Calcium for vegans

[mccoy]

After re-reading MR's section on calcium in his supplementation for veg(etari)ans, I started to edit, in cronometer, Ca out of spinach and oxalate-rich vegetables. Also, I realized that calcium in tofu may not be there if the coagulant used is not Ca-based.

 

So, my cronometer levels of Ca plummeted down. No kale here in Italy, only some is available and dried. And no fortified foods.

What to do beyond pure supplementation?

 

I was pondering, when the very obvious answer materialized in my mind. Very much obvious, but lost in the background mental noise.

 

Water was the answer. I googled the calcium content in commercial mineral waters (those available in supermarkets), and there it is, a list with the top entries. The highest one, of a volcanic origin, contains 390 mg per liter. And that of course is very much available, being in its ionic form.

 

Yesterday I went to the supermarket and made of stock of that water. Since I never drink less than 1.5 liters per day, that's already almost 600 mg of available Ca, about 60% of the RDA. In the summer I very often drink 2 liters and more, which will allow me to be consistently above the RDA, together with the other vegan food.

 

Hope I won't have now to start worrying about too much calcium...

[TomBAvoider]

Anecdotally, epi research consistently shows that people in areas where they consume mineral rich waters have better health status - no doubt calcium might be part of that. I know that back in the day, on the list there were threads about what water to use for daily consumption, including in things like tea and coffee. My personal consumption of liquids (i.e. those I drink, not just in food) is almost exclusively tea, coffee and wine (occasional beer) - I rarely drink water by itself, but when I do, I try to drink good quality mineral water. If you use good quality water in everything you prepare (including things like soups), you should have decent mineral intake. You should probably take into account the other minerals in the water you consume, not just calcium. Also be careful for stuff in the water that is not healthy, such as arsenic. Make sure you have a good and reliable profile of the water you consume. 

[mccoy]

...You should probably take into account the other minerals in the water you consume, not just calcium. Also be careful for stuff in the water that is not healthy, such as arsenic. Make sure you have a good and reliable profile of the water you consume. 

 

Done, I've entered all the minerals listed, why not to enter precious Mg in cronometer? Although the only electrolite listed which can really have a significant influence on the RDA is calcium. But again, as you say, there are trace elements, metals and so on which probably have not even been analyzed and may contribute significantly to our needs. Of course, there may be something deleterious, hopefully the checks by the authorities will be able to point out eventual contaminants.

[mccoy]

I just realized that on the labels of some tofu products (the one I recently bought) they specify the coagulant used, in my case Calcium sulphate and Magnesium chloride. This allows to factor the Ca in to cronometer.

 

Today, with mineral water + tofu,  I almost reached 200% RDA

[mccoy]

Today my eye at the supermarket casually came across the label of the favourite mineral water of my wife: Calcium 610 mg/lt !!!! Also, Mg 90 mg/lt.

I instantaneously bought 24 liters. My wife won't have to complain that I'm stealing her water.

Now I have the opposite problem: maybe too much calcium in my daily intake. Hypermineralized mineral waters, that's undoubtedly the best Ca ++ source for vegans.

[Sibiriak]

I was recently looking into the evidence on possible harms of too much calcium intake (dietary and/or supplemental).  The data is confusing because there are so many differently designed studies,  many possible confounding factors,  and signficant issues related to concomitant magnesium,  vitamin D,  and vitamin K2 intake. 

Here's a simplified slide presentation overview of some of the recent evidence.   The author's  final conclusion is:  "Aim to reach, but not exceed, recommended intakes."

Calcium Supplementation:  Good for the Bone, Bad for the Heart?

https://medicine.yale.edu/lab/insogna/Andrea Singer Calcium Presentation at Yale Jan 13 2017_290285_284_5_v1.pdf

Calcium supplements: Good for the bone, bad for the heart? A systematic updated appraisal (2020)

Marco B. Morelli, Gaetano Santulli,^* and Jessica Gambardella

 

Quote

Large observational studies have shown that augmented concentrations of serum calcium can increase the risk of myocardial infarction (MI), therefore it seemed logical to consider potentially dangerous to rise peaks of circulating calcium since this process can advance dangerous (ectopic) calcifications. Reid and collaborators reported that ionized calcium concentration increased from a mean of 1.22–1.30 mmol/L following supplementation with 1 g of calcium, either as citrate or as lactate gluconate [13].

Therefore, it is plausible that augmented plasma levels of calcium might alter the systemic balance in favor of calcification [13], which becomes a serious health risk when it occurs as ectopic calcification.

The controversy on the actual role of calcium supplementation on cardiovascular risk has not been solved by meta-analyses (Table 2) of published studies, which have generated inconsistent results [14–21], showing how this important topic is debated and exposing the current uncertainty about optimal doses and regimens for supplementation and their overall effectiveness.

