Which Calcium Causes Constipation?

Research / May 17, 2013

It is very typical that most calcium supplements (that usually only have added vitamin D) often cause constipation – as well other gastrointestinal issues like bloating, gas, and cramps, or all of them!

There’s a good chance that you have first hand experience and is why you’re reading this.

It’s a big problem because it deters you from taking the necessary dosage of calcium day in and day out.

One of the main reasons supplements don’t work is simply lack of ‘compliance’ to the schedule of regularly taking them. Hurdles to supplement compliance are the size (and numbers) of the capsule or pill, cost and tolerability. Constipation, and bloating, gas, and cramps fall into the last category. If your body does not tolerate your vitamin pill, you will soon stop taking it.

So in effect, because it’s a barrier to regularly taking calcium, constipation is actually a cause of osteoporosis.

What’s Your (Calcium) Type?

The most common type of calcium and the one that causes the most gastrointestinal discomfort  is from rock. That’s right –  your supplement is most likely calcium derived from limestone or marble (described on your label as ‘calcium from calcium carbonate’).

Why do we eat rock calcium (and since the 1930s when it was first introduced)?

Because rocks are cheap, rich in calcium (40%) and capable of slowing bone loss.

See, we naturally lose about 1% of our bone per year after age 35. For decades, rocky calcium carbonate has cut that in half so we only lost about 0.5% per year. Given no other calcium (from shell, coral or cattle bone) could boast anything more, slowing bone loss with rock calcium was better than not slowing it at all.

But a very uncomfortable side effect of rock calcium carbonate that we’ve tried to accept is constipation, as well other gastrointestinal issues like bloating, gas, and cramps.

These gastro issues happen because rock calcium carbonate essentially turns off the production of stomach acids.

This is why rock is used as the main component in antacids like Tums. It works great if you suffer from acid reflux and heartburn – but your digestive system pays the price!

If stomach acids aren’t there to churn and break down your food, then it makes sense that constipation, bloating, gas, and cramps will result.

The Cause and the Cure

As odd as it seems, calcium can be both a cause and remedy for constipation: the wrong kind of calcium, and taken excessively (more than 1500 mg/day) can make matters worse.

Normally, calcium keeps your colon clean by combining with excess bile and decayed fat to form a benign insoluble soap, which is excreted with your stool. But too much leads to digestive problems, as well as other problems such as unwanted buildup of calcium in the arteries.

Magnesium Means Movement

If your calcium supplement (or your diet) lacks magnesium then trips to the washroom become even more rare. Magnesium is very important for good digestion because it is a natural, gentle laxative. When feeling stressed, anxious or worried, magnesium relaxes your colon walls. (1)

Magnesium reduces tension on the walls of your colon which allows for a normal peristaltic (“a radially symmetrical contraction and relaxation of muscles which propagates in a wave down the muscular tube”) (2) action. Also, magnesium attracts water which means more gets to your colon – only a good thing regarding your digestive tract because water makes your stools softer.

Regularly including magnesium rich foods in your diet is just good housekeeping and will keep you regular.

Here are The Top 10 Sources of Mighty Magnesium to commit to memory:

  • Bran – Rice, Wheat, and Oat
  • Dried Herbs – Dried coriander provides the most magnesium with 694mg (174% Daily Value) per 100 gram serving, or 14mg (3% DV) per tablespoon. It is followed by Chives (160% DV), Spearmint (151% DV), Dill (112% DV), Sage (107% DV), Basil (106% DV), and Savory (95% DV)
  • Squash, Pumpkin, and Watermelon Seeds (Dried or Roasted)
  • Cocoa Powder – Dark Chocolate (who says all the tasty things are unhealthy?)
  • Flax, Sesame Seeds, and Sesame Butter (Tahini)
  • Brazil Nuts
  • Sunflower Seeds
  • Almonds and Cashews – Mixed nuts, Pine Nuts
  • Molasses
  • Dry Roasted Soybeans (Edamame) (3)

Is Your Tank Full

But in our hectic times it’s hard to always eat well and keep calcium and magnesium mineral levels where they should be. And that’s where supplements re-enter the picture..

Why? Because our food is no longer farmed as it was for millennia – in soil that was mineral rich. Acreages are no longer left fallow for seasons to allow the minerals to replenish, as that would interrupt big business profits.

This is not guesswork either – many lab tests have proven that vitamin and mineral levels in many of the most common veggies (broccoli and tomatoes and spinach, for example) are 50% less than they were in the 1950s! And similar numbers show up in the other food groups like meat and dairy because, as you likely guessed, our livestock are also eating vitamin depleted foods.

This means that you have to eat double the amount that was consumed a couple generations ago to get the same amount of calcium and magnesium. Not very likely!

It’s best to eat all organic foods, and that will help you get proper amount of calcium and magnesium, as organic foods are more vitamin rich. If you’re one of the few who can afford to do this consistently and you never deviate, then you do not need vitamins.

However, if you’re like the majority you shop at the big supermarkets and buy what’s on special – not organic foods that are often priced 30% more. And do you eat on the fly; at restaurants; while traveling and get together etc? This is how dietary compromises are so easily made and why supplements are a convenient and cheap insurance.

But how to deal with all those uncomfortable side effects?

