The experiment included 40 male C57BL/6J mice randomly assigned to four groups of 10: a control group, an untreated glyoxylic acid model group, and model groups given low- or high-dose beer. During a seven-day pretreatment phase, the intervention groups received 3 or 6 mL/kg of commercial beer by oral gavage, while control animals received equal volumes of water. During the following seven days, all model groups received 100 mg/kg glyoxylic acid daily by intraperitoneal injection, and controls received saline. The beer contained 2.9% alcohol by volume and delivered approximately 1.37 or 2.75 mg of ethanol per mouse per day. All 40 randomized animals completed the experiment, and no data points were excluded.

Untreated model mice lost weight from approximately day 6, had lower kidney wet weights and developed pale, shrunken kidneys. Their serum creatinine and blood urea nitrogen concentrations were elevated relative to controls. Beer pretreatment attenuated weight loss and moved kidney weight toward control levels, particularly at the higher dose, while reducing serum creatinine and blood urea nitrogen. These were associations within the mouse experiment rather than evidence that beer treats kidney-stone disease in patients.

Kidney histology showed extensive calcium oxalate crystal deposition, tubular dilation, glomerular atrophy, inflammatory changes and collagen accumulation in untreated model animals. Hematoxylin and eosin staining indicated fewer crystals in both beer groups. Periodic acid–Schiff staining showed less accumulation of material in renal tubules after beer intervention, although glomerular atrophy persisted. Masson’s trichrome staining showed less interstitial collagen deposition in the beer groups. Researchers also used a study-specific composite renal injury score from zero to five that incorporated crystal number, tubular obstruction, glomerular atrophy, inflammation, fibrosis and edema; histological and other image-based endpoints were designated secondary or exploratory.

Beer intervention was associated with lower immunohistochemical expression of CD44 and osteopontin in renal tubular tissue. Quantitative PCR also showed lower CD44 and Kim-1 messenger RNA in the beer groups, with the strongest attenuation generally occurring at the higher dose. CD44 and osteopontin are associated with crystal adhesion, while Kim-1 is a marker of tubular injury. The experiment did not establish that changes in these molecules directly caused the lower crystal burden, and the reduced expression could instead have reflected fewer crystals and less secondary tissue damage.

Inflammatory and antioxidant measurements also varied by dose. Untreated model mice had increased tumor necrosis factor-alpha and interleukin-1 beta messenger RNA and reduced catalase and superoxide dismutase activities. Beer partially preserved antioxidant enzyme activities, but only the high-dose group had a statistically significant reduction in tumor necrosis factor-alpha and significant recovery of catalase and superoxide dismutase activity. The change in interleukin-1 beta did not reach statistical significance. Because catalase and superoxide dismutase measure enzyme activity rather than oxidative damage directly, the evidence for attenuation of oxidative stress was indirect.

Urinary oxalate and calcium concentrations were lower in beer-treated mice than in untreated model animals. The authors considered an ethanol-driven diuretic explanation unlikely because the gavage volumes represented only about 1.2% to 4% of reported daily fluid intake, the ethanol doses were low and daily water consumption declined rather than increased during induction. Nevertheless, 24-hour urine volume and urine osmolality were not measured, nor were urinary citrate, magnesium or uric acid. The results therefore concern concentrations rather than 24-hour solute excretion, and a dilution effect cannot be excluded. The experiment also lacked non-alcoholic beer and ethanol-matched control groups, and the beer was not chemically characterized, so its effects could not be assigned to ethanol, hops-derived polyphenols or other constituents.

The clinical component was a single-centre retrospective case series involving 281 men and 134 women, with a mean age of 55.0 ± 14.2 years. Calcium oxalate monohydrate was detected in 79.0% of the 415 specimens, carbonate apatite in 54.9% and calcium oxalate dihydrate in 41.0%; mixed compositions were common, and uric acid was detected in 9.2%. The male-to-female ratio among included cases was 2.1:1. Because the study lacked a source-population denominator, these findings describe only the composition and age and sex distribution of submitted specimens and cannot establish incidence, prevalence or relative risk. Beer consumption was not recorded, so the clinical data neither support nor contradict the experimental observations.