 

 

 

[Saul]

Yes -- But recommended intakes is higher than I would expect -- over 1 gram per day.   I supplement 1 gm a day as calcium hydroxyappetite -- the form that is probably best for bone growth.  (My supplement is basically ground up cow bones).  I also supplement Vitamin D.  I have a slight heart murmer -- two cardiologists that I've seen over the years say that it is benign.

My lipid levels is probably among the the best in the CR Society -- although I'm 79 yo.

I work out for 1 hour daily at the maximal resistance of the latest Precor Elliptical Cross Trainer with arm motion in my gym -- my feet moving a distance of ca. 5mi during the workout.

All of the above is probably good for osteoporosis, which I do have.

  --  Saul

[mccoy]

Thanks for the link Sibiriak, the takehome lesson I believe is that there is not much association between CVD and Calcium intake and only by the precautionary principle they suggest not to exceed the Adequate intake of 1000 mg/d. The review also hints at the difference between dietary and supplemental intake. Intake of Ca++ (the electrolite dissolved in water) for example is maybe different from intake in the form of inorganic  calcium found in supplements or bound calcium in food sources.

Another aspect is the positive correlation between Ca and prostate cancer which has been underlined in some studies. 

Another aspect yet: wheter  we should aim not to exceed the adequate intake of 1000 mg per day or not to exceed the tolerable upper level, 2000 or 2500 mg per day.

What I'm observing is that, by the use of hypermineralized waters, my calcium intake hovers around the upper level of 2250 mg.

My action is that I've set the cronometer upper level at 2500, since there is probably some ca in foods which gets bound to oxalates, even though I zeroed the Ca value of some oxalate-rich vegetable. And of course I discontinued any supplementation.

If I'm going to see persistently the red in the cronometer Ca bar, then I'm definitly going to use  less mineralized waters together with the more mineralized ones.

 

[mccoy]

Saul, as far as I remember, the reccomended intake is pretty high for the reasons discussed by Michael Rae in the thread on supplements for vegetarians, that is, there is conspicuous uncertainty, and a  large uncertainty, by statistical laws, means a higher estimate of the cautious value. The real average maybe far lower than that and the tolerable upper level might thus reveal too high. It's a gamble, as in other dietary aspects. 

If you have osteoporosis, the gamble shifts towards an higher Ca intake, of course. In my case, I find the gamble of an high Ca intake tolerable, since I did not suffer of kidney stones so far or gallbladder stones.

My gamble  is also based upon the fact that in my vegan transition I did not take high amounts of calcium, rather I've probably been below the adequate intake for a while (allowing for the copious oxalates I ate). So, by the present abundance of calcium, I might be shifting the balance to more favourable levels, even considering my present engagement in resistance training.

This in the presence of adequate vitamin D3 and K2, retinol and tocopherol.

Every situation appears to be subjective.

[Saul]

Be cautious about retinol -- it's poisonous.  One DOES need a small amount; but that is almost always satisfied for anyone who eats lots of fruits and vegetables -- which is all of us.

Carrotenoids are present in romaine lettuce, bell peppers, carrots and many other fruits and vegetables that we eat.  These are desirable; and your body is easily able to convert a portion of the carrotenoids that you have consumed into the retinol that is required.  Your body is much better to determine just how much to convert, than any computation that you might make, using cronometer or any other software.

But you can be certain that you do not need to -- and should not -- supplement retinol.

  --  Saul

 

 

[mccoy]

Saul, thanks for the reminder, I agree that the body, if no unfavourable polymorphisms exist, know very well how many carotenoids to convert into retinol. I reason in terms of retinol equivalents since in the past I've been deceived by apparently abundant amounts of carotenoids which corresponded though to low amounts of Retinol equivalent. I also agree that cronometer is not a precise tool,l that's all we have now though.

I don't use supplements of the liposoluble vitamins (except D3 in the wintertime), whereas I  do supplement the hydrosoluble vitamins of the B complex. 

[rjb112]

mccoy:  Regarding calcium for vegans, you may find this to be a little helpful.  It's a talk for vegans on "Where do you get your calcium and vitamin B12".  Do keep in mind that the intended audience probably has a lot less knowledge and experience than you do, so the material is presented at a beginner's level.  But you may find something of interest there.  It's on You Tube.  I pasted the URL, but I see the website has changed it and shows the entire "photo".  They do go into oxalic acid in spinach, parsley, swiss chard, and beet greens, and how those are not good calcium sources as a result of the oxalic acid.  Then they present some food sources of calcium for vegans.  Probably you could ignore the rest.....Also, just so you are forewarned, they are advertising for a course they have on nutrition for raw vegans, so they spend quite a bit of time discussing their product.  

