Calcium Absorption— What Really Matters?

When it comes to calcium absorption, there’s a lot of contradictory information out there.

A quick internet search for “calcium supplements” will return a ton of results claiming one particular calcium is more absorbable than another. But anyone making these claims is either “marketing” their calcium, or falling prey to a common misconception…

Because the truth is, given the right circumstances, all types of calcium are absorbed very similarly. (We’ll go over what circumstances can affect absorption in a moment!)

Now, this may come as a bit of a shock because we’re so used to hearing about calcium in terms of absorption. But the problem is, when people talk about absorption, what they’re really talking about is “dissolution”.

Let’s have a look at the difference between the two!

Calcium Absorption vs. Calcium Dissolution

Some companies that claim their calcium is “better absorbed” are mistaking absorption for dissolution. Yet these are two very different mechanisms.

Dissolution is your stomach acid dissolving the calcium salt when first ingested.

Absorption is your intestines taking up the calcium after dissolution and sending it into your bloodstream.

Now, all calciums dissolve very well in stomach acid— 95-100% dissolution is normal. But the confusion occurs because people use this number in reference to absorption… which as we’ve seen, is a very different thing!

And when it comes to absorption, the science points in one direction. Studies show that all calcium salts absorb a few percentage points above or below 30%.

There’s no wild variation in absorption rates depending on your source of calcium. Calcium carbonate, calcium citrate, calcium malate… it doesn’t make a difference! There’s no calcium on earth that absorbs at 90% or at 5%. They ALL absorb at around 30%.

That said, just because all calcium types absorb around the same, it doesn’t mean they’re all made equal. As we’ll see in just a moment, it’s what happens after absorption that really matters.

But first, there are a few things that can affect calcium absorption.

What Factors Affect Calcium Absorption?

Although the source of calcium doesn’t affect absorption rates, there are a few factors that do! Here, we’ll review what to keep in mind to get the most out of your calcium supplements.

Take Your Calcium With Food

As we covered earlier, before you can absorb calcium, it needs to dissolve in your stomach. And to properly dissolve the calcium you consume, you need stomach acid! When you eat, you produce stomach acid which is why we recommend taking AlgaeCal with a meal or snack.

The one exception to the rule is calcium citrate. You don’t need stomach acid to dissolve this form of calcium which is why it’s recommended for people who’ve had gastric bypass surgery.

But remember, just because it dissolves easily, doesn’t mean it absorbs better! After dissolution, calcium citrate absorbs at the same rate as all other calciums.

Ensure You’re Getting Adequate Vitamin D

You may have heard that vitamin D is crucial for bone health, and here’s why: you need vitamin D to properly absorb calcium.

Without adequate vitamin D, your body can only absorb 10-15% of the calcium you consume. And this applies to all forms of calcium— whether it’s from food, calcium carbonate, calcium citrate, or any other kind of supplemental calcium.

Now, calcium is both actively and passively absorbed in the small intestine.

Active absorption is what scientists call “transcellular”. This means calcium passes directly through cells on its way to your bones.

Passive absorption, on the other hand, is “paracellular”. This means calcium takes a bit of a longer route and passes between cells.

But the amount of calcium you absorb passively is quite small compared to the amount you absorb actively! And you need vitamin D to actively absorb calcium. Which is why you can only get a fraction of the calcium you consume without it.

But what qualifies as “adequate” vitamin D? Well, studies show that an optimal blood level of vitamin D is around 250HD.

In one of these studies, researchers measured calcium absorption in two groups. The test group was pre-treated with vitamin D, while the control group was not. All participants received 500 mg oral calcium with breakfast, and blood was taken throughout the day to gauge calcium levels.

In the end, the group given vitamin D absorbed 65% more calcium than the control group! These results clearly demonstrate the importance of vitamin D for calcium absorption.

If you’re concerned about your vitamin D levels, it’s a good idea to get them checked with your doctor. Once you know where you stand, you’ll be able to make an informed decision on whether you need to supplement to maintain healthy vitamin D levels.

Take a Maximum of 500 mg of Calcium at a Time

Research shows that you absorb calcium most effectively in amounts of 500 mg or less. Amounts greater than 500 mg are poorly absorbed so it’s eliminated in your urine.

It’s worth noting that research also shows, for best results, you should take your calcium supplements in a dose of around 350 mg, twice daily.

To come to this conclusion, researchers looked at a sample of 37 men and women. They divided them into two groups: one group received 1000 mg of calcium all at once while the other group was given 300 mg.

Now, the subjects that received the 1000 mg were only able to absorb around 28.4% of the calcium from that dose. On the other hand, the group that received 300 mg, absorbed 36%. (Notice how these two values fall in the calcium absorption range of slightly above or below 30%!)

From these results, researchers determined that a dose of around 350 mg taken twice daily, may provide the best absorption of calcium. And that no more than 500 mg should be taken at a time. Think of it like this: you’re not overloading your small intestines with work that way.

