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Objectives: Kidney stone disease (KSD) has a strong association with diet metabolic syndrome. This review aims at exploring the lithogenic risk posed by the current most popular diets. Our approach was to search for the effect of each diet type on the major urinary risk factors, to try to draw conclusions regarding the association of a specific diet type and KSD., Methods: This systematic review searched for the available literature exploring the association between the existing popular fad diets and KSD. Articles in English, French and Spanish were included, without restriction of the search period with the final search done in August 2021., Results: Total number of studies and studies for each diet type was as follows: 22 articles for the low carbohydrate diet, 20 articles for high protein diets, 26 articles for vegetarian and vegan diets. There exists a substantial variability in different low carbohydrate and high protein diets, and considerable overlap between modern popular fad diets. High carbohydrate intake might increase urine uric acid, calcium and oxalate levels. High protein diets increase urine calcium and uric acid and lower urine pH and citrate. Consumption of fruits and vegetables increases the urinary volume and urinary citrate. In vegan diets, sufficient daily calcium intake is important to avoid possible secondary hyperoxaluria., Conclusions: Few studies evaluated the direct relationship between modern fad diets and KSD. In general, the reduction of carbohydrate in the diet, and counterbalancing protein rich diets with sufficient intake of fruits and vegetables, seem to play a protective role against KSD formation. Maintaining sufficient calcium intake in vegan and vegetarian diets is important. Additional research is needed to directly evaluate the link between KSD and each diet type.

To explore the relationship between citrus fruit juices (oranges, grapefruits, and lemonades) and kidney stone disease (KSD)., Methods: A systematic review was performed using the Medline, EMBASE, and Scopus databases, in concordance with the PRISMA checklist for all English, French, and Spanish language studies regarding the consumption of citrus fruit juices and the relationship to urinary stone disease. The main outcome of interest was the association of citrus fruit juices with KSD., Results: Thirteen articles met the criteria for inclusion in the final review. Three large epidemiological studies found that grapefruit juice was a risk factor for stone formation, while orange juice did not increase the risk for KSD. Ten small prospective clinical studies found that orange, grapefruit, and lemon juices all increased urinary citrate levels. Only orange and grapefruit juices had an alkalinizing effect and while lemon juice has a protective effect by raising urinary citrate levels, it lacked a significant alkalinizing effect on urine pH. Orange juice and grapefruit juices significantly increased urinary oxalate levels, while orange juice also had a high carbohydrate content., Conclusion: While orange juice seems to play a protective role against stone formation, grapefruit was found to raise the risk of KSD in epidemiological studies but had a protective role in smaller clinical studies. Lemon juice had a smaller protective role than orange juice. Larger amounts of, as well as more accurate, data is needed before recommendations can be made and a high carbohydrate content in these juices needs to be taken into consideration.

Mercury an important therapeutic substance in Tibetan Medicine undergoes complex "detoxification" prior to inclusion in multi-ingredient formulas. In an initial cross-sectional study, patients taking Tibetan Medicine for various conditions were evaluated for mercury toxicity. Two groups were identified: Group 1, patients taking " Tsothel" the most important detoxified mercury preparation and Group 2, patients taking other mercury preparations or mercury free Tibetan Medicine. Atomic fluorescence spectrometry of Tibetan Medicine showed mercury consumption 130 µg/kg/day (Group 1) and 30 µg/kg/day (Group 2) ( P ≤ 0.001), levels above EPA (RfDs) suggested threshold (0.3 µg/kg /day) for oral chronic exposure. Mean duration of Tibetan Medicine treatment was 9 ± 17 months (range 3-116) (Group 1) and 5 ± 1.96 months (range 1-114) (Group 2) (NS) with cumulative days of mercury containing Tibetan Medicine, 764 days ± 1214 (range 135-7330) vs. 103 days ± 111 (range 0-426), respectively ( P ≤ 0.001). Comparison of treatment groups with healthy referents (Group 3) not taking Tibetan Medicine showed no significant differences in prevalence of 23 non-specific symptoms of mercury toxicity, abnormal neurological, cardiovascular and dental findings and no correlation with mercury exposure variables; consumption, cumulative treatment days, blood/ urine Hg. Liver and renal function tests in treatment groups were not significantly increased compared to referents, with mean urine Beta 2 Microglobulin within the normal range and not significantly associated with Hg exposure variables after correcting for confounding variables. Neurocognitive testing showed no significant intergroup differences for Wechsler Memory Scale, Grooved Pegboard, Visual Retention, but Group1 scores were better for Mini-Mental, Brief Word Learning, Verbal Fluency after correcting for confounding variables. These results suggest mercury containing Tibetan Medicine does not have appreciable adverse effects and may exert a possible beneficial effect on neurocognitive function. Since evidence of mercury as a toxic heavy metal, however, is well known, further analysis of literature on mercury use in other Asian traditional systems is highly suggested prior to further studies.