Calcium absorption blockers - Bone Health and O...

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Calcium absorption blockers

SpaghettiIsGood profile image

I was trying to add calcium to my diet, and came across a website that said certain foods block calcium absorption. When I saw that, I tried to find other websites that said the same thing, but I was hoping I wouldn't find that. Unfortunately, I did find quite a few websites that say spinach, beans and whole grains block calcium absorption. In other words, if you eat dairy or take calcium pills, and then eat rice and beans an hour later, you've eaten the dairy/calcium pills for nothing.

I can't find specifics on how much of a blocker a certain food is.

Is it true? Must we separate our calcium and our calcium blockers (like spinach etc) by 4 hours?

Also, after a certain age, calcium gets absorbed by the body a lot less. Try as we may, after a certain age, it will take years and years to see a small improvement in the bones. That's why they invented all those bone drugs that build bone density, but not not bone strength. Does anyone else have different info?

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HeronNS profile image
HeronNS

I can't imagine you would have to wait that long, although it is possible if you simply eat the offending food at a different meal. I also think there are things you can do to promote calcium absorption, and some types of calcium are better absorbed by us than others. Calcium citrate, for example, is better than calcium carbonate. And calcium in food is best, although as you know some foods simply don't release their calcium easily - I've heard for a long time that spinach is like that, but you can cook it, and that makes it less problematic. Some foods promote absorption, like yoghurt and citrus.

This may be a less depressing website for you to peruse:

spineuniverse.com/condition...

As for your other question which I think is not so much can I keep on getting enough calcium in my diet as how can I maintain my bone health. The answer is yes you can. Have a read of my story, and also if you have some specific concerns, have a read of the item which talks about secondary causes of osteoporosis:

healthunlocked.com/pmrgcauk...

osteoporosis.ca/medical-con...

Hi SpaghettilsGood,

Here at the ROS we have a fact sheet that explains just this. Here is a link. It also gives lots of information about minerals and vitamins and how they help bones.

strwebprdmedia.blob.core.wi...

SpaghettiIsGood profile image
SpaghettiIsGood in reply to

Indeed, pages 6 & 7 do talk about calcium blockers. Phytates is the word for that, which I saw in your fact sheet. It says: Phytates

and oxalates are found in a wide range of foods, but most contain only small amounts and so only bind to small amounts of calcium. Therefore they usually

have only a small effect on calcium absorption if

a calcium-rich diet is taken. Also, calcium taken at other times of the day is not affected.

That's good to know. I'm also looking for studies and links that provide specific numbers.

I like this question and answer from the fact sheet: Should I eliminate these foods from my diet?

No, because these foods contain valuable nutrients. Instead, limit their effects on calcium absorption by having a calcium-rich diet.

That's a good answer. To me, that means eating more calcium than I usually eat, and already it's hard enough just getting what I do get!

in reply to SpaghettiIsGood

The general advice is to have plenty in your diet. But as you are worried about how much, there is an Edinburgh university calculator that is the only authentic way of checking how much you get. If you fall short of the recommended 700mg each day, it is ok to make the difference up with a supplement.

Here is the link to that page. theros.org.uk/information-a...

If you scroll down to the "Do I need a calcium supplement" bit, the link to the calculator is in bold.

All of the information in this factsheet has been checked, so it is a reliable source of information.

I hope this helps SpaghettilsGood.

FearFracture profile image
FearFracture

Yes, some foods do “limit” calcium absorption but it’s not as simple as blocking all the calcium. I believe it has to do w/ the calcium binding w/ something else in the food. For the most part, if you are getting 1200-1500mg of calcium via diet and supplements daily you don’t have to over worry about this.

What I discovered in my research on calcium that seems like info doctors should bother to tell patients is that your body can’t absorb large quantities of calcium at one time. For instance, if you ate 2 slices of pizza 🍕 with cheese and drank two, 8 oz glasses of milk for dinner, approximately 1/2 of the calcium you thought you were getting, your body can’t possibly absorb. Taking more that 500 mg at 1 time is somewhat pointless. The larger the quantity of calcium taken the lower the % of uptake. After finding this out, on my own, I changed my calcium supplements from a 600mg pill to Citracal Petites ( each pill contains 200 mg of calcium). I aim for a total of 1200-1500 mg of calcium each day (that’s through diet and supplements) and I make sure I’m getting “doses” of calcium throughout the day, rather than large quantities all at once.

