How to Eat a High Calcium Low Sodium Diet

Many patients assume that they are forming calcium stones and should therefore limit their calcium intake. That assumption could not be more wrong. Low calcium diet won’t stop your stones and may even increase your risk. Lets not forget that our bones are in desperate need of calcium to avoid osteopenia and osteoporosis.

But, many of the best foods for calcium are also high in sodium, and sodium raises urine calcium loss and stone risk.

Now what?

How Much Calcium do We Need?

The National Institutes of Health tells us age matters. Nineteen to fifty year old male or female need 1,000 mg of calcium a day. Fifty one to seventy year olds need 1,000 mg for males and 1,200 mg for females. Those above seventy one need 1,200 mg, both sexes.

We all know that much of our calcium comes from diary products. But did you know that dairy products are very high in sodium?

When we eat a high calcium food that is also high in sodium the sodium can undo the benefits of the calcium by raising urine calcium losses. This is especially true for stone formers with idiopathic hypercalciuria whose urine calcium is much more sensitive to sodium than in normal people.

So we need to search for dairy products that are lower in sodium than usual.

We also have to find what else there is because not everyone can tolerate dairy products. This means fruits and vegetables, and they may contain oxalate.

How to Read Food Labels for Calcium

All food labels are based on a 2000 calorie per day diet. Calcium is given to us in the form of a percentage.

How do we figure out how much we are getting per serving?

Take a look at the featured picture. It shows Friendship Dairy cottage cheese no salt added.

This is a great product for high calcium and low salt. On the label it tells us that per serving you will receive 10% of your daily value for calcium.

How do we convert this to milligrams?

Since we know that every food label is based upon a 2000 calorie per day diet, and gives the percent of the recommended 1,000 mg of calcium for that diet, we can just put a 0 at the end of the percent. So 10 percent is 100 mg of calcium. In this case a serving size is half of a cup. Eat more or less and the calcium from the product will vary.

Eating a low sodium, high calcium 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.


We are going to continue with the example of the cottage cheese

breakstone reduced sdium cottage cheese

The low salt version of Friendship Cottage Cheese has only 60 mg of sodium per serving. The regular Friendship cottage cheese contains 260 mg/serving. This is a great sodium savings in that the ideal intake of sodium is only 1,500 mg daily.

As a contrast take a look at this product.

The label, which does not show, says a serving contains 15% of daily requirement which is 150 mg of calcium. But the sodium in that serving is 290 mg!

The Trouble with Food Labels

These Friendship and Breakstone cottage cheese products are two excellent examples of how difficult it is to distinguish between really low sodium and rather high sodium products.

The 30% less sodium label is correct, but it is 30% less than a lot of sodium. The Friendship label tells you there is no salt added, which is also true.

But the actual sodium amounts are what you want to look at. They have to be accurate by law and they are.

You have to notice the small subtleties in all food labelling. It is definitely worth the time if you want to keep sodium low while getting adequate calcium.

How to Shop for Low Sodium Dairy Products

We have to become experts at reading food labels. Don’t pay mind to the front of the package. The nutrition label is the only thing you need to look at. You want the highest calcium for the lowest sodium, and the only way to get it is by looking at the label. Sometimes this may require you to look at several brands. You may have to stop using your favorite brand.

In the beginning of this process it may seem this is a daunting task.

But before long you will become quite efficient and even a food label expert.

No Food Label?

Many of  you will shop at the deli counter or prepared food section, or eat in a restaurant. You will just have to remember that certain dairy products have a lot of salt – like cheese – and find the low sodium alternatives. When you are asking the deli counter person to cut you some cheese or the waiter to bring you a fancy cheese plate you have to ask for the low sodium varieties if there are any.

What if You Can’t or Won’t Eat Dairy Products

If you won’t maybe you should take a look at our list and reconsider. The list is ordered by how much calcium is in a serving. Dairy products win by a big margin. So if you possibly can use them, use them.

The remaining options are fruits, vegetables, fish, and supplemented foods. We have consulted the usda data laboratory charts for calcium and sodium, and our own oxalate lists to give you what we can find with modest oxalate and a high calcium per sodium ratio. We have redacted from the immense usda lists our list of the best calcium to sodium bargains adjusting for oxalate from our oxalate lists.

The list is what we think will be most useful to you. Below we highlight a few foods in each category that we specially like.

Fruits and Juices

Fruits have very little sodium when raw and fresh, so it is all about their calcium content.

The most calcium in this category will be found in one cup of calcium fortified orange juice – 366 mg. Calcium supplemented grapefruit juice gives 350 mg of calcium in 8 ounces. The oxalate in grapefruit is modest and will fit into most diets. Apple juice fortified with calcium has little oxalate and is a good choice. We emphasize that these are calcium supplemented juices, otherwise they will not do.

Some useful foods have too little calcium to make our list but are good, Pineapple juice, 6 ounces gives 84 mg of calcium. Plums and apricots are very low in oxalate and a cup gives about 70 mg of calcium. Blueberries and pears are low in oxalate and give about 60 mg for a cup. Peaches give about 50 mg of calcium/cup.

