Can Alcohol Cause Kidney Stones?

Alcohol and kidney stones is something many patients ask about.  Is alcohol safe for people with kidney stones? Can alcohol cause kidney stones?  Is it okay for me to have a beer?  Most of us know that drinking a lot of fluid is good for kidney stones, so how does alcohol play into this?  Keep reading to learn more!

The Skinny: Can Alcohol Cause Kidney Stones?

In short: no.  Alcohol does not cause kidney stones. In fact, some studies have shown that drinking alcohol is actually protective against kidney stones.

One study followed 45,000 men for 6 years.  They found that people who drank 8oz of wine had a 39% reduced risk of developing kidney stones.  Beer was also associated with a 21% reduced risk.  The correlation between hard liquor and kidney stones was not as strong.(1)

A similar study followed over 81,000 women for 8 years.  This study also found that people who drank wine had a 59% reduced risk of kidney stones.  No significant effect was seen with beer or liquor.(2)

Does this mean we should all start drinking alcohol to reduce kidney stones!?  Of course not.  Alcohol is not a healthy choice for everyone and there are important factors to consider when deciding to consume alcohol.

Risks of Alcohol

No conversation about alcohol would be complete without mentioning that alcohol is a drug and is not benign.  Excessive alcohol increases risk of much more than doing silly things or saying something embarrassing.  Excess alcohol increases the risk of many medical conditions(3):

• High blood pressure and heart disease
• Cancer of the breast, mouth, throat, esophagus, liver and colon
• Weakened immune system
• Dementia and cognitive decline
• Social problems such as lost productivity and unemployment

It is important to weigh these risks when deciding to drink alcohol.  If you are at increased risk of any of these conditions, alcohol may not be the right choice for you.

There are some people who should avoid alcohol all together. For example, people who cannot control how much they drink, pregnant women, and people under 21 years of age.

It is also critical to make sure alcohol does not interact with any medications you are taking.  Ask your doctor or pharmacist if alcohol is okay to have with your medications.

Diuresis and Fluid Loss

Alcohol makes you pee.  Many of us intuitively know this from multiple trips to the restroom while having drinks with friends!  This phenomenon is called “diuresis”, and may be the mechanism of how alcohol reduces stone risk.  Increased urination causes higher urine volume.  A higher urine volume reduces saturation of troublesome solids such as calcium or oxalate.  This reduces the risk of stones.

However, failing to replace water lost during diuresis can get us in trouble.  Dehydration and subsequent reduced urine volume will cause a sharp rise in kidney stone risk.  If you do choose to drink alcohol, make sure to drink extra water to prevent dehydration.   A good rule of thumb is to drink at least 1 glass of water for every alcoholic drink you have.

Another possible reason alcohol is associated with a reduced risk of kidney stones is that alcohol is just more fluid!  Drinking a lot (around 3 liters) of fluid per day is perhaps the most important thing you can do to prevent stones.

Benefits of Alcohol and Kidney Stones

Alcohol does have some benefits other than a reduced risk of kidney stones.  Moderate consumption of red wine has been associated with reduced risk of heart disease.(4) This is likely due to the large amount of antioxidants and other bioactive components such as resveratrol and quercetin found in red wine.  These antioxidants stop harmful free radicals from harming our bodies and causing damage to our heart and vasculature.  Antioxidants can also help reduce cancer risk.

It is important to note that excessive alcohol use is associated with an increased risk of heart disease and many cancers.

Moderate alcohol consumption has also been shown to strengthen social bonds and even trigger release of endorphins.(5) It would be silly to ignore the social benefits of alcohol and the culture around drinking at sporting events, taking a trip to a beautiful vineyard or grabbing a drink with co-workers during happy hour.

What Alcohol is Best for Kidney Stones?

Wine and Kidney Stones

Wine has been shown to reduce the risk of kidney stones more than other alcoholic drinks. (1,2)  If you do choose to drink alcohol to reduce kidney stones, I would recommend wine over other alcohol for kidney stones.  Red wine has the added heart health benefits too!(4)

Beer and Kidney Stones

In men, beer did reduce the risk of kidney stones, however this benefit was not found in women. (1,2)

Beer also has a lot of purines, which break down to uric acid.  High amounts of uric acid in urine can increase crystallization of calcium kidney stones.  Also, uric acid itself can crystallize to form kidney stones.  If you form uric acid kidney stones, I strongly caution against drinking beer. People with gout should avoid high purine foods as well, including beer.

Overall, beer is not the best alcohol choice for people with kidney stones.

Liquor and Kidney Stones

For some reason, research has not shown a benefit of liquor in reducing risk of kidney stones as strongly as other alcoholic drinks did.  The research is not strong enough to recommend drinking liquor to reduce kidney stones.

Be Mindful of Sugar

A pillar of healthy eating to reduce risk of kidney stones is to avoid excess sugar.  Eating too much sugar, especially in the form of sugar sweetened drinks like soda, can cause more calcium in urine, which increases the risk of kidney stones(6,7).  Our drink choices (alcoholic or not!) can add large amounts of sugar to our diet if we aren’t careful.

