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Calcium supplements - read the label carefully!
Deborah T Gold, PhD posted:
If you take a calcium supplement, read the package label carefully. It will tell you the amount of elemental calcium or how much calcium the supplement provides. It will also tell you how many doses or pills you must take to get that amount. In some cases you need to take multiple pills to get the amount of calcium listed on the front of the bottle.
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Louise_WebMD_Staff responded:
I have heard mixed things about whether you should split the calcium up through out the day or if you can take it all at once. Is there a difference?
bonebabe replied to Louise_WebMD_Staff's response:
Yeah, there's a huge difference. Calcium is very hard to absorb into the gut. Because of this, no matter how much you might put in your stomach, you're only going to absorb about 500-600 mg at a time. The rest will be excreted in the urine. I get so annoyed at those commercials, while factually correct, say that such and such cereal gives you 100% of your daily calcium need. Yeah, it does, but you can't benefit from it.

Calcium supplements are absorbed best with food. We advise our patients to take one supplement with lunch and the other with eilther supper or a light snack at bedtime. Usually people get their most dietary calcium at breakfast.

It's also important to get 1000 IU of Vit D each day. Most calcium supplements have this added. Vit D is what sends calcium to the bones. Without it, your calcium intake will be mostly ineffective.

Read the labels carefully. Calcium carbonate is usually one pill in a 600 mg dose. Calcium citrate is usually two pills in one dose. So look at the label to see what you're getting.
TediH replied to bonebabe's response:
I have osteoarthritis and had a parathyroidectomy in 2006. I take 2,225 mg liquid calcium citrate with 900 mg magnesium and 4600 IU of Vit D. I was told that the absorbsion rate was much higer (90%-95%) by taking liquid and that calcium citrate was much better than calcium carbonate. So, am I not absorbing what I need?
bonebabe replied to TediH's response:
A liquid will be absorbed more quickly than a pill because it's already dissolved. Calcium citrate is not as dense as calcium carbonate (that's why 2 pills = one dose) and is often more easily absorbed. However, one type calcium is not better than another. Calcium is a mineral and calcium is calcium, no matter the type. The key is absorption. If you have a problem with digestion or gas, a citrate form might be better for you. No matter what type you take, though, your body just won't process more than 500-600 mg at a time.
An_223930 replied to bonebabe's response:
With all the confusing info out there on Calcium, can you please tell me if Marine Grade Coral Calcium is a better choice?? I am concerned about the cost and the huge list of trace minerals that are listed on these products, since I have no idea if they are safe. The ads for these products state that because they are made from pure or whole food sources, (as do many other supplements) that they are a much better source of Calcium??

I have also been hearing that Vitamin D intake should be 5000 IU, where you have stated 1000 IU?? They also suggest a 2 to 1 ratio of Calcium and Magnesium, is this correct??

I have tried taking Calcium supplements with food and splitting the pills into 2 doses, but find I still feel a little nausea, though minor, I have heard the Coral Calcium does not cause this side effect.

I take 75 mcg of Synthroid a day and have heard that this drug causes Calcium loss and am not sure what dosage of Calcium I should be taking?? I am 61, post menapausal with a diet that needs improvement (working on that) and planning to get back to a daily exercise routine immediately.

bonebabe replied to An_223930's response:
Save your money. The coral calcium has pretty much been revealed to be a marketing scam. Calcium is a mineral. There is no good or bad calcium. It can't be broken down; therefore, you can take it in any form or price range. We do caution our patients about oyster shell calcium as there may be a problem with lead content.

If you can't get your 1200 mg of calcium in food sources, find a calcium supplement that doesn't cause you nausea or constipation. It can be as simple as tums or a supplement with added "enhancers."

The National Osteoporosis Foundation currently recommends 1200 mg of calcium each day (body can only absorb 500-600 mg at a time) and 800-1000 IU of Vit D.

Log on to the National Osteoporosis Foundation website ( ) for more information which may answer any other questions you might have.
Michael Lewiecki, MD, FACP, FACE replied to An_223930's response:
The NOF does not recommend specific brands or products. You should try to get at least 1,200 mg of calcium daily in diet plus supplements, if needed. The most common type of calcium supplement is calcium carbonate, which should be taken with meals to assure good absorption. Another type of calcium supplement is calcium citrate, which can be taken with or without food. It is best to take no more than 600 mg of calcium at one time. Getting more calcium than you need is not beneficial and may be harmful. For more information, including tips for finding a product that is safe, please visit . You can test a calcium supplement for absorption, by placing it in vinegar for 30 minutes. If it doesn't dissolve in about that time, it may not dissolve well in your stomach.

The NOF recommends 800-1,000 international units of vitamin D every day for people age 50 and older. Some people need more. You can find out if you are getting enough vitamin D by having a blood test for 25-hydroxyvitamin D. This is discussed in more detail at (scroll down to "Lab Test to Check Your Vitamin D Level").

Regarding magnesium, most of us get an adequate amount in our diets. Dietary sources of magnesium that are especially good include beans, nuts, seeds, legumes and a variety of vegetables such as spinach, artichoke and okra. People who eat a healthy diet get an adequate amount of magnesium for their bones. If there are malabsorption problems, your healthcare provider should be able to provide guidelines for taking a magnesium supplement. Extra magnesium may also be helpful when calcium supplements cause constipation, since it has a mild laxative effect that may result in normal bowel function. There are products available that combine calcium and magnesium in a single pill that are useful when both need to be taken.
Signoret replied to An_223930's response:
More and more doctors are recommending 5,000 IU Vit. D3 daily. That's way below the level that could cause toxicity. I take 5,000 IU myself, with my doctor's blessing!
berns70 replied to bonebabe's response:

Is there any injections for calcium. Is this safe. They said it absorbs faster. They said the shot is every year. Depending on the result. Is there vit D injection as well?

bonebabe replied to berns70's response:
I'm not familiar with calcium injections. Because the body can't absorb much calcium at a time, I doubt it's given by injection. I think you're referring to the Reclast once yearly injection. Reclast is an osteo drug much like Fosamax or Actonel but is given by infusion.

Vitamin D booster doses are given by injection until you're at a point where you can maintain with the pills. Your doctor can advise you on this.
deloris47 replied to bonebabe's response:
Does liquid calicum work as good.
bonebabe replied to deloris47's response:
Liquid calcium is fine. It will most likely be absorbed more quickly than swallowing a pill. Just make sure you read the labels and are getting about 500-600 mg in a single dose. More than 600 mg won't be absorbed and less isn't enough. You'll need to do this twice a day, preferably with meals.

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