A 60-year-old Japanese man who was very health-conscious, didn't drink alcohol, and had normal uric acid levels nevertheless repeatedly suffered from urinary tract stones, enduring excruciating pain and even developing a massive 15mm stone. The cause of this crisis was precisely the several foods he believed were "healthy" and consumed daily.
According to President Online, 63-year-old senior public relations consultant Makoto Takahashi shared his long ordeal with urinary stones. At the end of December 2025, he was hospitalized for three days to undergo endoscopic laser lithotripsy to completely shatter and remove a massive 15mm stone lodged in his ureter. "I believed I was completely liberated from that indescribable agony." Unexpectedly, just 30 days after the surgery, bad news arrived. His attending physician, Dr. Naoki Shiga, head of urology, observed new calcifications of about 1.6mm in both of his kidneys.
Takahashi admitted that since his 40s, he had naturally passed kidney stones about eight times, never thinking much of it. However, four years ago, 7mm stones blocked both his ureters, causing lower abdominal pain and a feeling of needing to urinate without being able to pass a single drop. Doctors told him emergency surgery was necessary, as continued blockage would severely impact kidney function.
Takahashi still vividly recalls the unimaginable pain caused by the stones. He described it as sudden, knife-like pain from his flank to his back, or like his internal organs were being violently twisted, often accompanied by cold sweats and hematuria (blood in urine), and difficult to relieve even with painkillers. In the following years, he strictly followed medical advice, taking daily medication to lower uric acid and completely avoiding high-purine foods like beer and fish roe. All his health check values remained stable for years. He believed he had done everything possible to prevent recurrence.
However, stones are prone to recurrence, with over a 50% chance of recurrence within a few years. In 2025, he experienced hematuria accompanied by lower back pain, fatigue, and palpitations. Examination revealed a massive 15mm stone that had fallen from his kidney into the ureter, obstructing urine flow. He underwent surgery to remove the stone before the pain started. But to his dismay, another type of stone was already "germinating" within his kidney walls. Dr. Shiga explained that the 15mm stone removed was primarily composed of uric acid, likely formed before he started taking his medication. However, the newly discovered calcifications were most likely calcium oxalate stones.
Takahashi was shocked to find that the "high-oxalate food list" provided by Dr. Shiga perfectly matched the foods he had been deliberately consuming daily to maintain his health. He felt his "past health knowledge had been completely overturned":
The doctor explained that for the general population, these are excellent health foods. However, for people with a "stone-forming constitution," they become the "raw materials" that promote stone formation. The biggest issue is that the more health-conscious people are, the more likely they are to consume certain "beneficial" foods consistently, even excessively. This habit can inadvertently become a trap. Stone problems are no longer exclusive to those with unhealthy lifestyles. Someone like Takahashi, who diligently manages his health metrics but overlooks specific dietary risks, may be consuming "stone-forming raw materials" almost daily.
Facing this setback, Takahashi finally realized he had many misconceptions about urinary stones. First, there are many types of stones—besides uric acid stones, there are calcium oxalate stones, calcium phosphate stones, and others. Therefore, even with normal uric acid levels, consuming excessive oxalate in the diet also poses a risk of stone formation.
Second, most health information online is targeted at the "general population," but people often overlook individual differences in "personal constitution." Green tea, nuts, and chocolate are not harmful themselves; rather, they are considered health foods. The problem lies in individuals with certain constitutions continuously consuming large amounts of these "healthy foods" that are concentrated sources of specific compounds, potentially turning a wellness practice harmful. Therefore, everyone should evaluate health information more cautiously based on their own constitution and avoid blindly following trends.
