Up to 10% of U.S. adults develop kidney stones at some point during their lives, and the number has been increasing in recent decades.1 This means more individuals now face excruciating pain and complications from these crystalized deposits. Kidney stones, also called nephrolithiasis, are characterized by solid clumps that form in your kidneys and cause severe flank pain, blood in your urine and nausea.
If left untreated, kidney stones sometimes block the flow of urine and lead to persistent urinary tract infections or worse, including irreversible kidney damage. Repeated bouts of kidney stones can significantly lower quality of life.
Dietary habits, particularly fat consumption, play a pivotal role in kidney stone formation,2 as elevated fatty acid intake correlates with a higher incidence of kidney stones. While conventional medicine often focuses on inadequate fluid intake alone as a top cause of kidney stones, these data make it clear that dietary fats also merit close attention.
New Insights on Dietary Fats and Kidney Stone Risk
A study published in Scientific Reports gathered data to see whether dietary intake of fat — saturated, monounsaturated and polyunsaturated — influences the odds of forming kidney stones.3 The researchers wanted to determine if any particular type of fat is strongly connected to this issue or if the overall quantity of fat matters more.
They evaluated 30,716 participants across multiple years, collecting details on what they ate, whether they had been diagnosed with kidney stones and how factors like body weight, blood sugar status and general diet contribute to stone formation.4 These participants represented a broad cross-section of the U.S. adult population, and covered a wide variety of eating habits.
The team relied on the National Health and Nutrition Examination Survey (NHANES) data set spanning 2007 to 2018, allowing for a thorough look at how fatty acid consumption compares to the presence of past or current kidney stones.
According to the results, every 10-gram daily increase in saturated fats was linked to a 22% jump in the odds of kidney stones, monounsaturated fats a 10% jump and polyunsaturated fats (PUFAs) a 21% increase.5 In other words, as you add more grams of fats to your meals, the likelihood of encountering kidney stones edges upward to varying degrees.
Subgroup analyses found no obvious “safe zone” for any type of fat. Rather, all three categories — saturated, monounsaturated and polyunsaturated — correlated with increased stone incidence.6
The study also investigated whether the ratio between different fatty acids matter. Omega-3 fats often get praise for their anti-inflammatory properties, whereas omega-6 fats increase inflammation if consumed in large amounts. And, indeed, a higher ratio of omega-6 to omega-3 was associated with a more pronounced rise in the risk of stone formation.7
These findings suggest that moderating your fat intake is a smart choice, especially if you’re prone to kidney stones or have had them before. However, rather than focusing on a single nutrient, it’s essential to consider your overall diet, as a balanced approach that accounts for multiple dietary factors will yield the best long-term results. One such factor is dietary acid load, which can influence mineral balance and urinary pH, both of which play a role in kidney stone formation.
Acid Load and the Rise of Calcium Oxalate Stones
A study published in the Journal of Renal Nutrition explored how a higher dietary acid load influences the likelihood of forming calcium oxalate stones, the most common type of kidney stone.8 Researchers conducted a case-control investigation with 430 participants to determine whether a diet rich in acid-producing foods increased the likelihood of forming these stones.
They used two validated measures, potential renal acid load (PRAL) and net endogenous acid production (NEAP), to assess each participant’s typical diet over the past year. The study involved 215 individuals newly diagnosed with calcium oxalate stones and compared them to 215 healthy controls of similar age and gender.
Using detailed food frequency questionnaires, the researchers collected insights into common eating habits, including protein sources, vegetable consumption and other dietary patterns that raise or lower acid levels in the body.
The results showed that individuals whose diets generated a higher net acid load were significantly more likely to develop calcium oxalate stones than those who ate a more alkaline or balanced diet. When they grouped participants by how acidic their diets were, they saw a clear upward trend in stone risk among those with the highest NEAP scores.
In fact, the highest tertile of NEAP — meaning the top third of participants in terms of acid load — were 88% more likely to be diagnosed with kidney stones compared to those in the lowest tertile. In practical terms, this underscores how your daily meal choices tilt the acid-base scales inside your body, contributing to a biological environment that could promote stone formation.
When you consume excessive amounts of acid-producing foods, your body tries to compensate by pulling base minerals from elsewhere or increasing the excretion of substances like calcium. That shift creates the perfect setting for crystal buildup. Mechanistically, high acid intake triggers your kidneys to excrete more acid through your urine, but that process also involves excreting more calcium.
Extra calcium in your urinary tract, along with certain other substances, combine to form crystals that eventually become kidney stones.9
Additionally, an acidic environment reduces urinary citrate, a known buffer that helps keep stone formation in check. Once those protective barriers go down, it becomes simpler for crystals to take hold. By balancing fruits, vegetables and other alkaline-forming foods against those known to cause high acid production, you maintain a healthier internal environment, which translates to a lower risk of kidney stones.
The Impact of Hydration and Oxalates on Kidney Stone Formation
A separate study published in Nutrients provides a comprehensive look at how your everyday food and drink choices shape your risk of developing kidney stones.10 This narrative review underscores that what you eat and drink plays a key role in determining whether your urine becomes too concentrated with stone-forming substances.
Inadequate fluid intake emerged as the most significant dietary risk factor for kidney stone formation. Drinking enough water helps dilute urinary minerals, reducing the likelihood of them crystallizing into stones. However, the study also highlights that not all fluids have the same effect.
