Another calcium question

[pkbites]

You may have seen Robert Barefoot hawking his “Coral Calcium” on an infomercial. (We’ve talked about him on the SDMB several times too). While I’m sure he is at least 49% huckster, my research shows that he is correct in his insistance of how important calcium is for our bodies. I have been taking 500mg of calcium 3 times a day, with vitamin D for years, so my intrest in calcium is not a new occurrance.

My question has to do with a statement he makes regarding the
absorption of calcium. He claims that taking 1000mg (the USRDA) of any calcium (except his coral calcium, of course:rolleyes: ) the body will only absorb about 2-5% of it.
Now wait a minute. My info tells me that taking vitamin D with calcium greatly enhances the absorption of calcium.
The problem is, he never specifies why, say, calcium carbronate, only absorbs 5%. Is there any proof to this. Am I wasting my money on the calcium I’ve been taking?

[Duck_Duck_Goose]

1. You are aware that coral calcium is just calcium carbonate, identical stuff to oyster shell calcium, etc.? Okay. I knew that you knew that.

2. Found this.

TUMS Home

Those studies that measure actual systemic calcium absorption show that calcium from most sources is well absorbed in healthy individuals. They also show that little acidity is necessary for calcium absorption, and that no basal gastric acidity seems to be necessary if calcium is taken with meals.7

Another study in the New England Journal of Medicine found no difference in the amount of calcium absorbed from equivalent amounts of various sources, including milk and several calcium salts, in fasting, healthy, young volunteers.8 This was true regardless of the solubility of the various forms of calcium.

The study concluded that, “The observation of similar calcium absorption from various calcium salts and milk in healthy young subjects suggests that there is little reason to choose one source of calcium over another on the basis of the efficiency of calcium absorption. Other variables such as cost, the number of tablets to be ingested, and intolerance to milk products are more pertinent in the choice of a source of supplemental calcium.”

The choice of supplement should be based on cost, ease of use and convenience, tolerability, and elemental calcium content. Calcium carbonate scores well on each of these counts.

So it doesn’t matter what kind of calcium you take, it’s all absorbed at about the same rate.

TUMS Home

Although nutrients such as iron, sodium, oxalate and magnesium may influence calcium’s effectiveness, vitamin D is the most important additional nutrient shown to enhance calcium’s ability to build and maintain bones

< snip >

Many studies on calcium’s effects in building and protecting bone and preventing fractures have shown a benefit from ensuring adequate vitamin D. Vitamin D stimulates intestinal calcium absorption and enhances the bone building process itself. One recent study showed that additional vitamin D increased the short term absorption of calcium even in healthy individuals with no apparent vitamin D deficiency.

Glaxo Smith Kline is a pharmaceutical company that presumably manufactures calcium supplements, but I see no reason to quibble with these quotes or their cites, as they back up what I’ve read on calcium, same as you.

[pkbites]

Wow, thanks for all the info Duck Duck Goose.