okay so how would absorbign calcium effect the bodies ability to absorb any other nutrient/mineral/vitamin..? i guess every other vitamin nutrient and mineral inside of milk and green leafy vegetables is useless since those items contain calcium? whats the deal here?
they compete for transport. similar to ingesting multiple aminos at one time. for instance tyrosine causes increases in dopamine and norepinephrine via tyrosine hydroxylase and ingesting 2 grams of tyrosine would leave one feeling speedy, but if you take it with other aminos, co transporters, symporters, antiporters etc cause multiple effects which cause tyrosines effects to be moot.
in the same way calcium decreases magnesium absorption, b6 increases zincs. there are multiple nutrient interactions. B12 is a cofactor in alot of reactions for example, so a lack would lead to other nutrient deficiets along. There are alot of examples. Milk is bad to take with green tea for example.