D supplementation linked to increased kidney stone and hypercalciuria risk; K2 for consideration
Recently there has been huge increase in vitamin D prescription in the general population due to the fact that low 25-hydroxyvitamin D serum levels have been associated with a broad spectrum of diseases. In prospective and epidemiological studies evaluating vitamin D alone or in association with calcium supplements researchers have observed an increased frequency of kidney stone episodes. It is a medical challenge now to identify the alleles predisposing some groups of patients to increased urinary calcium excretion in response to vitamin D supplements and high 25-hydroxyvitamin D serum levels.
The findings of a broad literature search of two French researchers on the relationship between vitamin D, hypercalciuria and kidney stones were published as a review in Nutrients. It seems likely that some predisposed individuals, possibly prone to transforming 25-hydroxyvitamin D into calcitriol, with a reduced capacity for degrading calcitriol, or those who are more “sensitive” to vitamin D signaling, are more at risk of developing hypercalciuria and kidney stones in response to vitamin D supplements. A question has been raised concerning the potential role of vitamin D prescribed during infancy, since Randall’s plaques that precede the development of kidney stones are more frequently observed in children nowadays, which may in turn lead to the formation of stones years or decades later.
Dr. Katarzyna Maresz, president of the International Science and Health Foundation, points out the fact that it has already been shown by Wei et al (2017) in a Mendelian randomization study previously conducted in a Flemish population that the risk of nephrolithiasis (kidney stones) increases with vitamin K shortage, as exemplified by higher plasma levels of desphospho-uncarboxylated MGP (dp-ucMGP). “The fact that Western population is vitamin K deficient is well known. More than one-third of the study participants had a dp-ucMGP level higher than optimal for the prevention of macrovascular complications. These findings suggest that increasing the dietary intake of vitamin K2 decreases the not only the risk of kidney stones, but also hypertension, diabetes mellitus or CKD, so it should be recommended to use K2 with D3 too,” she emphasizes.
References:
- Letavernier E and Daudon M (2018) Vitamin D, Hypercalciuria and Kidney Stones. Nutrients 10(3): 366. doi: 10.3390/nu10030366
- Wei et al. (2017) The risk of nephrolithiasis is causally related to inactive matrix Gla protein, a marker of vitamin K status: a Mendelian randomization study in a Flemish population. Nephrol Dial Transplant 1–9.