Kidney Stones
IP-6
IP-6 (inositol hexaphosphate, also called phytic acid) reduces urinary calcium levels and may reduce the risk of forming a kidney stone.Dose:
120 mg dailyIP-6IP-6 (inositol hexaphosphate, also called phytic acid) reduces urinary calcium levels and may reduce the risk of forming a kidney stone.1 In one trial, 120 mg per day of IP-6 for 15 days significantly reduced the formation of calcium oxalate crystals in the urine of people with a history of kidney stone formation.2
Chondroitin Sulfate
Chondroitin sulfate may help reduce the risk of kidney stone formation. One trial found that glycosamionoglycans significantly lowered urinary oxalate levels, which reduces the risk of stone formation.Dose:
Refer to label instructionsChondroitin SulfateChondroitin sulfate may play a role in reducing the risk of kidney stone formation. One trial found 60 mg per day of glycosamionoglycans significantly lowered urinary oxalate levels in stone formers.3 Chondroitin sulfate is a type of glycosaminoglycan. A decrease in urinary oxalate levels should reduce the risk of stone formation.
Pumpkin Seeds
Two trials from Thailand reported that eating pumpkin seeds reduces urinary risk factors for forming kidney stones.Dose:
Refer to label instructionsPumpkin SeedsTwo trials from Thailand reported that eating pumpkin seeds reduces urinary risk factors for forming kidney stones.4,5 One of those trials, which studied the effects of pumpkin seeds on indicators of the risk of stone formation in children, used 60 mg per 2.2 pounds of body weight—the equivalent of only a fraction of an ounce per day for an adult.4 The active constituents of pumpkin seeds responsible for this action have not been identified.
Vitamin B6
Taking vitamin B6 with magnesium can inhibit oxalate stone formation.Dose:
Refer to label instructionsVitamin B6Both magnesium and vitamin B6 are used by the body to convert oxalate into other substances. Vitamin B6 deficiency leads to an increase in kidney stones as a result of elevated urinary oxalate.6 Vitamin B6 is also known to reduce elevated urinary oxalate in some stone formers who are not necessarily B6 deficient.7,8
Years ago, the Merck Manual recommended 100–200 mg of vitamin B6 and 200 mg of magnesium per day for some kidney stone formers with elevated urinary oxalate.9 Most trials have shown that supplementing with magnesium10,11,12 and/or vitamin B610,14 significantly lowers the risk of forming kidney stones. Results have varied from only a slight reduction in recurrences15 to a greater than 90% decrease in recurrences.11
Optimal supplemental levels of vitamin B6 and magnesium for people with kidney stones remain unknown. Some doctors advise 200–400 mg per day of magnesium. While the effective intake of vitamin B6 appears to be as low as 10–50 mg per day, certain people with elevated urinary oxalate may require much higher amounts, and therefore require medical supervision. In some cases, as much as 1,000 mg of vitamin B6 per day (a potentially toxic level) has been used successfully.17
Doctors who do advocate use of magnesium for people with a history of stone formation generally suggest the use of magnesium citrate because citrate itself reduces kidney stone recurrences. As with calcium supplementation, it appears important to take magnesium with meals in order for it to reduce kidney stone risks by lowering urinary oxalate.18
Vitamin E
In one study, supplementing with synthetic vitamin E was found to reduce several risk factors for kidney stone formation in people with elevated levels of urinary oxalate.Dose:
Refer to label instructionsVitamin EIn a double-blind trial, supplementation with 200 IU of synthetic vitamin E per day was found to reduce several risk factors for kidney stone formation in people with elevated levels of urinary oxalate.17