 

[rjb112]

mccoy:  You might also find this helpful:  https://www.vrg.org/nutrition/calcium.php

Calcium in the Vegan Diet

by Reed Mangels, PhD, RD
I would combine that info with the info from below:

https://www.ars.usda.gov/northeast-area/beltsville-md-bhnrc/beltsville-human-nutrition-research-center/nutrient-data-laboratory/docs/oxalic-acid-content-of-selected-vegetables/

Oxalic Acid Content of Selected Vegetables

Then it could become more complicated if other factors were added in, such as phytates.

Hope this helps a little.

[Sibiriak]

Pitfalls in interpreting interventional studies for osteoporosis

Mohammad Shafi Kuchay, Beena Bansal, and Ambrish Mithal

Clin Cases Miner Bone Metab. 2017 Sep-Dec; 14(3): 329–331.

PMCID: PMC5762224 PMID: 29354162

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5762224/

 

Quote

Many professional organisations have made recommendations for optimal calcium intakes based predominantly on the results of calcium balance studies (3), including the recommendations from the Institute of Medicine in 2010 (4). Heaney et al. in 1977 evaluated calcium balance in 130 women aged 35 to 50 years (5, 6). They demonstrated that daily calcium intake associated with zero balance was about 1500 mg in untreated postmenopausal women. Thereafter 1500 mg of calcium became a generalised recommendation to all postmenopausal women.

Hunt and Johnson in 2007 examined data from a series of balance studies, which together included 73 women aged 20–75 years and 82 men aged 19–64 years (7). The daily calcium intake predicted to produce a neutral calcium balance was 741 mg, regardless of age or sex. This was about half the amount of calcium required for zero balance as demonstrated by Heaney et al., reflecting some inherent problems with calcium balance studies.

Hunt and Johnson concluded that calcium balance was highly resistant to a change in calcium intake across a broad range of typical dietary calcium intakes (415–1740 mg per day; between the ~25^th and >99^th percentiles of typical calcium intake for all female children and adults aged ≥9 year). Hence, homeostatic mechanisms for calcium metabolism are functional across a broad range of typical dietary calcium intakes to minimise calcium losses and accumulations.

 

Quote

After adulthood, changes in the skeleton are slow and takes years for accruing or losing any appreciable amount of bone mass. Proper interpretation of studies that evaluate the effect of nutrients (like calcium, vitamin D) and anti-resorptive agents (like bisphosphonates) on bone mass is important so that the true effect of the agent is measured correctly. In this report, we are highlighting two issues of utmost importance for correctly interpreting interventional studies for osteoporosis. One issue is the bone remodelling transient (BRT). It refers to a transient change in bone mineral density (BMD) by any agent that reduces remodeling space temporarily. This change is, however, not sustained for a long period and can be misinterpreted as a true gain in bone mass. The second issue is difference between calcium balance and bone balance.

Calcium balance is the difference between the amount of calcium ingested in a day and the amount of calcium lost in that day. Recommendations for dietary calcium intake are based on calcium balance studies that presume calcium balance as an equivalent for bone balance. However, these are two different entities and need to be distinguished. Dietary calcium requirements should be established by bone balance studies using bone densitometry, not by calcium balance studies.

[Sibiriak]

How much calcium do you really need? (Aug. 2017)

https://www.health.harvard.edu/staying-healthy/how-much-calcium-do-you-really-need

Quote

Dr. Walter Willett, chair of the Department of Nutrition at Harvard T.H. Chan School of Public Health, thinks you're likely to do just as well on half as much calcium  [as recommended].

"Essentially, I think that adults do not need 1,200 mg of calcium a day. The World Health Organization's recommendation of 500 mg is probably about right. The United Kingdom sets the goal at 700 mg, which is fine, too. It allows for a little leeway," he says.

Why the 1,200-mg recommendation?

Adequate calcium is necessary for good health, and not just because it's a major component of our bones. It also plays a vital role in keeping our organs and skeletal muscles working properly. The body gets the calcium it needs for basic functions by releasing the calcium stored in our bones into the blood through bone remodeling—the process by which bone is constantly broken down and rebuilt.

Because bone density drops when bone breakdown outpaces bone formation, scientists reasoned that maintaining an adequate level of calcium in the blood could keep the body from drawing it out of the bones. In the late 1970s, a couple of brief studies indicated that consuming 1,200 mg of calcium a day could preserve a postmenopausal woman's calcium balance.

Based on those studies, in 1997 an Institute of Medicine panel raised the recommendation for calcium intake from 800 mg to 1,200 mg a day for women over 50. That wasn't a sound decision, Dr. Willett says: "The recommendation was based on calcium balance studies that lasted just a few weeks. In fact, calcium balance is determined over the course of years." Moreover, there wasn't any evidence that consuming that much calcium actually prevented fractures. Nonetheless, the recommendation has been carried forward since then.