Last January, when I was researching how the body absorbs calcium, another thing that I read was that the body “repairs” bones/muscle at night while we sleep so I decided to start taking one calcium supplement right before I go to bed at night (I would prefer to drink a glass of milk but that would mean getting up to use the restroom a couple of times during the night). About 2-3 weeks ago, while doing research before my bone turnover marker blood tests, I found this article which seems to support my decision to make calcium the last thing I take before bed. It states, “The intake of food influences bone turnover. Dietary calcium appears to inhibit bone resorption. Calcium supplements taken in the evening significantly reduce resorption markers, in the fasting state the next morning.

nps.org.au/australian-presc...

Given that taking a calcium supplement right before bed is a simple thing to do, you’d think doctors might bother to mention this also.

SpaghettiIsGood profile image
SpaghettiIsGood in reply to FearFracture

That website is very good. I believe you're onto something about how calcium binds with something else rather than it being blocked.

One does have to wonder why doctor s don't inform their patients to only take 500 mg at a time of calcium. Shucks, my first rheum didn't even tell me to take/eat calcium (but did prescribe vitamin D3).

Now that you mention it, I do take 500 mg with my last med at night. I didn't even know I was doing a good thing for myself by taking it later in the evening.

Which reminds me...why is my rheum telling me to cut back on calcium to 650 mg a day (mg changed to less identify me)? And why doesn't my GP know that calcium supplements could cause calcification? I guess if they did more research after obtaining their license, they'd be more like us who are quite informed.

goatsmilk profile image
goatsmilk in reply to FearFracture

Thank you for all the help

DeannaAlphi profile image
DeannaAlphi

Hi there. Balance of minerals etc in our bodies is important. There has never been a clinical trial to say that calcium is any more important than for instance magnesium. Someone simply concluded that because calcium is in bones, taking more may help. I stopped taking calcium supplements because it was forming lumps under my skin and who knows where else in my body. Vitamin K is important to transport calcium to our bones. Vitamins and minerals all work together and we are still learning about how they do.

One thing which may help you is that Phosphoric acid which is abundant in fizzy drinks, robs our body of calcium from our teeth and bones to maintain the ratio of phosphorous to calcium needed by our body. It can be replaced as it is consumed in other foods but I believe taking calcium alone is not the answer. When I learned this, I identified that the fizzy drinks which I regularly and freely consumed were one of the major causes of my osteoporosis. I no longer drink fizzy drinks other than appletize which does not contain phosphoric acid.

There are foods which they say block short term absorption of calcium, however, these foods also contain other important nutrients which our bodies need. May I suggest that a varied diet, as free as possible from artificial preservatives and chemical additives is more positive than avoiding calcium blocking foods. Calcium is only one of many important nutrients for our bones. I made a list of all of the known important nutrients for our bones, then separate lists of the the foods which contain high amounts. At the top of each list , the recommended amount we need. By doing this I also identified that the green foods which I had never liked were important for bone health etc etc. Now I sneak these foods into soups and smoothies (still don't like them, never grew up).

We are all different. it would be interesting to compare, if we all researched causes of our own osteoporosis, again by making lists. I have great respect for and gratitude to many people on this site who have taken responsibility for their own wellbeing by doing their own research and sharing their experiences and knowledge.

Wish you the best with your journey. xx

FearFracture profile image
FearFracture in reply to DeannaAlphi

I drank a lot of caffiene free diet cola thinking that it was fine because it didn't have added sugar or caffiene. A few yrs ago, I went a step further and switched from caffiene free diet cola to diet ginger ale (ginger ale doesn't contain caffiene) and last November, after learning that the phosphorus in carbonated beverages could harm my bones, I gave up all sodas--over the last year I haven't had more than 12 oz of colas. I'm hoping this is just one more step in helping my bones potentially rebuild.

