The scary thing about kidney stones is that 50% of people who get ONE stone in their life will likely get another. Are you doing everything to prevent them?
Table of Contents
Types of kidney stones
Kidney stones are formed by a higher concentration of minerals in the kidneys, such as calcium, oxalate, and phosphorus.
Calcium oxalate and calcium phosphate
These stones can be formed from a diet high in oxalates. Some people taking high levels of vitamin D can also be at risk for developing more stones – another reason why it is important to check with your doctor before starting any new supplement order, even a vitamin!
Uric acid stones can be formed with a diet high in animal meat and proteins. Given that the American diet is generally quite excessive with its preference for animal meat, it’s not a surprise that uric acid stones are another more common stone.
These are less common but still important to note. Struvite stones are generally caused by infections, such as urinary tract infections.
This is a hereditary problem. If you have a family history of kidney stones, be sure to find out what type of stones your family members have had. And if you’ve already had one, the risk of stones developing again is higher.
Who’s at risk for developing kidney stones
There is still little evidence to help us determine exactly who is at a higher risk of developing kidney stones.
We do know that once a person does get a kidney stone, their chances of getting another stone increases by 50% if changes aren’t made!
How do I know what kidney stone I have?
The only way to know for sure is to get the stone tested. If you experience and pass a stone at home, collect it and take it to your urologist. They will be able to test the stone and provide you with more directly on your plan of care from that.
If you pass a stone and do not get it tested, it will likely lead to more fear around foods, frustration with failed attempts to change your diet, and possibly still more kidney stones.
Rules to Follow to Prevent Stones
Drinking enough water is extremely important for kidney stone prevention. By drinking enough water, we are essentially making sure the kidneys have enough fluids to create urine. And the more urine we make, the less diluted those parts of kidney stones will be. The more frequently we go to the bathroom, the more of those pieces to the kidney stone will be eliminated.
To get an estimate of how much water you need to drink, aim for about half of your weight in ounces. So for example, a 140 lb woman would aim to drink approximately 70 ounces of water per day.
Another note about hydration – it’s a marathon, not a sprint! Chugging a bottle of water here, a mug there, will not be the solution. Sip your water throughout the day to keep stable and consistent hydration.
If you have a fluid restriction prescribed by your doctor or dietitian, follow it! You may think drinking more water will help, but it will not. If you are drinking more water when your kidneys cannot filter it, you are risking your life.
Drinking more water than you need based on a fluid restriction can lead to hyponatremia (low levels of sodium in the blood), hypertension and even death. It can force your heart and kidneys to work even harder than they already are. And if you need help in controlling your fluid intake to your restriction, check out my 10 Tips to Control Fluid.
Turn your water into a stone crusher
Add citrus to your water! Lemon- or orange-infused water can help ensure you get enough citrate, which is helpful in prevention of kidney stone formation. I recommend making a pitcher of lemon water for the day and pouring from that as you need.
Keep sugars limited
So there are two sugars to think about here. First, we’ll talking about table sugar, maple syrup, agave nectar, etc. The kinds that are actually added to a food to give it more sweet taste.
The American Heart Association recommends we limit added sugars to no more than 6 teaspoons per day for women. That is equivalent to 25 grams of added sugar or 100 calories.
For men, it’s recommended they stick to 9 teaspoons per day, or 36 grams of sugar.
Fructose, the sugar that is found naturally in fruit, can also lead to more kidney stones. Fructose is also found in table sugar and high fructose corn syrup.
When sugar intake increases, it then increases the calcium in your urine. But what is also does is decrease your urine production. So what does this combination do? It increases risk of developing calcium oxalate or calcium phosphate stones!
I’m not saying don’t have fruit.
Fruit provides us with a ton of nutrients! A general rule of thumb I recommend is following a balance of 2 servings of vegetables for every serving of fruit you have.
Also, people generally benefit from having about 2 to 4 servings of fruit per day. Plenty of benefits without overdoing it and putting your kidney health at risk.