While pure water and certain mineral waters support a healthier urinary balance, sugary drinks and soft drinks — especially those high in phosphoric acid — can increase the risk. These beverages introduce compounds that disrupt urine chemistry, making stone formation more likely.
Oxalate, a naturally occurring compound found in many plant foods, including spinach, rhubarb and nuts, was also highlighted. In your body, oxalate bind with calcium to form calcium oxalate crystals. According to the study, high dietary intake of oxalate increases the amount of this substance in your urine, which, when combined with calcium, creates the ideal environment for stone development.11
In simple terms, if you load your meals with oxalate-rich foods without balancing them with enough calcium, you end up with extra free oxalate that is more likely to stick to calcium and form stones.
The way you prepare your food also significantly affects its oxalate content. For example, boiling vegetables like spinach reduces their oxalate levels by leaching some of the compound into the cooking water. On the other hand, steaming preserves oxalate. So, choosing cooking methods that lower oxalate content is a proactive way to protect your kidneys.
Another important aspect covered in the study is the role of dietary calcium. Consuming enough calcium at the same time as oxalate-containing foods helps prevent stone formation. As explained by the authors, when you consume calcium-rich foods with meals high in oxalate, the calcium binds with oxalate in your stomach and intestines rather than in your urinary tract.12
This binding action reduces the amount of free oxalate that reaches your kidneys. Conversely, if you restrict your calcium intake, more oxalate remains unbound, which increases your risk of stone formation.
The paper also discusses the interplay between dietary protein, carbohydrates and oxalate metabolism. High-protein diets, especially those rich in animal proteins, increase the acid load on your body. An increased acid load alters your urine pH, making it more conducive to stone formation. Refined sugars are also linked to changes in urinary excretion patterns that favor stone development.13
In other words, your overall diet matters; imbalances in one area, such as excess sugar or protein, magnify the harmful effects of high oxalate intake.
The study further points out that individual variability plays a role in how your body handles oxalates. Not everyone absorbs oxalate at the same rate. Factors like your gut health and the presence of certain bacteria, such as Oxalobacter formigenes, influence how much dietary oxalate is absorbed into your bloodstream.14 A healthy gut flora will break down some of the oxalate before it ever reaches your kidneys, lowering your risk of stones.
A key takeaway from this analysis is that targeting the root cause of kidney stones requires a comprehensive approach. It is not enough to simply focus on one nutrient. Instead, you need to pay attention to how various dietary components interact. Drinking sufficient water dilutes the urine, while consuming the right balance of calcium with oxalate-rich foods prevents the formation of stones.
Additionally, moderating the intake of high-protein and high-sugar foods reduces the overall acid load, further stabilizing your urinary environment.15
Practical Strategies for Tackling the Underlying Causes of Kidney Stones
When you’re metabolically inflexible, your body has a diminished ability to switch between burning fuel sources, mainly carbohydrates and fats. This affects your body’s ability to produce energy, which, in turn, has a profound impact on your gut health, particularly your large intestine, as it hinders your body’s ability to maintain a low-oxygen environment in this organ.
A low-oxygen setting is essential for keeping harmful bacteria in check and nurturing beneficial bacteria like Oxalobacter formigenes, which break down oxalate crystals. Here are four steps to boost mitochondrial function, optimize your gut environment and reduce kidney stone risk. By addressing these root causes, you set up your body to fend off kidney stone formation more effectively, offering you a more sustainable and long-term solution to this common health issue.
1. Reduce linoleic acid in your diet — Cut out processed seed oils, which are high in linoleic acid (LA), a PUFA. Excessive LA intake leads to the formation of peroxynitrites, which damage your mitochondria and force your body to rely on inefficient energy production through glycolysis instead of using the electron transport chain.
Removing LA from your meals helps restore proper mitochondrial function, which in turn maximizes your cellular energy production and ultimately minimizes oxygen in your colon.
Oxalobacter formigenes thrive in a low-oxygen environment. These bacteria use specific enzymes to break down oxalate crystals into formate and carbon dioxide. The released carbon dioxide helps preserve the low-oxygen state in your gut. By supporting these microbes, you reduce the amount of free oxalate available to bind with calcium, directly addressing one of the main causes of kidney stone formation.
2. Adopt a balanced dietary approach — Ensure your overall diet supports both mitochondrial function and a healthy gut environment. In addition, it’s important to create a balanced dietary environment where protective nutrients work together. For example, pair calcium-rich foods with meals high in oxalate to bind oxalate in your gut rather than letting it reach your kidneys.
In addition, consume enough healthy carbohydrates to support cellular energy while minimizing processed foods.
3. Use antibiotics only when necessary — Antibiotics disrupt your kidney’s microbiota, reducing beneficial Lactobacillus species and promoting the growth of harmful Enterobacteriaceae, which are linked to kidney stone formation. Avoid antibiotics unless absolutely necessary and choose antibiotic-free meat from high-quality sources.
4. Drink plenty of pure water — Even though the spotlight here is on fats, don’t forget that proper hydration remains important. Drinking ample water throughout the day dilutes the substances in your urine that contribute to stone formation. Use thirst to guide you on how much water to drink daily. For better accuracy, use this visual marker — healthy urine is ideally a pale straw or light-yellow color. Dark yellow or amber-colored urine indicates dehydration.