Have you seen an improvement in your BMD (t-scores) since giving up colas?

DeannaAlphi profile image
DeannaAlphi in reply to FearFracture

Hi. I made lots of bone positive changes to my diet and lifestyle. A few years ago I was crashed into another couple, doing a very fast rock n roll. Nastily broke my wrist, leading to loss of use of my fingers on that hand. The hospital nurse broke the news I had osteoporosis and wanted me to have a bone scan. When she realised I already knew because of former vertebral fractures and that I had refused medication....she withdrew the offer of a dexa scan. (I'm sensitive to many ingredients in medications so with my gp's approval I self medicate the best way i can. Even had 3 strains of covid with no medications of consultation with the nhs).

Fizzy drinks was only one of many things which contributed to my osteoporosis. Long term use of steroids and asthma medications was a main one. Ironically the asthma was caused by ingredients of other medication. Took about 3 years to sort it all out. I'm eternally grateful to our practice nurse who used basic common sense which the doctors and specialists didn't.

I managed to get another dexa scan when I asked the head nurse if the scan was for the benefit of the patient or the drug companies. I wanted to see if my efforts to help myself were making a difference.....and then if not, perhaps I would rethink and try some kind of medication. The same machine was used, they would not give me a printout of it the result. I got a copy in the end through another doctor.....it made no sense when I compared the result to the first one I had. I got an REM scan privately and the consultant said that both Dexa scan results did not make any sense.

I believe the Dexa scan is purely a guide which doctors use to prescribe medication. I'm 68 years old now and do not expect to improve my bone density. I hope to have slowed down the process and perhaps strengthened my bones somewhat. Strength and density are two different things, and I don't believe we have a reliable method of measuring either. So the answer to your question is I do not know. I can only hope. xx

FearFracture profile image
FearFracture in reply to DeannaAlphi

I have made lots of bone positive changes to my diet and lifestyle too. I hope your bones are improving and I hope mine are too :-) I had a my 3rd DEXA yesterday afternoon so I should have the results in a few days. The biggest contributor to my bone loss is probably early menopause--I was in my early 30s when it completely ended which means for 1/2 of my 20s I was perimenopausal and I didn't know it.

I was interested in having an REM scan but the machines aren't as available in the US. I called a facility that is in another state, that has an Echolight REM scanner but since it is out of state my health insurance won't cover any of the costs--I would have to pay aprpoximately $650 out of pocket plus the cost of the trip, so I decided to search for a facility in my state with DEXA with TBS capabilities--it took about 3 months to find and confirm and get an appt and when I walked into the room to have the scan done the technician looked at me and said, "We might not be able to give you a TBS score." LOL. That was last week.

Yesterday, I went back to my original imagining center and had a DEXA done so I will at least have numbers to compare to my previous DEXAs. I took the meds and I have made lifestyle changes and I would like to know if anything is working on not. If my DEXA shows a decline there is no reason to continue with the meds, and even if my bones have improved, I might skipped the meds and simply continue to try to improve my bones on my own.

DeannaAlphi profile image
DeannaAlphi in reply to FearFracture

Hi again. Similar to you but for different reasons,I took pills from my early 30's which totally stopped my periods. No mention of long term side effects when prescribed. Ironically the same pills, progesterone are recommended to help bones.....and they won't prescribe them. Let us know how your scan results compare. Xx

FearFracture profile image
FearFracture in reply to DeannaAlphi

For anyone who may stumble upon my post (so they have some context): I went through early menopause (early 30s) did not do HRT. Have never smoked, rarely drink, don't do drugs, have always considered myself to be a relatively healthy person. I'm petite, 4'11", currently weigh 107 lbs but for most of my adult life my weight ranged from 92 - 101 lbs. I was diagonised with osteoporosis in 2019 at age 50. I have no fragility fractures and haven't lost any height. Started taking alendronate in January 2020, 6 months after diagnosis. Stopped taking alendronate after 1.5 yrs (the week of my 2021 DEXA) due to digestive tract issues. Took a 4 month bisphosphonate holiday and in November of 2021 had my 1st zoledronic acid infusion. As of today, 12-13-22, have not had any major side effects from taking bisphosphonates.

