most people are calcium deficient(and deficient in many other minerals as well, especially sodium, potassium)... the idiotic recs by some famous authors and ''scientists'' of not consuming milk ''because only infants drink milk'' made people world wide calcium deficient...
calcium got over 10.000 functions in the body (vs. 3000 for magnesium).. i read the two books recommended on this page about calcium plus an extra one written by university professors/scientists(
https://www.amazon.com/Calcium-Hunger-Behavioral-Biological-Regulation/dp/0521791707)...
and calcium is considered the MOST important mineral for the body and many of us are not consuming it DAILY, and many of us exercise A LOT(like we all are olympic athletes) because it is heavily promoted by the fitness industry; we become more calcium deficient and the body will pull calcium out from the bones(but blood tests will show normal calcium levels and also sodium, while in reality you are severely deficient in both)...
just like with sodium/salt will show ''normal'' on blood test when in reality you are severely deficient.. with exercise and/or heat, sodium, chloride and calcium are lost the most.. those metabolic acids created by exercise and junk food must be neutralised by calcium... just look around how many people have osteoporosis and bone problems... lack of salt/sodium and calcium...
scientists in the past were aware of the difference between raw and pasteurised/heated milk(in regards to nutrient/mineral absorption)... but they still recommended pasteurised milk if one could not get raw, to get in the body some very needed calcium...they recommended at least 500ml per day
people over 50 and pregnant/lactating women need at least 1200mg/day... people in general need 1000mg/day (much more if you exercise)...
raw milk and raw cheese and powdered eggshells and coral marine calcium(with a natural 2:1 ratio of Ca-Mg) are the best sources according to my research...
the bulgarians, where most centarians live FUNCTIONALLY , mostly eat whole grains(source of copper and manganese) and drink loads of raw sour milk(source of probiotics, good fats, protein, calcium, potassium, phosphorus, and most nutrients) and eat vegetables(source of potassium), salt(source of sodium and chloride and other trace elements)