Anti-Aging Health

Cal/ Magselect : The why’s and why nots of calcium supplements

By Kim Crawford, M.D. Last updated: February 16, 2018

Benefits of magnesium + calcium together :

calcium supplementation needed If you choose to take calcium supplements, look for one that will allow you to take calcium with magnesium like Cal/ MagSelect.

When these two minerals are combined they offer the best benefits for osteoporosis prevention.



However there is sometimes a downside to calcium supplementation so read on to get all the facts.You can prevent osteoporosis with much less supplemental calcium then you are likely taking.


Calcium is important to prevent tooth decay and osteoporosis as well as activating fibrin to prevent excessive bleeding. With magnesium added,(Cal/ MagSelect)  these two help regulate your heartbeat, nerve conduction, muscle contraction, and muscle tone.

  • The average level of magnesium  in a body weight of 154lb is 19grams.
  • 25 percent of this amount is in the muscles, 65 percent in your bones and teeth, and the remaining found throughout your body tissues and blood.
  • Magnesium helps enzymatic reactions in the body and energy production.
  • With calcium, they both create a balance in muscle contraction (magnesium relaxes them while calcium contracts them).


Sources of Calcium and Magnesium

You can find dietary sources of magnesium and calcium in variety of foods.

It is important to understand that some sources in your diet can interfere with calcium and magnesium absorption: diets rich in chocolate and high in oxalic acid (beets, rhubarb, spinach), tea, coffee, whole grain products, and even fiber-rich foods will interfere with calcium absorption.

Yes, I know many of these are foods that give you energy or are metabolism boosting foods but you just need  to think of timing.

What Makes Calcium Supplements Potentially Dangerous?

Calcium is not a mineral that your body naturally makes. It is lost daily through your nails, sweat, skin, hair, and elimination. Replacing this loss is important. Research has estimated that our bodies excrete around 100 mg per day, with current recommendations for men and women currently being questioned greatly as being way too much supplemental calcium.

  • There are plenty of diets around the world that lack the calcium found in dairy and calcium supplements.
  • Those cultures find  calcium in plant based sources and they have no signs of osteoporosis.
  • The majority of the calcium in your body is stored within your teeth and bones, and if there isn’t enough your body will use the calcium reserves in your bones to perform important metabolic functions.
  • This is one of the main reasons why calcium supplementation is supported.
  • However, this prevention of calcium loss in the bones lacks any real evidence in modern medical studies.

The truth is that when calcium is taken in excessive amounts without any nutrients like vitamin D and magnesium to keep your body in balance, it can have an adverse effect.

You should never take more than 300 mg of calcium at once.

Even taking calcium supplements with vitamin D in excess of 300 mg of calcium even when the calcium is combined with magnesium has been PROVEN to be deleterious.

How?  More than what we have in our Cal/ Magselect of 300 mg per dose is too much calcium supplementation to be circulating in your bloodstream at once. Sorry to keep mentioning our product- just remember the amount that’s safe. 

Take more and It ends up on wet coronary placques and causes a “cementing effect” in forming arterial plaques. This has been proven over and over again.

So the big takeaway here is DO NOT TAKE more than 300 mg of supplemental calcium of any type at one time.

I don’t care WHAT your doctor is telling you-he/she is just plain out of date and THIS is the current literature,not the old 1000-1500 mg dosing at once which I told patients to do 20 years ago too!

If you DO supplement (fine if you are not getting a steady 600 mg/day total from diet)  the safest is calcium malate with magnesium malate in a 2:1 ratio and you must also take vitamin D. You vitamin D should have vitamin K in it for optimal absorption of IT. Side note-read what I’ve written about Vitamin D-everyone is deficient and low D is associated with heart disease, cancer, auto-immune disease and more.

The Best Forms of Magnesium

Magnesium citrate – Inexpensive and easily absorbed. Can be used as a constipation aid due to being a mild laxative.

Magnesium taurate – Best choice for individuals with cardiovascular issues to prevent arrhythmias and protect the heart. Easily absorbed and has no laxative effect.

Magnesium malate – Great choice for those that suffer from fatigue as it contains malic acid- which plays a large role in ATP synthesis and energy production. It is also high soluble and adds valuable brain health benefits. (The benefits for the brain and fatigue are even better if magnesium threonate is added.) BTW Mag Malate is what is in our Cal/ MagSelect

Magnesium glycinate – One of the most absorbable, safest and bioavailable forms of magnesium and least likely to create laxative effect.

