If you’re one of the 10% of adults in the United States who has passed a kidney stone, chances are you count it as one of the most painful experiences you’ve ever endured. As their name implies, kidney stones form in your kidneys. They start to develop when certain compounds in your urine become concentrated enough to form into crystals.
As urinary crystals continue to grow, they progressively evolve into hard masses, or stones. Most people don’t know they have kidney stones until one begins to travel through their urinary system. If the stone gets stuck as it tries to leave the kidney in the ureter, it can block the flow of urine and cause searing pain.
Although there’s no single underlying factor that makes some people more likely to develop kidney stones, one thing is clear: If you’ve had one kidney stone, you have a 50-50 chance of developing another one within a few years — unless you take action to prevent it.
At Robert J. Cornell, MD, PA, we believe that getting rid of problematic kidney stones is as important to your long-term health as preventing new stones from forming. With a few dietary changes, you can drastically reduce your risk of developing recurrent kidney stones.
That said, there are many kinds of kidney stones, so the type you had will determine which dietary strategies may work best for you as a preventive strategy. If your kidney stones were analyzed, Dr. Cornell may suggest specific dietary advice based on the composition of your stones.
However, the following tips are helpful for many patients.
Drink plenty of water
Perhaps the easiest and most straightforward way you can prevent kidney stones is by increasing your intake of fluids, preferably by drinking more water. That’s because staying hydrated is the best way to dilute your urine, thereby decreasing concentrations of the substances that help form kidney stones.
If you lose a lot of fluids through sweat, either because you exercise a lot or live in a hot, humid climate, you’ll have to drink enough fluids to both replace those you lost and dilute your urine.
The color of your urine can help you figure out if you’re staying well-hydrated. To prevent kidney stones, your urine should be transparent or light yellow most of the time. If your urine is yellow or cloudy, you need to drink more water.
Although all fluids count toward your fluid intake, it’s best to choose calorie-free drinks like water and limit sugary beverages, especially because consuming too much sugar can increase your chances of developing kidney stones. If you want a little flavor, try adding some fresh lemon, lime, or orange juice to your water — fruits that are naturally high in citrate have been shown to help prevent kidney stones.
Limit your sodium intake
Normally, dietary calcium that isn’t used by your bones or muscles is flushed out of your body through urine. When excess calcium isn’t washed away completely, it can combine with oxalate or phosphorous to form calcium stone.
It may come as a surprise to learn that one of the best ways to reduce excess urinary calcium isn’t by cutting your calcium intake, but by reducing the amount of sodium in your diet. That’s because high sodium levels help increase the amount of calcium that’s pulled into your urine for excretion.
Reducing your sodium intake to no more than the recommended 2,300 milligrams per day helps prevent calcium oxalate stones and calcium phosphorous stones because it decreases the overall concentration of calcium in your urine.
To get an understanding of how much sodium is in your current diet, read nutrition labels and keep track of what you eat for a week. Although cheese, processed meats, frozen foods, and canned products usually contain the highest levels, you may be surprised to learn how much sodium is hiding in just one slice of your favorite bread.
Get the recommended amount of calcium
Many people who decide to cut their calcium intake after passing a stone are surprised when their efforts don’t prevent another stone from forming. Not getting enough calcium can actually lead to kidney stone formation, however, by causing urinary oxalate levels to rise.
You also don’t want to consume too much calcium, however, as taking in more calcium than your body uses can also increase calcium levels in your urine. Consuming about 1,000 milligrams of calcium per day is recommended.
Most people can get enough calcium from their diet by eating three or four servings of calcium-rich foods each day. Plain yogurt, milk, and calcium-fortified nondairy milks are excellent sources of calcium. Although cheese can also be a good source of calcium, it also tends to be high in sodium and should therefore be limited.
Eat less animal protein
Kidney stones can also develop from uric acid, a substance that forms as your body metabolizes animal protein. Eating a diet that’s rich in beef, pork, poultry, eggs, fish, or seafood can raise uric acid levels throughout your body as well as within your urine. Having high acid levels increases your risk of developing uric acid stones as well as calcium stones.
A diet that’s rich in animal protein has another major disadvantage when it comes to preventing kidney stones, in that it reduces the amount of citrate in your urine. Citrate helps prevent the formation of kidney stones.
Depending on how much your diet affects the uric acid levels in your urine, some patients may need to cut consumption of animal protein from two or three times a day to just once a day. Discuss your protein intake with Dr. Cornell if you have questions.
Eat more fruits and vegetables
Eating fruits and vegetables may be good for just about everyone, but it’s particularly good for you if you have a history of kidney stones. That’s because including plenty of fruits and vegetables in your diet helps boost your intake of potassium, magnesium, dietary fiber, antioxidants, phytate, and citrate, all of which can help prevent the formation of kidney stones.
If your kidney stones contained oxalate, you may be asked to limit high-oxalate foods, including fruits and vegetables, or eat them with high-calcium foods. Dr. Cornell can give you individualized diet recommendations and answer any questions you may have.
To learn more about the steps you can take to avoid kidney stones, come see Dr. Cornell. Call the office today or book your appointment online any time.