The drinks most likely to increase your kidney stone risk are sugar-sweetened sodas, colas, black tea, and grapefruit juice. Each raises stone risk through a different mechanism, so understanding why these beverages cause problems helps you make smarter swaps rather than just memorizing a list.
Sugar-Sweetened Sodas and Energy Drinks
Sugary drinks are among the worst choices for kidney stone prevention. An 11-year analysis of more than 28,000 adults found that people who got 25% or more of their daily calories from added sugars had an 88% higher risk of developing kidney stones compared to those who kept added sugar below 5% of daily calories. Sodas and energy drinks are the most common sources of added sugar in most diets, making them a primary target if you’re trying to lower your risk.
Fructose, the type of sugar most abundant in sweetened beverages, increases the amount of calcium, oxalate, and uric acid your kidneys excrete. All three are building blocks of the most common types of kidney stones. Even fruit-flavored drinks and sweetened iced teas that seem healthier than soda carry the same fructose load.
Cola Deserves Its Own Warning
Cola-style sodas carry a double risk. On top of their sugar content, colas are acidified with phosphoric acid rather than the citric acid used in clear sodas like lemon-lime varieties. That phosphoric acid changes your urine composition in ways that favor calcium oxalate stone formation. Lab studies in animals have shown that high phosphorus intake can cause calcium deposits to build up in the kidneys, and research on human urine confirms that cola consumption shifts urine chemistry toward stone-forming conditions.
If you drink soda at all, a citric-acid-based option like a clear carbonated drink is less risky than dark colas, though the sugar content in either is still a concern.
Black Tea Is Surprisingly High in Oxalate
Black tea is one of the most concentrated dietary sources of oxalate, and for people with kidney stones, it’s often the single biggest contributor. A study of stone patients’ diets found that regular tea and coffee together accounted for 80 to 85% of total dietary oxalate intake, with only 15 to 20% coming from all other plant foods combined. Many of these patients had chosen black tea as their go-to hydration drink, unknowingly flooding their kidneys with the exact compound their stones are made of.
Green tea contains less oxalate than black tea but is not oxalate-free. Herbal teas vary widely. If you’re a heavy tea drinker and you form calcium oxalate stones (the most common type), switching to water or a low-oxalate herbal tea can make a meaningful difference.
Coffee in Moderation Is Likely Fine
Coffee does contain some oxalate and caffeine does increase urinary calcium excretion for at least three hours after you drink it. That effect scales with dose: the more caffeine per pound of lean body mass, the more calcium you lose in urine, and your body doesn’t adapt to this loss over time. However, coffee’s oxalate content is much lower than black tea’s, and most large studies have not identified moderate coffee consumption (one to two cups a day) as a significant stone risk factor. Heavy coffee drinking, especially with added sugar, is a different story.
Grapefruit Juice Stands Apart From Other Citrus
Not all citrus juices are equal when it comes to kidney stones. Orange juice appears to be protective, with one large study of over 217,000 people showing a 12% reduction in stone risk. Grapefruit juice, on the other hand, has been linked to increased risk in multiple large studies. One prospective study of more than 45,000 men found that each daily 8-ounce serving of grapefruit juice raised stone risk by 37%. A separate study of more than 81,000 women found a 44% increase in risk with grapefruit juice consumption.
Both orange and grapefruit juice increase urinary citrate, which normally helps prevent stones, and both have alkalinizing effects on urine. But grapefruit juice also significantly raises urinary oxalate levels, which may explain why its net effect tips toward harm. Researchers have not identified a single compound in grapefruit responsible for this, but the epidemiological pattern across hundreds of thousands of people is consistent enough to warrant caution.
Alcohol: Beer vs. Liquor
Alcohol’s relationship with kidney stones depends on the type. Beer contains guanosine, a compound your body converts into uric acid. Higher beer intake increases uric acid excretion in urine, which can promote uric acid stone formation. Liquor raises urinary calcium, phosphorus, and uric acid levels. Despite these mechanisms, large population studies using NHANES data from 2007 to 2018 did not find a statistically significant increase in stone risk for moderate beer or wine drinkers compared to non-drinkers.
The bigger concern with alcohol is dehydration. Alcohol suppresses the hormone that tells your kidneys to conserve water, so you produce more dilute urine initially but end up with a net fluid loss. For someone prone to kidney stones, that dehydration can concentrate the minerals in your urine enough to trigger stone formation. If you do drink, matching each alcoholic beverage with a glass of water helps offset this effect.
Sports Drinks Are Not as Helpful as You’d Think
Sports drinks like Gatorade seem like they’d help by increasing fluid intake, but research shows they raise urinary sodium levels significantly compared to water. High sodium in your urine pulls more calcium into it, which is the raw material for the most common stone type. One study comparing Gatorade to water found that the sports drink increased urinary sodium and chloride while decreasing urinary potassium. Urinary volume and calcium levels did not improve compared to plain water, meaning you’re getting the sodium burden without any extra stone-prevention benefit.
Plain water remains the best hydration choice for stone prevention. If you need electrolytes after heavy exercise, a low-sodium option or water with a squeeze of lemon is a better fit.
What You Should Be Drinking Instead
The single most effective drink for preventing kidney stones is water. Guidelines from the American Urological Association, the American College of Physicians, and the European Association of Urology all recommend drinking enough fluid to produce at least 2 liters (about 68 ounces) of urine per day. For most people, that means drinking roughly 2.5 to 3 liters of fluid daily, since some water is lost through sweat and breathing.
Lemon water is a popular addition because lemon juice is high in citrate, which binds to calcium in urine and prevents it from forming crystals. Orange juice offers a similar benefit. Milk and other dairy drinks, perhaps counterintuitively, can help rather than hurt. Calcium from dairy binds to oxalate in your digestive tract before it ever reaches your kidneys, reducing the amount of oxalate available to form stones. The key is consuming calcium with meals so it can intercept oxalate from food.
Spreading your fluid intake throughout the day matters more than hitting a daily total all at once. Your kidneys process fluid continuously, and a steady intake keeps your urine dilute around the clock, including overnight when stone-forming minerals tend to concentrate.