Magnesium chloride – Best form of magnesium for cell and tissue detoxing, aids in kidney functioning, boosts the metabolism a little, and is easily absorbable.

Magnesium carbonate – Good choice for people that suffer from acid reflux and indigestion as confers antacid benefits.

Dietary Sources:

Magnesium can be found in green vegetables (celery, green beans, turnip greens, Swiss chard, broccoli, and mustard greens), flax seeds, sunflower seeds, sesame seeds, and pumpkin seeds.

 Common Types of Calcium

Calcium Carbonate- Not high in bioavailability and requires extra stomach acid in order to be absorbed. This is one of the cheapest and most popular forms of calcium supplements on the market. And it’s likely the most cardio-toxic. Just plain avoid it and read all your vitamin and mineral supplement labels to make sure it doesn’t contain it. Yes this is what TUMS uses to neutralize your stomach acid.

Calcium Citrate- Calcium citrate has an acidic base allowing it to be better absorbed than any other source of carbonate form. However, it has low bioavailability and less elemental calcium concentration.

Oyster Shell Calcium- A more natural form of calcium that is risky to take due to quality control and levels of lead toxins that have been found in it. This should absolutely be avoided.

Calcium Gluconate- Low levels of calcium concentration which requires a larger amount to consume to reach calcium requirements. The bioavailability is questionable.

Calcium Lactate- Found in foods such as baking powder and aged cheese. Has a medium bioavailability in the body due to being absorbed at different Ph’s.

Calcium Phosphate- This form of calcium is found in cow’s milk, but in supplement form it does not seem to be readily bioavailable.

Calcium Malate- Water soluble and high levels of bioavailability. Also shows evidence of being dissolved into cell membranes. Found in our Cal/ MagSelect.

Calcium Orotate– Another very  effective form of calcium supplementation.

Dietary Sources of calcium:

The best foods filled with calcium are leafy green vegetables, sesame seeds, carob, wheat-grass, wild caught salmon, bone broth, various citrus fruits, and organic grass fed and finished raw milk and cheese from pasture- raised cows, and let me single out of the leafy greens-raw spinach.

 Ratios of calcium and magnesium to take:

  • Some sources state that calcium and magnesium oppose each other at the intracellular level, but until essential trace elements are measured it is impossible to calculate a exact ratios.
  • Magnesium levels cannot be measured on standard blood tests-24 hour urine tests are needed and even those are of questionable accuracy.
  • BUT if you have read my article on magnesium we are a nation with up to 85% of us having a deficiency state.
  • Diets, supplements, current health status, past/current drug or alcohol use, and much more all have an impact on someone’s calcium and magnesium ratio and mineral status.
  • This makes it even harder to create a fixed ratio that all patients should use. However the majority of studies cite a calcium to magnesium ratio of 2:1 for most people.

This is why we have this ratio in our Cal/ MagSelect. Remember this ratio when shopping around.

As I just mentioned almost everyone is magnesium deficient, and it’s such an important mineral. Magnesium is needed to make energy, RNA, DNA and proteins. It is the structural part of a healthy bone. Diets today compared to over a hundred years ago have decreased dramatically to less than 200mg per day of magnesium because of how food is grown now. Magnesium is also easily lost from exercising, taking drugs, during times of stress (high cortisol), taking stimulants, drinking caffeine, smoking and more.

When an individual is deficient in magnesium a variety of symptoms can occur: anxiety, depression, fatigue, high blood pressure, heart palpitations, insomnia, muscle cramps, sensitivity to bright light and loud noise, panic attacks, restless legs syndrome, constipation and fibromyalgia.

These are the most common symptoms and magnesium deficiency is a casual factor.

This was talked about at length in the article solely dedicated to magnesium, where it’s found that up to 80% of Americans are deficient so please check out that article to see if YOU have magnesium deficiency symptoms.

Final notes:

Magnesium and calcium together play a large role in your health. Most people have a much larger ratio of calcium to magnesium for supplements which can affect them adversely in the long run. As research expands and as it states in this article, calcium supplementation with more than 300mg at a time can cause serious problems.


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