GE Lunar DEXA results

July 2019 July 2021 December 2022

LUMBAR SPINE

L1 -4.5 -3.8 -4.1

L2 -4.3 -4.2 -4.2

L3 -3.7 -3.3 -3.5

L4 -3.4 -3.5 -2.9

Total L Spine -3.9 -3.7 -3.6

RIGHT HIP

Right Neck -2.7 -3.1 -2.9

Total Right Femur -3.0 -3.0 -2.8

LEFT HIP

Left Neck -3.3 -3.2 -3.1

Total Left Femur -3.4 -2.9 -3.0

==========================================================

My personal take is at least my numbers are improving if you compare my 2022 DEXA to my 2019 DEXA. My right neck seems to have decreased from 2019 to 2022 if you look at the numbers reported, but I think that there was something off with my 2019 DEXA--there was a noticeable difference in BMD between my left and right hips and from what others have shared, unless there is a reason (cancer, a hurt leg or hip, etc) generally left and right hip BMD are somewhat in alignment--I think that -2.7 for my right hip in 2019 is incorrect, that it was probably lower, and that my left hip numbers were too low and were actually higher than reported. The increase in my left hip from 2019 to 2021 on my DEXAs was over 9% and others have said that bisphosphonates don't "target" one area, they generally have an overall effect--no other areas showed that much improvement between 2019 and 2021.

I'm happy that I'm not continuing to lose more bone (for the moment) but I was really hoping for a bigger improvement, given that I had a zoledronic acid infusion and was not really thrilled about having it. Of course, if I continue to see .1 increases in my T-scores, in 11ish years, at approximately age 65, I will no longer have osteoporosis--I will fall in the osteopenia range--LOL.

I have an appt with my endocrinologist this week and I'm sure he's going to be thrilled with my gains and want me to have another infusion. I'm more inclined to skip the infusion and to try to work on improving my bones via weigh training and diet etc.

If you or anyone has an opinion or thoughts, please share.

SpaghettiIsGood profile image
SpaghettiIsGood

Yes, I read that consuming fizzy drinks produces less favorable health outcomes.

I have read what you said above on other websites (eat a varied healthy diet) and that should balance out the calcium vs. anti-calcium foods. I wouldn't want to eliminate those foods, either, because, like you said, they're valuable to our health.

I try to sneak spinach into everything hoping the other flavors will do it a favor.

Since others have written about calcium blockers, I'd like to see that research, but nooooo, that would be too easy! This info is not to be had!

FearFracture profile image
FearFracture in reply to SpaghettiIsGood

Spinach is a green high in calcium but it blocks absorption of calcium to a degree. I've recently added baby kale and baby arugala to my diet--I don't eat either every day but I try to get more of them in general.

SpaghettiIsGood profile image
SpaghettiIsGood

I think rheumatoid arthritis contributes to osteoporosis. Also, if a person didn't build up a store of calcium as they grew up, couldn't that contribute?

SpaghettiIsGood profile image
SpaghettiIsGood in reply to SpaghettiIsGood

I read that yes, it definitely can. Ps-i didn't drink many fizzies throughout life, but still ended up with osteoporosis. What is the abbreviation for osteoporosis?

FearFracture profile image
FearFracture

Here are my most recent DEXA results, well, the results that were on the radiologist's summary report.

Why the HELL do I have to fight with every freaking imaging center to get my, MY DEXA report and the ancillary data. I really don't give a flying fig what some radiologist thinks. How hard is it to learn the DEXA software and print out the report and hand it to the patient.

My most recent DEXA was done on 12-14-23 and I was just given a summary today when I went to see my endocrinologist.