Fish and Seafood

Sardines, no salt added, have about 150 mg of calcium and 50 mg of sodium in a serving. Three ounces of canned salmon provides 212 mg of calcium and 64 mg of sodium. Most other fish, even fresh, have about 80 mg of sodium for every 120 mg of calcium, which is not a great ratio. Crustacea have very high sodium levels even when fresh.


From the list, here are a few highlights.

Kale, frozen, boiled, and drained without salt has 179 mg of calcium, 20 mg of sodium and little oxalate – a great bargain. Mustard greens, frozen, are low in oxalate and have 152 mg of calcium with 38 mg of sodium. Chinese cabbage (bok choy) has 158 mg of calcium and 58 mg sodium in 1 cup, and very little oxalate.

Several foods are too low to make the list but are tasty and can be used. Winter squash gives 80 mg calcium and 8 mg sodium in one cup. Raw onions have little oxalate but 72 mg of calcium and 8 mg of sodium in a cup. Cowpeas, if you find them, also known as black eye peas,  have 184 mg of calcium, and 27 mg sodium in a cup.

So Now What?

You may not like what I am about to say but that’s not going to stop me from saying it. For people who choose to avoid dairy products by choice or because of lactose intolerance or food allergy, it is difficult to get enough calcium into the diet without an excess of sodium and in the case of fruits and vegetables too much oxalate. There is one usable alternative milk and yogurt product: coconut. Soy and almonds are too high in oxalate.

That leaves supplements. We have already mentioned calcium supplemented juices. Pill supplements can be used – check with your physicians – but only with substantial meals. Taken without food they can raise urine calcium a lot and it is not clear that bone cells will use the calcium. So used improperly supplements can increase stone risk. With meals, supplements can and do lower urine oxalate.

Eating a low sodium, high calcium 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.


113 Responses to “How to Eat a High Calcium Low Sodium Diet”

  1. Lisa

    Dr. Coe,
    What are your thoughts on Vitamin D? I’ve wondered if taking supplements is hype or needed. It seems like 15-20 years ago no one took Vitamin D and now many do. If someones Vit D 1,25 is fine and their Vit D 25 OH is on the lower side of normal or even a little under the normal range but the 1,25 is normal do they really need supplements and what role if any does Vitamin D have on stones other than you need Vit D for calcium absorption? Thank you!

    • Fredric Coe, MD

      Hi Lisa, 25D is the storage form of vitamin D and itself active via the same vitamin D receptor as 1,25D. It is that the latter has 1000x the effect of the former and is present at about 1000 fold lower concentration. Both matter. So you should take 25D sufficient to maintain a normal blood 25D level. That level of 25D supplement is not known to cause kidney stones. Regards, Fred Coe

  2. Ed

    Hello Dr Fredric Coe, thank you in advance for considering my “question.”
    Blood in urine – CT scan showed 6 mm stone in Left ureter– removed on Jan 17,’22 via cystoscopy, ureteroscopy, with lithotripsy using ho:yag laser ( 2 hr surgery )– Calcium oxalate stone; Urine collection 2 weeks later showed low citrate – Dr prescribed Potassium Citrate ( 1080 mg 3 times a day with meal & 1200 mg Ca ); blood in urine & ct scan showed 12mm stone in right kidney pelvis – on May 2, ’22, another surgery, cystoscopy, ureteroscopy, with lithotripsy using ho:yag laser ( 2.5 hr surgery) — found 12mm stone embedded & several other stones in area — Calcium Oxalate stones again.
    Discontinued Ca supplement; and now reviewing what has happened to me —
    On 1st Urine collection,Supersaturation CaOx 3.6, supersaturation CaP 0.47 , urine calcium 131, urine oxalate 44, citrate 290, urine uric acid 0.543, urine pH 6.348.
    On 2nd Urine collection,Supersaturation CaOx 2.5, supersaturation CaP 1.63 , urine calcium 289, urine oxalate 28, citrate 795, urine uric acid 0.630, urine pH 7.246 .
    I am concerned about now forming calcium phosphate stones… I am now watching Protein, Sugar, & Salt intake as Jill Harris, LPN suggests and as I have seen in her Kidney Stone Prevention course videos that I signed up on Sept 12,’22- my Water intake is 84 – 112 oz water / day. On september 20,’22 I Asked for another urine collection and a fasting blood draw to check my potassium & to see status of urine –An order was only given for a fasting blood draw — BMP w/GFR–all results were good on this basic metabolic panel.
    Thinking I may not need as much potassium citrate extended release ? Calcium supplements may have caused high Ca in 2nd urine collection. I am going to push for another urine collection and fasting blood test. Any advice or insight appreciated. Wish I could start over… but life moves forward, not backwards.
    Thank you, Ed

    • Fredric L Coe, MD

      Hi Ed, WHen the first stone was removed, is there reason to believe the other stone(s) were not already present? Your urine SS for CaOx are low, and these stones do not grow very fast. From Jan to May it is not likely that a 12 mm stone formed as well as several other stones. You can read the CT report from Jan and also ask your physician. Your urine calcium was low at 131 and frankly only a bit increased the second time. You indicate the second stone was calcium oxalate so calcium phosphate was not an issue. You seem to illustrate one key issue in this disease, counting stones. While I do not favor calcium supplements and much prefer calcium from foods, it seems a remote idea the second stone(s) were new. Regards, Fred Coe


Leave a Reply