How much water should i drink to prevent kidney stones

Monday, March 16, 2015

We know it is healthy to drink water, and that many people do not drink enough. But how much does it really matter?

Just ask anyone who ever passed a kidney stone.

Kidney stones are hard chemical deposits that can form inside kidneys, the bean-shaped organs that filter waste out of the blood and turn it into urine. They rarely grow larger than a couple millimeters, but they are extremely painful as they pass through the urinary tract and out of the body.

Nearly 9 percent of Americans have had a kidney stone, according to the National Institutes for Health, and people who get them once will probably get them again. They are a common reason for emergency hospital visits.

But we can all reduce our risk by drinking more water. We need water to live, of course, and our bodies are mostly made out of it. But water also happens to be the best way to prevent kidney stones.

Our bodies naturally create waste chemicals as byproducts of digestion, breathing and other metabolic processes. Our kidneys collect that waste, mix it with water and flush it out as urine.

The less we drink, the longer those chemicals hang around. Sometimes, when they concentrate, they form tiny solids in the kidney, often made of a calcium compound or uric acid.

A few molecules stuck together will pass unnoticed. But if a body doesn't get enough water to flush the kidneys often, that tiny solid could grow a few millimeters long.

Urine will eventually push it out of the kidney. Depending on its size, the stone will either be move slowly through the urinary tract, or it will get stuck because it's too big.

Either way, it hurts enough that someone with a stone will know that they need medical attention. Symptoms include severe pain in the belly, back or groin, blood in the urine, frequent or painful urination, and sometimes nausea.

Similar symptoms can be caused by appendicitis – which requires immediate medical attention –infection or gall bladder problems, so it's important to go to the hospital right away to find out what is wrong.

Imaging studies (such as X-rays, ultrasound or CT scans) help determine if the problem is a stone, as well as the stone's size and location in the body. Some large ones may require a procedure.

But most kidney stones are small enough to pass in a few days, anywhere from 48 hours to two weeks, and the waiting is miserable. The doctor can help manage the pain, but plenty of fluids and patience are required.

Diet and personal body chemistry can play a role in who gets kidney stones. Some people never will, but those who do so once have an increased chance of getting them again.

Cutting back on salt can help reduce the risk of forming stones, as can increasing daily intake of citric acid, found in lemons and limes. Strategies for reducing their frequency and severity should be tailored to the individual, and a urologist can help.

The most universally true way to prevent kidney stones, though, is to drink lots of water. People who have already had stones should drink between two and three liters daily.

How much water have you drunk today?

Healthy Outlook is written by the professional staff of Contra Costa Health Services, the county health department. Send questions to series coordinator Dr. David Pepper at . For more health information, go to www.cchealth.org.

If you’ve ever had a kidney stone, you surely remember it. The pain can be unbearable, coming in waves until the tiny stone passes through your urinary plumbing and out of the body. For many, kidney stones aren’t a one-time thing: in about half of people who have had one, another appears within seven years without preventive measures.

Preventing kidney stones isn’t complicated, but it does take some determination.

Kidney stones form when certain chemicals become concentrated enough in the urine to form crystals. The crystals grow into larger masses (stones), which can make their way through the urinary tract. If the stone gets stuck somewhere and blocks the flow of urine, it causes pain.

Most stones occur when calcium combines with oxalate. Stones can also form from uric acid, which is a byproduct of protein metabolism.

How to avoid kidney stones

Here are the five ways to help prevent kidney stones:

Drink plenty of water: Drinking extra water dilutes the substances in urine that lead to stones. Strive to drink enough fluids to pass 2 liters of urine a day, which is roughly eight standard 8-ounce cups. It may help to include some citrus beverages, like lemonade and orange juice. The citrate in these beverages helps block stone formation.

Eat calcium rich foods: Dietary calcium binds to oxalate in your intestines and thereby decreases the amount of oxalate that gets absorbed into the bloodstream and then excreted by the kidney. This lowers the concentration of oxalate in the urine, so there is less chance it can bind to urinary calcium. That leads to decreased risk of kidney stones.

Reduce sodium: A high-sodium diet can trigger kidney stones because it increases the amount of calcium in your urine. So, a low-sodium diet is recommended for the stone prone. Current guidelines suggest limiting total daily sodium intake to 2,300 mg. If sodium has contributed to kidney stones in the past, try to reduce your daily intake to 1,500 mg. This will also be good for your blood pressure and heart.

Limit animal protein: Eating too much animal protein, such as red meat, poultry, eggs, and seafood, boosts the level of uric acid and could lead to kidney stones. A high-protein diet also reduces levels of urinary citrate, the chemical in urine that helps prevent stones from forming. If you’re prone to stones, limit your daily meat intake to a quantity that is no bigger than a pack of playing cards. This is also a heart-healthy portion.

Avoid stone-forming foods: Beets, chocolate, spinach, rhubarb, tea, and most nuts are rich in oxalate, which can contribute to kidney stones. If you suffer from stones, your doctor may advise you to avoid these foods or to consume them in smaller amounts.

For everyone else, particular foods and drinks are unlikely to trigger kidney stones unless consumed in extremely high amounts. Some studies have shown that people who take high doses of vitamin C in the form of supplements are at slightly higher risk of kidney stones. That may be because the body converts vitamin C into oxalate.