize the way i take salt. thank you for sharing it was very helpful
Hi Francis, I presume you are a stone patient and your physician did as you say. But you also have a commercial site attached and as a rule I do not permit them. In your case I have. Fred
Recently, I have decided to limit my salt intake. Frankly speaking, it is very difficult for me to do this. All the dishes that I have eaten before, without salt, seem tasteless to me.
Hi Maximus, true – salt tastes good. But US health authorities make clear that 2300 mg/d is a tolerable upper limit, and that 1500 mg is even better. Fred
HI ! does that mean that if i want to eat a quesadilla with cheese and chicken in it and it as a total of 6oo mgs i could have that quesadilla ? then at dinner i could have a french small roll i believe its 300 i could have that too ? on weekends i choose a Friday to drink me a diet pepsi it has 65 sodium i can have that too ?
Hi John,
Just meet your goals. How you get there is your biz!
j