Kidney stones aren’t completely preventable, but there are certain dietary changes we can make that may help reduce our risk for developing them.
A few years ago, one of my students came up to me after class one day and was complaining of pain in his lower back and vomiting. He was most concerned about the fact that he noticed there was some blood in his urine. I first told him that he needed to go to the emergency room immediately. I also mentioned that because I’m not a medical doctor, I couldn’t diagnose him, but that I did suspect one of 2 things: a kidney or urinary tract infection or kidney stones.
None of these conditions are great news for anyone, so it would be hard to root for one diagnosis over the other. But he did come back a week later and said he was diagnosed with kidney stones.
What Are Kidney Stones?
Kidney stones are actually kind of like little stones or pebbles that form in your kidneys.
You may be wondering, “How is it possible that our bodies actually form these little pebbles or stones?”
Have you ever seen real limestone or have heard what it’s made of? Limestone is, in part, made of calcium. Kidney stones are also made of calcium. A good portion of limestone is made up of calcium carbonate. The most common type of kidney stone is made of something called calcium oxalate. So you can see that stones we would find in nature, like on a stroll through the woods, are actually made of compounds very similar to kidney stones.
Where Does the Calcium and Oxolate in Calcium Oxalate Come From?
Let’s start with the calcium. Calcium is one of the most abundant minerals in the body. Our bones made mostly of calcium. Plus we get calcium from some of the foods we eat, like dairy products.
Where does oxalate came from? Oxalate is actually a natural byproduct of our metabolism. What that means is that the body naturally creates oxalate after it processes the foods we eat and uses them for energy. Having some oxalate floating around in the bloodstream is normal.
However, we don’t want that oxalate to hang around for too long, so the body tries to get rid of it. One way to get rid of oxalate is through the urine. Oxalate gets sent from the bloodstream to the kidneys so that it can get sent out of the body via the urine.
Do you know what else is found in the bloodstream and just so happens to love oxalate? You guessed it, calcium! Calcium loves attaching itself to oxalate. Actually, the feeling is mutual. Oxalate loves calcium, too. When those two find each other in the bloodstream and get together, they cause trouble. That’s because when calcium binds to oxalate, you now have this little mass or stone that forms.
And do you know where their favorite hangout is? The kidneys. These two find themselves hanging around the kidneys, find each other, and form a bond.
Luckily, there are things we can do to help reduce the chances of calcium and oxalate finding each other. Many of those are within our control!
How to Reduce the Chances of Getting Calcium Oxalate Kidney Stones Through Your Diet
First, staying hydrated with water is important. Why? We can reduce the chances of calcium and oxalate hooking up when we are adequately hydrated. It makes it a bit more difficult for calcium and oxalate to find each other that way.
Second, reducing salt or sodium intake can help. You may wonder: what the heck does salt have to do with calcium oxalate kidney stones? It turns out, consuming too much salt actually increases the amount of calcium in your kidneys. If you increase the calcium in your kidneys, it makes it more likely for those oxalates to find calcium and bind to it.
Here are 5 more diet tips for reducing your risk of developing kidney stones:
- Reduce soda consumption. Sodas are often a good source of a specific type of sugar: sucrose. Large studies have found that sucrose may increase a person’s risk for developing kidney stones.
- Substitute animal proteins like meat and chicken for vegetable proteins like beans. Beans are a good source of something called phytate. Phytate, or phytic acid, is a type of antioxidant found in most plant-based foods like beans, whole grains, nuts, and seeds. It may prevent kidney stones because it tends to block the absorption of calcium in the blood stream. If there’s less calcium in the bloodstream, then less calcium will end up in the kidneys. Less calcium in the kidneys means there’s less of a chance that oxalate will find it!
- Consume more vitamin C-rich foods. Vitamin C is found in green leafy vegetables, citrus fruits, strawberries, etc. Vitamin C may help the body remove oxalate from the blood. Speaking of things that may help remove oxalate from the blood…
- Increase consumption of magnesium-rich foods. Foods rich in magnesium include nuts and seeds. Researchers are discovering that magnesium may help block oxalate from getting into the bloodstream. Less oxalate in the bloodstream means there’s less of a chance that calcium will find it!
- Consume foods that are high in potassium. Potassium helps reduce the risk of kidney stones by binding to calcium before oxalate can find it. Potassium-rich foods include bananas, watermelon, lentils, and green leafy vegetables like spinach.
When we think about this list, the common theme is to increase consumption of plant foods! This is because they are often rich sources of the vitamins, minerals, and antioxidants that may help reduce our risk for developing kidney stones.
Oh, and as I always say, please speak with your healthcare professional before following my advice.