Question:
Can soy products inhibit calcium absorption?

I have been told recently that a nutritional speaker has stated that soy can somehow block or inhibit calcium absorption. As I use a lot of soy in my postop diet, I am of course concerned about whether this is true. Does anybody have any info about this?    — kimlasavio (posted on January 8, 2004)

January 8, 2004
hiya~ i don't think it's the soy per se but the protein of the soy that would block calcium absorption. your intestinal tract only has so many receptor sites to absorb nutrients and it will absorb protein before calcium so if you drink your protein shake 5 minutes after taking your calcium you most likely will not absorb the majority of the calcium. this is true with any kind of protein. i just space mine an hour apart and my levels are fine. (also make sure to space your iron & calcium intake apart - those two will bind and you won't absorb either). hope that helps, kate
   — jkb

January 8, 2004
J, I have never heard that protein, soy or whey, inhibits absorbtion of calcium before. Iron & calcium should not be taken together, that's well documented, but can you please point me towards any studies or info suggesting that protein inhibits absorbtion of calcium? Thanks.
   — Leslie F.