 

[mccoy]

rjb, thanks for the links!

Sibiriak, how much calcium have you decided to target presently?

[Sibiriak]

At this point,  I'm aiming for around 800mg,  but I'm reviewing the issue right now.  Unfortunately,  I don't think any scientific conclusions can be reached about optimum calcium intake--the evidence is too conflicting and problematic.   Here's another overall review:

The Calcium and Vitamin D Controversy

Bo Abrahamsen 

Ther Adv Musculoskelet Dis. 2017 May; 9(5): 107–114.

PMCID: PMC5394528 PMID: 28458722

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5394528/

It covers the evidence on calcium/vitamin d supplementation in relation to bone mineral density, fractures, cardiovascular concerns, mortality, and renal stones.The author's main conclusion is:

Quote

Though large clinical RCTs currently evaluate the effects of higher vitamin D doses (equivalent to 50–83 µg/d) there is no current research effort regarding the calcium controversy. In the absence of such studies it is not possible to provide clinicians with evidence-based recommendations regarding the best use of CaD [calcium + vitamin D]  supplementation.

Obviously,  that's not particularly helpful from an practical standpoint.  And there is unlikely to be any decisive new evidence forthcoming any time soon.

Quote

...the bulk of ongoing research focuses on higher dose vitamin D and not on calcium supplements. More than 700 trials of vitamin D that are currently recruiting or planning to recruit patients are registered at clinicaltrials.gov at the time of writing with an additional 240 ongoing trials registered with the European trials register. The largest ongoing trials are summarized in Table 3. By contrast, a search of these trials registers found no planned or ongoing vitamin D trials with calcium outside the specific areas of hyperparathyroidism, colon cancer prevention and prevention of renal stones in conditions linked to citrate deficiency. Hence, despite the combination of CaD having shown the strongest anti-fracture and survival benefits but also the strongest suspicion of renal and cardiovascular potential for harm, there is currently a complete lack of clinical trial activity to resolve this central controversy and inform clinical guidance to patients and public health strategies.

 

As you said above,  "every situation appears to be subjective."    My personal approach in this case is to step back a bit from the morass of studies and meta-analyses (but not ignore them) and put primary  focus  on an overall  longevity-diet approach such as Valter Longo's.  (Blue Zone diet calcium intake would be interesting to look into, btw).     I have been drinking a very modest amount of kefir which nevertheless provides a significant amount of bioavailable calcium, so  my need to look into supplementation has been less pressing than if I were a pure vegan. (I've gone back and forth about  eliminating the kefir, but haven't done so yet. It seems to provide a number of health benefits, but there are issues  with milk proteins etc.)   I do supplement vitamin D (and, importantly, vitamin K2),  given my location and lack of extended sunbathing.  I aim to keep 25(OH)D  levels around  40 ng/ml. 

 

[Sibiriak]

Quote

Mccoy: The review also hints at the difference between dietary and supplemental intake

Michael Rae wrote in his supplementation thread:  "Because calcium is required at relatively high doses, and inhibits the absorption of iron, zinc, and other minerals (but not magnesium, despite what you’ve heard^lxx), it’s best to spread your dose throughout the day (again, your ‘dose’ embracing both food and supplements); this also maximizes absorption."

But there may be an additional reason to spread out one's calcium "dose".   Mark Bolland, one of the leading researchers in the anti-supplementation camp,  writes:

Quote

The cause of the increased cardiovascular risk from calcium supplements remains unclear, but potential mechanisms have been extensively reviewed [Reid et al. 2010]. The finding of increased cardiovascular risk from calcium supplements but not dietary calcium intake in most observational studies [Al-Delaimy et al. 2003; Ascherio et al. 1998; Bostick et al. 1999; Iso et al. 1999; Knox, 1973; Li et al. 2012; Van der Vijver et al. 1992; Van Hemelrijck et al. 2013; Xiao et al. 2013] but not all studies [Michaelsson et al. 2013] has led to the hypothesis that the rapid and sustained increases in serum calcium after ingestion of a calcium supplement may have a central role.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4125316/

In order to avoid a rapid and sustained increase in serum calcium it would make sense to spread one's calcium supplement dose ( or sip mineral water) throughout the day.  This is purely speculative, of course.

A more detailed--and rather skeptical--discussion of this  issue can be found in the following review, under the "Mechanistic Considerations"  subheading:

The role of calcium supplementation in healthy musculoskeletal ageing [ETC.] 

Osteoporos Int. 2017 Feb; 28(2): 447–462.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5274536/