Why Calcium Absorption Isn’t A Big Deal

It may seem intuitive that you’d want to absorb as much calcium as possible. And considering all the talk about “absorption”, it certainly seems that way! But this is another common misconception.

Here’s why:

Without excess calcium (calcium not absorbed into your bones) your body wouldn’t function properly. There’s a lot more to calcium than bone health. It plays a key role in vital biological processes outside your bones too.

So, excess calcium can actually be a great thing! According to the late Dr. Robert Heaney, arguably the world’s top calcium researcher, excess calcium can reduce prostate and colon cancer rate. It does this by combining with oxalates— an organic acid linked to many health problems including colon cancer. The calcium then carries these toxins out with your feces.

What’s more, calcium has been linked to positive health benefits like lower blood pressure and weight loss!

So, even if a hypothetical “95% absorbed” calcium supplement existed, you wouldn’t want to take it.

If you did, not only would the rest of your body miss out on calcium, but it would be calcium overload for your bones. Because just like not getting enough calcium can harm your bone health, getting too much can be harmful too.

Too much calcium can cause a nutrient imbalance. For example, it can trigger a magnesium deficiency. And without adequate magnesium, calcium can’t do its job properly… which defeats the purpose of taking calcium supplements in the first place.

So really, absorbing more calcium is beside the point. The focus should be on what a calcium supplement can do for your bone health, not on absorption. Which leads us to our next point: it’s what happens after absorption that really matters!

What Happens After Absorption Is What’s Really Important!

What you care about most is strong, healthy bones, right? So, what good does absorbing calcium do if you’re not building bone density?

This is why what happens after your body dissolves and absorbs your calcium supplement is the important part. Because after all this has taken place, you still need to make sure your body can use the calcium the way you want.

Now, we spoke earlier about how you need a bit of excess calcium in your body, but the main reason you’re taking a calcium supplement is to improve your bone health. So you want a large chunk of the calcium you consume to make its way to your bones.

This is where “helper” nutrients come into play. As we mentioned before, vitamin D is key for making sure you can absorb calcium in the first place. But there are a few more vitamins and minerals you’ll want to take note of as well.

Vitamin K, especially in its K2 form, is another vital ingredient for healthy bones. In fact, you could consume more than enough calcium, but without vitamin K2, you’d still have weak bones… because they wouldn’t receive any of that calcium!

Vitamin K2 activates two proteins that handle where calcium goes in your body. These two proteins direct calcium to your bones and keep calcium out of places you don’t want it (like your blood vessels and kidneys).

Magnesium is also essential for healthy bones— it keeps them strong and malleable with the help of other minerals like boron, copper, nickel, phosphorus, silicon, and zinc (all of which are found naturally in AlgaeCal!). But in terms of calcium, too little magnesium can affect absorption.

This is because magnesium impacts the amount of parathyroid hormones you produce. And parathyroid hormones regulate how much calcium your body absorbs.

The moral of the story is that calcium doesn’t work in isolation to strengthen your bones. You need a balance of many vitamins, minerals, and the right circumstances to increase your bone density. A fact that is made clear by calcium’s inability to build bone when taken by itself!

This is why AlgaeCal uses a multi-nutrient approach to bone health. AlgaeCal Plus contains all 13 essential bone-supporting minerals and clinical doses of magnesium and vitamins K2 and D3. The combination of these nutrients ensures that calcium is delivered to where you need it most: your bones.

What’s more, the strain of algae that AlgaeCal is sourced from, Algas Calcareas, actually contains all the bone-supporting minerals in the balance your body needs them— naturally! It uses these minerals to support its own structure, so they’re basically pre-approved to support your bones too.

And since AlgaeCal comes from a natural, plant-based source, it won’t cause any nasty side effects like stomach upset and constipation either!

Calcium Absorption Takeaways

At the end of the day, it’s not calcium absorption you should be worrying about. It’s increasing your bone density.

But because of marketing misinformation, “absorption” is chocked up to be more important than it is. Yes, you need to absorb calcium to build bone. But all calciums absorb the same, at around 30%!

Plus, even if a calcium supplement could offer 95% absorption, you wouldn’t want to take it…

Your body needs calcium that’s not absorbed for many other essential biological functions like fighting toxins and lowering your blood pressure. So, if you absorbed too much calcium, there wouldn’t be enough leftover for the rest of your body!

That said, there are some factors that can affect absorption like:

  • Whether you take your calcium with food
  • Your vitamin D levels
  • How much calcium you take at one time

But once again, ensuring you absorb calcium well doesn’t mean much, if it isn’t doing anything for your bone health. Which is why you need other essential minerals and vitamins with your calcium.

Specifically, vitamin D and K2, and magnesium (to name a few). These three nutrients help your body both absorb and use calcium to the best of its ability— and to the benefit of your bones!

Without these “helper” nutrients, you could take calcium supplements for years, and at best, you’d slow your bone loss. But when all the nutrients and minerals your bones need work together, then you can actually build bone density.

That’s why AlgaeCal’s multi-nutrient, plant-based calcium supplement is guaranteed to increase your bone density in as little as six months!