If you haven’t had a kidney stone, thank your lucky stars. You probably know someone who has and, similarly, you probably know they can be incredibly painful. More than 300,000 Americans a year go to the emergency room for kidney stones and an additional 1 million people visit their doctor for them, according to the National Institute of Diabetes and Digestive and Kidney Diseases. One in five men and one in 10 women will develop kidney stones in their lifetime. Risk factors include a genetic predisposition to kidney stones, overactive parathyroid glands, gout and kidney diseases.
So how do these stones develop? Kidney stones form when substances in your urine — such as uric acid, calcium, oxalate and phosphorous — become concentrated. There are four major types of kidney stones: calcium stones (the most common), uric acid stones (common among people with gout), struvite stones (resulting from chronic kidney infections) and cystine stones (when cystine leaks through the kidneys and into the urine).
Doctors recommend drinking at least eight cups of fluids per day to help prevent kidney stones. The more you drink, the less concentrated the substances are in your urine. But are all fluids created equal? Water is best, but studies show that alcohol can have both positive and negative effects on your chances of developing kidney stones. Here are five facts to keep in mind about the effects of alcohol on kidney stones:
1. Purines can wreak havoc
People with gout know that alcohol, particularly beer and grain alcohol, are high in a substance called purines. Uric acid is produced when the body breaks down purines. Normally, uric acid is excreted in the urine, but when you consume too many purines, uric acid can accumulate and deposit in your joints as gout or in your kidneys as uric acid kidney stones.
2. Dehydration equals concentration
“Alcohol and caffeine have a diuretic effect, causing the kidneys to make more urine,” Dr. Howard LeWine writes for MSN’s Healthy Living. “This is helpful for preventing kidney stones. But if you are drinking too much alcohol or caffeine and not enough water or other liquids, you can dehydrate.” Dehydration leads to more concentrated urine, allowing substances to collect into kidney stones.
3. Weight can lead to stones
We all know alcohol can lead to weight gain. Weight gain, it turns out, can also lead to kidney stones. A 2010 study at Johns Hopkins University concluded that obesity doubles a person’s chances for developing kidney stones. The researchers speculate metabolic and hormonal changes in obese patients increase their risk for kidney stones, as well as diet. Continued research is being conducted to specifically look at the metabolic and hormonal causes.
4. Excess is not the answer
Chronic drinkers can do lasting and irreversible damage to their kidneys, often in conjunction with liver disease. Long term effects can include a disruption in the body’s acid-base balance, decreased sodium excretion and difficulty producing urine, conditions which may lead to the development of kidney stones.
5. Moderate levels can help
A 2013 study in the Clinical Journal of the American Society of Nephrology indicates that people who drink a beer a day have a 41 percent lower chance of developing kidney stones; wine drinkers have a 33 percent lower chance of developing them (this may be because alcohol has a diuretic effect). Other drinks seem to help, too. Coffee leads to a 26-percent lower risk, orange juice a 12 percent lower risk and tea an 11 percent lower risk. People who consume daily sugary drinks, on the other hand, have a 23-percent higher chance of getting kidney stones.
The key to avoiding kidney stones is moderation and hydration. The occasional glass of wine or beer won’t mean you’re going to start producing stones, but you should balance your alcohol intake with plenty of hydrating substances like water, decaffeinated tea and diluted juices.
Speak with a doctor immediately if you begin to suspect symptoms of a kidney stone. Use iTriage to locate a provider in your area.