Sugary mixers are common in cocktails and mixed drinks. Cola is a common mixer and contains 35g of sugar in 12 fl oz.  That is almost 9 teaspoons of sugar!  Added sugar can easily switch our answer to the question “can alcohol cause kidney stones” from a “yes” to “no”!

Here is the sugar content in common alcoholic drink mixers(8):

• Regular Cola (12 fl oz) = 35 grams
• Ginger Ale (12 fl oz) = 38 grams
• Regular Lemon Lime Soda (12 fl oz) = 33 grams
• Diet Soda (12 fl oz) = 0 grams
• Orange Juice (8 fl oz) = 24 grams
• Cranberry Juice Cocktail (8 fl oz) = 31 grams
• 100% Cranberry Juice (8 fl oz) = 7 grams
• Pineapple Juice (8 fl oz) = 29 grams
• Tonic water (8 fl oz) = 21 grams
• Simple syrup (1 fl oz) = 14 grams

Sugar can sneak into our drinks in other ways.  Take wine as an example.  Generally, red or white wine is a good low sugar choice.  A glass (6 fl oz) of dry red wine contains only 1 gram of sugar.  A glass of dry white wine has 1.7 grams.  However, sweet wines can have up to 14 grams per glass!

Serving Size is Key

As with many things in nutrition, more of a good thing does not make it better.  Excess alcohol is not a healthy choice for anyone.  If you do choose to drink, it is best to keep your portions to the recommended serving sizes(3):

• 12 fl oz beer (5% alcohol, includes most domestic or “light” beers)
• 8 fl oz malt liquor (7% alcohol, includes most “craft” or dark beers)
• 5 fl oz wine (12 % alcohol)
• 1 ½ fl oz hard liquor (80 proof, or 40% alcohol, includes liquor such as gin, rum, vodka, tequila or whiskey)

Of course, moderate alcohol consumption is more than just keeping each drink to the appropriate portion size.  It is also how many drinks you have at one time.

If you do choose to drink alcohol, the Centers for Disease Control (CDC) recommends no more than 1 drink for women and 2 drinks for men in one sitting(9).

The Verdict: Can Alcohol Cause Kidney Stones?

In short, alcohol, especially wine, is associated with a reduced risk of kidney stones.  However, this does not mean everyone should start drinking alcohol to reduce kidney stone risk.  There are many other, more impactful, dietary changes you can make to prevent kidney stones including getting in adequate fluid and calcium, consuming the right amount of protein and oxalate, as well as keeping sugar and salt to a minimum.(10)

Alcohol comes with serious risks, which must be taken into account when making the decision to drink.  If you do decide alcohol is alright for you, pay close attention to portion size and how many drinks you have at one time.  If you do this, alcohol can be part of a healthy diet for kidney stones!

Cheers & Happy Eating!

Melanie

References

1. Curhan GC, Willett WC, Rimm EB, Spiegelman D, Stampfer MJ. Prospective study of beverage use and the risk of kidney stones. Am J Epidemiol. 1996 Feb 1;143(3):240–7.
2. Curhan GC, Willett WC, Speizer FE, Stampfer MJ. Beverage Use and Risk for Kidney Stones in Women. Annals of Internal Medicine. 1998 Apr 1;128(7):534–40.
3. Drinking too much alcohol can harm your health. Learn the facts | CDC [Internet]. 2020 [cited 2020 May 22]. Available from: https://www.cdc.gov/alcohol/fact-sheets/alcohol-use.htm
4. Haseeb Sohaib, Alexander Bryce, Baranchuk Adrian. Wine and Cardiovascular Health. Circulation. 2017 Oct 10;136(15):1434–48.
5. Dunbar RIM, Launay J, Wlodarski R, Robertson C, Pearce E, Carney J, et al. Functional Benefits of (Modest) Alcohol Consumption. Adaptive Human Behavior and Physiology. 2017 Jun 1;3(2):118–33.
6. Taylor EN, Curhan GC. Fructose consumption and the risk of kidney stones. Kidney International. 2008 Jan 2;73(2):207–12.
7. Ferraro PM, Taylor EN, Gambaro G, Curhan GC. Soda and other beverages and the risk of kidney stones. Clin J Am Soc Nephrol. 2013 Aug;8(8):1389–95.
8. FoodData Central [Internet]. [cited 2020 May 22]. Available from: https://fdc.nal.usda.gov/index.html
9. Alcohol Questions and Answers | CDC [Internet]. 2020 [cited 2020 May 24]. Available from: https://www.cdc.gov/alcohol/faqs.htm
10. Han H, Segal AM, Seifter JL, Dwyer JT. Nutritional Management of Kidney Stones (Nephrolithiasis). Clin Nutr Res. 2015 Jul;4(3):137–52.