When it comes to cutting back on sugars, start with cutting out added sugars before you reign in on fresh, frozen or even canned or dried fruit.
Cut out salt to prevent most stones
Think you’re already on a low-sodium diet? Check again.
I had a patient in dialysis that struggled not only with his fluids (he drank more water than he needed for his treatments), but his diet was high in sodium. Because he could not drink more water to help eliminate the stones, he had to be extremely careful with his sodium intake.
The average American diet is close to double the American Heart Association’s recommended salt guideline of less than 2,300 mg sodium daily.
My number one tip for cutting salt- don’t go out to eat. It’s a tough thing to do, but salt is everywhere in fast foods and restaurants. If you are struggling with going cold-turkey, check out my article about tasty fast foods that are okay for kidney disease.
Get the right amount of calcium
Calcium oxalate stones are the most common type of kidney stones. Some people believe that by avoiding calcium, they will lower their risk of developing kidney stones. It’s actually the opposite- not getting enough calcium in your diet can lead to more frequent kidney stones.
Plant-based sources of calcium include tofu, calcium-fortified breads and cereals, broccoli, seaweed, and beans. However the calcium in these foods may be already bound to oxalates and less available.
Thinking of skipping straight to calcium supplements? Check with your doctor or dietitian first – these can actually increase your risk of kidney stones if taken excessively. If you are advised to take a calcium supplement, be sure to take as directed!
Plant-based milks may have supplemental calcium added, but this is similar to taking a calcium supplement.
Adding dairy products may be helpful to get the right amount of calcium, which is possible. Working with a dietitian can help give you support and guidance on getting the right amounts.
Avoid high-oxalate foods
When you do have foods that are higher in oxalate, pairing them with calcium-rich foods can help! By eating these foods together, it will lower the chances of stone formation since they will bind to each other before reaching the kidneys.
The general goal in following a low-oxalate diet is to stick to 100-200mg oxalate per day.
Looking for a helpful tool in determining the oxalate content of foods? Check out this searchable oxalate database from Jill Harris, RN.
Don’t focus on eliminating all foods with oxalates. It may be helpful to at least avoid the ones with the highest amounts – like spinach and almonds – but the goal here is not to cut out as many foods (and nutrients!) as possible.
And by that, I’m saying eat less animal meat. Animal proteins are more acidic compared to plant proteins, so they can lead to higher odds of developing calcium oxalate and uric acid kidney stones.
Animal meats also are generally high in purines, which can lead to formation of uric acid stones when consumed in high amounts.
Skip the vitamin C
If you’re thinking back to the citrus-infused water, remember, it’s about the citrate – not the vitamin C.
The body converts vitamin C into oxalate. So if you have an excessive amount of vitamin C, you are more likely to generate a higher amount of oxalates in your system. This can lead to more frequent stone formation.
Supplementing with vitamin C is generally not recommended for those with kidney issues unless medically necessary.
Ask your doctor about medications to help
Your urologist or nephrologist may be able to prescribe you medication to further help prevent the formation of stones.
Potassium citrate may be prescribed to help prevent stone formation. Keep in mind this medication does include potassium, but your doctor is aware of this. As always, keep an eye on your potassium in your blood test results and be sure to communicate any concerns with your prescribing physician.
Thiazide diuretics may be prescribed to help lower the kidneys remove calcium from the urine and put back into the blood.
Allopurinol is generally prescribed for gout and formation of uric acid kidney stones by lowering the level of uric acid in the blood.
Acetohydroxamic acid (AHA) is generally used for those that develop struvite stones.
Cystine-binding thiol may be prescribed if you have cystine stones.
As with all prescriptions, be sure to take as ordered and if any change needs to be made – talk with your prescribing doctor.
Watch the Conversation with DadviceTV and Jen about Kidney Stones!
DISCLAIMER This information is not a tool for self-diagnosis or a substitute for professional medical advice. It is not to be used or relied on for that purpose. Please talk to your urologist or health care provider about your health concerns. Always consult a health care provider before you start or stop any treatments, including medications.