Relief Is Here

Well now organic marine algaes, called algas calcareas (in spanish), very rich in calcium (30%) have been discovered that do not lead to ANY constipation or bloating, gas, and cramps. The algae naturally contain other important trace minerals, including magnesium, which sets them far apart from single element rock calcium.

Because the calcium (and all the minerals) is from plant, the body naturally absorbs it much more readily than rock, which comes as no surprise.  The algaes are not simply calcium carbonate, but a mixture of calcium types.

So your stomach acid is not turned off when eating plant calcium, and can go about its job of breaking it down. By doing so, more of the calcium and other minerals is absorbed and gets to where it should go – your bones. And what’s not needed is easily passed through the digestive tract.

Four Fibrous Foods to Feast On

Consuming highly fibrous foods like algae, as well as intestinal friendly items will further encourage good digestion for you.

Try as much as possible to do your digestive system a favor by eating generous amounts of:

  • Legumes – split peas, lentils, black beans, almonds, pecans
  • Veggies – broccoli, peas, carrots, potatoes, brussel sprouts, corn
  • Fruit – bananas, strawberries, pears, oranges, apples, figs, raisins
  • Grains – buckwheat, whole grain cereals, barley, brown rice

Also, by drinking more water and regularly exercising you can further minimize any digestive issues you may have. (4)

And increasing fluid intake and your physical regimen has many fringe benefits besides gastrointestinal ones. Because weight bearing exercise is a key component of good bone health and is scientifically proven to help to keep your bones strong. It is equally as important as the calcium and minerals you take.

All Calcium is NOT Created Equally

But possibly more important than digestive issues, this calcium is scientifically proven to actually increase bone density. 2 published clinical studies show participants doing so within 6 short months! (5)

At first, some in the scientific community were sceptical, answering with a common refrain: ‘calcium is calcium’ – meaning all calciums have exactly the same effect on you once in your bloodstream.

But these body friendly algaes are much more than just calcium.

It believed that it’s all the extra trace minerals the algaes naturally contain (on top of the calcium itself), that is leading to these unheard of study results.

Because our bones are made up of much more than calcium. They are also made up of countless other trace minerals like vanadium, manganese, silica and others. All of which are provided by these unique body friendly algaes.

Another reason calcium from marine algaes is actually increasing bone density may have to do with the fact that simply our bodies were not designed to eat rocks!

Getting your calcium from living natural food sources like marine algaes is always recommended, versus from inorganic supplements.

To Supplement or Not?

We’ve all know that it’s best to get your nutrients from living food as opposed to synthetic, or rock sources. But the problem is we routinely eat nutrient poor fast and processed foods. And when we do eat well and at home, broccoli for instance (and other ‘good’ sources of calcium) is only about 8% calcium (and falling every year due to mass production techniques).

In an ideal world of only organic fresh foods, we would have all our nutritional needs met.

But because you probably make some dietary compromises or indulgences, supplements are a smart and affordable option to make sure we come don’t up short on vital nutrients.

Bone builder pack

Want to stop bone loss? The fastest way to REVERSE bone loss and INCREASE bone density is by using AlgaeCal Plus and Strontium Boost – non-constipating, organic plant calcium with vitamin D3, magnesium & vitamin C to maximize calcium absorption and K2 for a healthy heart. AlgaeCal Plus is clinically proven to build bone density and strengthen your bones…


  1. http://www.boxingscene.com/nutrition/36083.php
  2. http://en.wikipedia.org/wiki/Peristalsis
  3. http://www.healthaliciousness.com/articles/foods-high-in-magnesium.php
  4. http://www.betterhealth.vic.gov.au/bhcv2/bhcarticles.nsf/pages/Constipation
  5. https://www.algaecal.com/algaecal-info/algaecal-clinical-study/
gina richards

Thank you for the information. i have been prescribed the powdery chewable tablets that you describe as ‘rock’ for all the years since diagnosis by scan in jan 2006 age 50. i most certainly will try algae cal. also thank you for the dietary info, i will be following a healthier diet from now on. some of your diet plan was already on my weekly agenda, but now i have seen some that i could introduce for variety. much appreciated.


Anytime, Gina.

We’re here to help. Let us know if you need anything else, OK?


Hi there I have been taking calcium citrate and magnesium glycinate and I am having severe constipation. I was wondering if the calcium in the article would work for me. I can’t goon this way with severe constipation.
Thanks, Kathy


Hi Kathy,

AlgaeCal is a plant-based calcium so you should not get any side effects such as constipation.You can try AlgaeCal and if you experience constipation you can call us within 1 month and we offer a full refund on the opened bottle minus the shipping costs.

– Monica from AlgaeCal

Jan cutler

I think you have Just solved my problem! Where can I purchase AlgaeCal? Currently I am taking 1 , 60g calcium plus w/ magnesium in the am and one in the pm plus an am vitamin D , 1000iu.

Thank you


Can you by this in the uk?


Hi Sarah,
You cannot buy AlgaeCal in stores, but you can buy AlgaeCal online and we ship to the UK. For more information on international shipping go here: https://www.algaecal.com/shipping-returns/

– Monica from AlgaeCal

Nikki DeSimio

Hi,I would love to try AlgaeCal but I have a difficult time swallowing pills. Are they large?


Hi Nikki,
You can actually pull apart AlgaeCal capsules and sprinkle the powder into foods like yogurt, oatmeal and drinks like juices and smoothies if you find swallowing them difficult.
– Monica @ AlgaeCal

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