I had to go to a different imaging center because the DEXA machine at the imaging center that I used in 2019, 2021, and 2022 broke and they are having to get a new machine. The good thing about this is that I was finally able to get away from that awful imaging center--I spent 3 months in 2021 "fighting" with them to get my DEXA report and ancillary data and this year their scheduling software wasn't working so they couldn't schedule my annual DEXA for over a month and then when I finally did get them to schedule it and I called to confirm a month later they told me it was going to be cancelled because their DEXA machine was broken--I had to call them to find this out...when were they going to tell me so I could make other arrangements.

So I started over with a new imaging center that uses a GE Lunar scanner.

When I went in to have my 2023 DEXA, I explained to the technician that I wanted my full DEXA report and the ancillary data and she insisted that is not how they do it, that they are special and a radiologist writes the report--does she really not know that is what all imaging centers do, or at least the three I have been to.

Of course, I never received any results from this new imaging center, but my endocrinologist had the radiologist's sloppy report. Why do I call it sloppy because at the top of the report it says "Mammography Report". Additionally, they scanned my left arm and there is no mention of the results for that part of the scan, which I was told would be included. She listed my left femoral neck as being "osteopenic"--my left femoral neck (per the report) has a T-score of -2.8 so is the t-score in the report wrong or is it supposed to say osteoporotic. Additionally, per this radiologist, "L3 vertebral body has been deleted from the study secondary to degenerative sclerotic changes which may falsely elevate bone mineral density" to which I reply BS. I had two, not one but two, bone density tests last year. One on a GE Lunar and the other on a Hologic (the Hologic DEXA included a TBS)--neither of those radiologists said there was "degenerative sclerotic changes" to my L3. I do not believe that between December of 2022 and December of 2023 that there has been a major negative change to my L3. Also on the Hologic DEXA that I had last year, the TBS (trabecular bone score) for my L3 was the highest of the four vertebrae scanned. Maybe I am wrong and this one radiologist saw something that wasn't found on my lumbar MRI, the multiple spine x-rays I've had, or any of my other 4 DEXA scans, but I'm certainly not going to take her word for it without being given my full report and the supporting ancillary data.

Note, on my way home from my endocrinologist appt this morning, I stopped by the imaging center and asked to speak to the manager and was told that she doesn't work on the premises (this imaging center is affiliated with a hospital) but I did get her name and number and I have already called and left her a message requesting my health records--MINE--which per HIPAA laws, they have to give to me! My message was polite and I realize that we are close to the holidays but if I don't get a reasonably timely response, I am already determined to write a letter and send it to her, and the first part of the letter will simply request my full DEXA report and ancillary data, and I will end that letter with a second letter stating that I have run into issues with getting my DEXA reports from other imaging facilities and in an effort to save myself time, this is my follow-up letter, and in the follow-up letter I will document everything and say how it is a HIPAA violation for them not to provide me with my information and that if I don't have my full DEXA and ancillary data w/i the next __ weeks that I will be forwarding a copy of the letter to the CEO of the Hospital and/or the media.

Now, on to what the radiologist claims my results were:

2023 DEXA / GE Lunar

Lumbar Spine (L1, L2 and L4) T-score -3.8

Left Hip, Total, -3.0

Left Femoral Neck, -2.8

Right Hip, Total, -2.6

Right Femoral Neck, -2.8

And as previously stated, the radiologist simply decided not to report any data regarding my left forearm DEXA scan???

If you look above an my previous post that shows my previous 3 GE Lunar DEXA scan T-scores, you will see that per this radiologist my total spine t-score has decreased, my left femoral neck improved nicely (2022 T-score was -3.1, 2023 T-score shows -2.8) but my total left hip remained unchanged (both 2022 and 2023 T-scores show -3.0), and my right femoral neck has slightly improved and my total right hip has slightly improved (2022 T-score was -2.8, 2023 T-score shows -2.6).

As my endocrinologist went over the results of the DEXA scan, when he mentioned the improvements, I said "WooHoo" and he sharply stated, "You can't compare this data with last year because it's on a different machine."

He is an ass.

I know that you can't compare the data, but the fact that my numbers even on a different machine aren't slipping into the -4.0 range is a win to me. I really don't put a lot of stock in the numbers in this radiologist's report but it's all I have to go on for now and most importantly, to date, I'm still fracture free.

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