The authors said the results should not be interpreted as a recommendation to consume beer for kidney-stone prevention. Beer carries a purine load that can increase uric acid, and excessive alcohol has established harms. Their proposed alternative was to test whether a purified, standardized, purine-free and non-alcoholic hops-derived polyphenol preparation could reproduce beneficial effects, but that remains a hypothesis. The animal model represented acute glyoxylic acid-induced crystallization rather than the full complexity of chronic human stone disease, and the study cannot establish which constituent or pathway produced the observed effects.

Subject of Research: Effects of dietary beer pretreatment on glyoxylic acid-induced calcium oxalate nephrolithiasis in mice

Article Title: Dietary beer ameliorates glyoxylic acid-induced calcium oxalate nephrolithiasis in mice

Article References: Yang, Y., Deng, X., Zhang, J., Dai, Y., Wu, X., & Liang, W. (2026). Dietary beer ameliorates glyoxylic acid-induced calcium oxalate nephrolithiasis in mice. Frontiers in Nutrition, 13, Article 1963460. https://doi.org/10.3389/fnut.2026.1963460

Image Credits: AI Generated

DOI: 10.3389/fnut.2026.1963460

Keywords: calcium oxalate, kidney stones, beer, mouse model, urolithiasis, renal injury, crystal adhesion, inflammation, oxidative stress, clinical case series, Dietary, ameliorates

The research, published in Food Chemistry: X, arrives against a sobering epidemiological backdrop. An estimated 55.8 million people were living with gout in 2020, a 150.6 percent increase in total cases since 1990, with the steepest growth concentrated in high-income regions such as North America. Men are affected roughly three times as often as women, a gap attributed largely to estrogen’s role in promoting renal excretion of urate. While aging populations contribute to the trend, the disproportionate rise in wealthy nations points toward modifiable lifestyle factors, including obesity and the consumption of purine-rich foods and drinks. Beer, brewed from nucleic-acid-rich barley malt, consistently tops the purine league table among alcoholic beverages, and epidemiological studies have linked its consumption to roughly a 1.5-fold higher gout risk compared with nondrinkers, versus a more modest 1.15-fold increase for spirits.

To measure purines across a sprawling beverage landscape, the team first had to solve an analytical problem. Traditional HPLC-UV methods for purine quantification demand harsh acid hydrolysis and multi-step enzymatic treatments that can stretch sample preparation across several days. Tandem mass spectrometry offers superior sensitivity but relies on expensive triple-quadrupole instruments that many laboratories cannot justify for routine screening. The researchers instead developed a targeted method using a single-quadrupole QDA detector operated in selected ion recording mode, coupled to an HPLC system with an ion-pairing gradient on a T3 column. By monitoring the precise mass-to-charge ratios of eight compounds, adenine, guanine, hypoxanthine, xanthine, adenosine, guanosine, cytidine and uridine, the method achieved mass-selective specificity without hydrolysis, enzymatic derivatization, or a triple-quadrupole price tag, making it well suited to quality control and large comparative studies.

With the method in hand, the team analyzed 43 commercially available and experimentally produced beverages, spanning twelve full-strength beers, four commercial non-alcoholic beers, ten experimental non-alcoholic beers brewed in-house, six sake, wine, cider, and a range of distilled and blended drinks. The results traced a clear hierarchy. Full-strength beers showed both the highest concentrations and the widest spread of total purines, from about 45.6 milligrams per liter in a light rice-adjunct lager to 223.4 milligrams per liter in a robust stout. Dark, malt-forward styles such as porters, stouts and barrel-aged rye ales clustered at the top, while lighter lagers brewed with substantial corn or rice adjuncts sat at the bottom. Guanosine dominated the purine profile of every beer, contributing roughly 41 to 68 percent of the total.

The numbers carry real dietary weight. A single 12-ounce bottle of the highest-purine stout would deliver approximately 79 milligrams of purines, nearly 20 percent of the 400 milligram daily intake limit recommended in Japan for managing hyperuricemia and gout. The researchers attribute beer’s purine richness to barley itself, whose proteins are abundant in glutamine and glycine, the amino acid precursors of the purine ring, and whose nucleic acids are liberated during malting, when germination activates nucleases that chop grain DNA and RNA into soluble nucleotides. Yeast, meanwhile, appears to do little to clean up the mess. The brewer’s yeast salvage pathways primarily assimilate purine bases rather than nucleosides, so guanosine and adenosine survive fermentation largely intact and accumulate in the finished beer.

