Sugary sodas top the list of drinks that can damage your kidneys, but they’re far from the only ones. Energy drinks, excessive alcohol, and even diet sodas have all been linked to declining kidney function. The specific ways each drink causes harm vary, from driving up uric acid to depositing calcium phosphate crystals in kidney tissue. Here’s what the evidence shows for each one.
Sugar-Sweetened Sodas and Fruit Drinks
Of all dietary risk factors studied between 1990 and 2021, a diet high in sugar-sweetened beverages was associated with the most substantial increase in chronic kidney disease burden worldwide. People who regularly consume sugary drinks have about 1.3 times the risk of developing chronic kidney disease compared to those who rarely drink them.
The main culprit is fructose, which is found in both high-fructose corn syrup and table sugar. When your liver processes fructose, it burns through cellular energy stores so rapidly that a waste product, uric acid, builds up. Unlike glucose, fructose metabolism has no built-in brake system, so the more you consume, the more uric acid your body generates. That excess uric acid damages the small blood vessels feeding your kidneys and raises blood pressure inside the filtering units themselves.
Fructose also reaches your kidneys directly. It gets filtered into urine and absorbed by cells in the kidney’s tubules, where it triggers the same energy-depleting reaction, producing uric acid right inside kidney tissue. This causes localized inflammation and oxidative stress, essentially a slow burn of damage to the cells responsible for filtering your blood.
Cola Drinks and Phosphoric Acid
Cola-type sodas carry an additional risk beyond their sugar content. They’re acidified with phosphoric acid rather than the citric acid used in most non-cola carbonated drinks, and that distinction matters for your kidneys. Phosphoric acid promotes urinary changes that make kidney stones more likely, particularly calcium oxalate stones.
In a randomized trial of men with a history of kidney stones, those who continued drinking phosphoric acid-containing soft drinks had a higher rate of stone recurrence than those who switched to citric acid beverages. High-phosphorus diets can also lead to calcium phosphate deposits forming directly in kidney tissue, a condition called nephrocalcinosis. While the phosphorus dose from a single cola is far lower than what causes acute damage, long-term daily consumption adds up, especially if your kidneys are already working below full capacity.
Diet Soda
Switching to diet soda doesn’t necessarily protect your kidneys. A study tracking women over 11 years found that drinking two or more servings of artificially sweetened soda per day was associated with twice the odds of significant kidney function decline compared to drinking less than two per day. Women in this group were also more than twice as likely to lose kidney filtering capacity at a rate of 3 or more milliliters per minute each year, a pace that can lead to meaningful impairment over a decade.
Below two servings per day, no increased risk was observed. The exact mechanism isn’t fully understood, but the association held even after adjusting for age, weight, blood pressure, diabetes, and other factors that affect kidney health.
Energy Drinks
Energy drinks combine high doses of caffeine, taurine, sugar, and preservatives in a way that can overwhelm kidney function when consumed in large quantities. Case reports of acute kidney injury have been documented in people drinking 2 liters or more per day for extended periods. In one case, a 21-year-old man developed kidney failure after consuming 2 liters daily for a month. The product contained 150 milligrams per liter of caffeine and 800 milligrams per liter of taurine.
Animal studies have shown that the combination of caffeine and taurine can cause direct structural damage to kidney tissue, including bleeding and degeneration of the tiny filtering structures. Preservatives like sodium benzoate may also play a role, though their contribution is harder to isolate. Nearly all reported cases of energy drink-related kidney injury involved consumption of 2 liters or more daily over consecutive days, so occasional use at normal serving sizes poses far less risk.
Alcohol
Heavy alcohol consumption is consistently linked to chronic kidney disease, particularly in young and middle-aged men. Drinking four or more servings per day is associated with significantly higher odds of kidney disease compared to abstaining. For women, the threshold appears lower: intake above 280 grams of alcohol per week (roughly 20 standard drinks) has been tied to elevated risk.
Alcohol damages kidneys through several overlapping pathways. It overstimulates the hormonal system that controls blood pressure and fluid balance, leading to high pressure inside the kidney’s filtering units. At the same time, chronic drinking reduces levels of a protective compound that normally dilates blood vessels feeding the kidneys and suppresses inflammation. The combined effect is abnormal blood flow through the kidneys, gradual destruction of the filtering structures, and progressive loss of function. Heavy drinking also promotes a condition called renal hyperfiltration, where the kidneys work harder than normal in the short term but wear out faster over the long term.
Grapefruit and Orange Juice
Fruit juice is often seen as a healthy choice, but certain juices can increase kidney stone risk. Orange juice and grapefruit juice both significantly raise urinary oxalate levels. Oxalate binds with calcium in the kidneys to form the most common type of kidney stone. One large study found that each 240-milliliter serving of grapefruit juice consumed daily increased the risk of stone formation by 37% in men.
Orange juice also comes with a high carbohydrate load and does not reduce calcium excretion the way some other citrus drinks do. If you’re prone to kidney stones, European and American urology guidelines recommend moderating oxalate intake and keeping orange juice consumption to around 200 milliliters per day or less. Lemon juice, by contrast, is high in citrate and low in oxalate, making it a better option for stone prevention.
Sports and Electrolyte Drinks
Sports drinks are designed for athletes losing fluids through heavy exercise, not for casual sipping throughout the day. Many contain 250 milligrams or more of sodium per serving, along with potassium, magnesium, and chloride. For healthy people who aren’t exercising intensely, that extra sodium adds to your daily intake without any real benefit, and excess sodium forces your kidneys to work harder to maintain fluid balance.
For anyone with existing kidney problems or high blood pressure, the sodium and potassium loads in sports drinks can be genuinely dangerous. Damaged kidneys struggle to excrete excess potassium, and elevated blood potassium levels can cause serious heart rhythm problems. If you’re exercising hard enough to sweat heavily for more than an hour, a sports drink makes sense. For everyday hydration, water is the safer and more effective choice.
What About Coffee and Tea?
Caffeine causes a short-term spike in blood pressure, which is why it sometimes gets flagged as a kidney concern. But the Mayo Clinic notes that people who drink caffeine regularly develop a tolerance, and habitual coffee or tea consumption is not linked to a higher risk of high blood pressure. Up to 400 milligrams of caffeine per day (roughly four 8-ounce cups of brewed coffee) is considered safe for most adults without hypertension.
Black tea does contain oxalates, so people with a history of calcium oxalate kidney stones may want to limit intake. Green tea is lower in oxalates and generally considered less of a concern. Plain coffee and tea, without added sugar or cream, are not associated with kidney disease progression in people with healthy kidneys.
The Drinks That Help
Water remains the single best drink for kidney health. Staying well-hydrated dilutes the substances in urine that lead to stones, and it helps your kidneys flush waste efficiently. Urology guidelines recommend drinking enough fluid to produce at least 2 to 2.5 liters of urine per day, which typically means drinking somewhat more than that in total fluid.
Milk, despite old assumptions that its calcium content promotes stones, actually appears protective. A large analysis of U.S. adults found that higher milk consumption was associated with a 10% lower risk of kidney stones overall, and women who drank milk frequently had a 29% lower risk compared to women who never drank it. The calcium in milk binds oxalate in your digestive tract before it ever reaches your kidneys, reducing the raw material for stone formation. Low-fat milk consumed daily is now actively recommended as a strategy to lower kidney stone risk.