The study’s most striking finding concerns non-alcoholic beer, a market valued at roughly 22 to 24 billion dollars and projected to nearly double within a decade. Because non-alcoholic designation is defined purely by ethanol concentration, typically below 0.5 percent by volume, it places no constraint on the non-volatile compounds that remain. Physical dealcoholization methods such as membrane filtration selectively strip ethanol while leaving dissolved solutes untouched, and the data bore this out dramatically. One membrane-processed non-alcoholic porter contained 168.5 milligrams of purines per liter, statistically indistinguishable from full-strength beers overall and comparable to its own full-strength counterpart at 182.9 milligrams per liter. Statistically, the membrane-filtered non-alcoholic beers as a group could not be separated from full-strength beers by their purine content.

Not every alcohol-removal strategy behaved the same way, however. A commercially distilled non-alcoholic lager contained just 15.3 milligrams per liter, roughly seven times lower than its full-strength counterpart, and the experimental beers brewed with a maltose-negative yeast strain, which produce minimal ethanol without any downstream alcohol removal, averaged below 50 milligrams per liter. But the researchers caution against crediting the technology alone. Because purines are non-volatile, distillation should not remove them, and the team hypothesizes that the low-purine distilled product reflects a lighter base formulation rather than the vacuum still itself. The experimental beers told the same story: when the grist was reformulated with reduced barley malt, purine levels fell regardless of the fermentation strategy used.

To probe the role of raw materials directly, the team brewed ten pilot-scale non-alcoholic beers at the university’s Center for Beverage Innovation, substituting 50 percent of the barley malt with rice, corn, cassava, millet, sorghum, wheat or unmalted barley under otherwise identical conditions. The results were consistent and quantifiable. Replacing half the malt with low-nucleic-acid adjuncts cut total purine concentrations by approximately 25 to 51 percent relative to the all-malt control, depending on the adjunct source. The most dramatic case was a beer brewed entirely from malted rice, which contained a mere 0.71 milligrams of purines per liter. Correlation analysis reinforced the mechanism: total purines tracked strongly with original extract, free amino nitrogen, and the proportion of barley malt in the grist, while the share of alternative starches correlated negatively, confirming that purine load rises and falls with malt-derived nucleic acid input.

Other beverage categories fell neatly into place. Sake, brewed from polished rice, contained between 8.5 and 40.2 milligrams per liter and displayed a strikingly different fingerprint, dominated by xanthine at 37 to 94 percent of the total rather than guanosine, a divergence the authors attribute to rice-based raw materials and the distinct fermentation biology of sake production. Red wine registered 29.7 milligrams per liter while white wine showed essentially none. Cider, malt beverages and vodka-based tea hovered near or below 2 milligrams per liter, and distilled spirits, including whiskey, tequila and soju, along with sugar-based hard seltzers, contained no detectable purines at all, since the compounds are excluded during distillation and absent from sugar washes.

The authors are careful to frame these findings as measures of dietary purine exposure rather than direct predictions of gout risk, noting that ethanol itself independently influences uric acid metabolism and that individual susceptibility, diet and clinical factors all contribute. The commercial samples represented single products rather than production batches, each experimental beer was brewed once, and the method quantified only free purine bases and nucleosides, not purines locked in nucleotides or intact nucleic acids. Still, the practical implications are clear. For brewers seeking to formulate genuinely low-purine products, the most direct lever is the grist: swap barley malt for low-protein adjuncts, or explore yeast strains and enzymes that enhance nucleoside assimilation. For consumers managing gout or hyperuricemia, the message is subtler but arguably more important: the non-alcoholic label says nothing about purines, and a dark, malt-heavy non-alcoholic stout may deliver nearly the same purine punch as the regular version on the shelf beside it.

Subject of Research: Quantification of purine derivatives in beer and fermented beverages and the effect of raw materials and dealcoholization on purine content

Article Title: Targeted analysis of purine derivatives in beer and fermented beverages using HPLC-QDA

Article References: Sen, R., Schubert, C., Rani, H., & Lafontaine, S. (2026). Targeted analysis of purine derivatives in beer and fermented beverages using HPLC-QDA. Food Chemistry: X, Article 104565. https://doi.org/10.1016/j.fochx.2026.104565

Image Credits: AI Generated

DOI: 10.1016/j.fochx.2026.104565

Keywords: purines, beer, non-alcoholic beer, gout, hyperuricemia, uric acid, barley malt, HPLC, mass spectrometry, sake, wine, food chemistry