The Calcium – Magnesium Relationship

Read the related post Magnesium – Women Do You Get Enough?

This post sheds light on magnesium’s partner – calcium. These are major minerals that are needed together for your body to function. They work collaboratively – for example, calcium helps your muscles contract, and magnesium helps them relax.

There’s some myths and truths about these two minerals to shed light on . . .

osteoporosis, calcium, magnesium, osteopenia, nutrition, bone density, functional medicine, Dr. Laura Paris

Women need to supplement 1000-1200 mg of calcium

Probably not. The recommended amount of calcium varies between countries and eras. For example, it’s 1000-1200 mg for women in the U.S. today, however, it used to be 800 mg. In the UK it’s currently 700 mg. You may have been taught that you need 1000 mg of calcium per day for your bones, but it’s more complex than that.

This amount came from weak short-term studies. The idea was if you kept calcium levels high in your blood, it would prevent it from leaving your bones. But it turns out that too much calcium in your blood (from supplements) may cause it to deposit in areas where you don’t want it – into artery walls, kidney stones, and arthritic bone spurs.

There’s much more involved in bone-building than filling up on calcium!

Calcium from food is safe

True. We know calcium is needed, and that some populations don’t get enough from food. But, high-dose supplements don’t look good, and the jury is out on how much calcium is enough. This being the case, right now it makes sense to get most (or all) of your calcium from your diet. This is not too hard, considering these portions of foods that contain a decent amount of calcium:

Sesame seeds 0.25 cup 351 mg
Sardines with bones 3.75 oz can 351 mg
Yogurt 1 cup 296 mg
Collard greens 1 cup 268 mg
Spinach 1 cup 245 mg
Cheese 1 oz 201 mg
Turnip greens 1 cup 197 mg
Canned salmon with bones 3 oz 188 mg
Molasses 1 TBS 180 mg
Mustard greens 1 cup 165 mg
Beet greens 1 cup 164 mg
Bok choy 1 cup 158 mg
Almonds 2 oz 150 mg
Cow’s milk 4 oz 138 mg
Swiss chard 1 cup 102 mg
Kale 1 cup 94 mg

See? A cup of yogurt with 4 oz of almonds and you may be good to go! If you don’t eat dairy, switch out the yogurt for a tiny serving (1 cup) of collard greens.

Some populations need more calcium

Probably true. This can include:

  • Those with poor absorption from gastrointestinal issues.
  • Lactating women.
  • Pregnant women in their third trimester.
  • Women with osteopenia.
  • Women who enter menopause early.
  • Those who take acid-blocking medication or other meds that lower calcium.
  • People under 25 and over 70.

So for these populations, besides emphasizing dietary calcium, taking a low-dose supplement may make sense. Think 500 mg from food and 500 mg from a supplement (in 2 divided doses), to be safe. However, I do not recommend taking calcium supplements without sufficient magnesium, as well as the fat-soluble vitamins that orchestrate calcium metabolism (A, D, and K).

Calcium and magnesium should be in a 2:1 ratio

Not necessarily. This idea came from French magnesium researcher Jean Durlach. He really meant that this ratio should not be exceeded, as in don’t eat or take more calcium than double your magnesium intake. He didn’t mean this ratio is ideal.

We know that dietary magnesium deficiency is an epidemic. And magnesium is absolutely necessary to balance, or “soften” calcium. Think of these partnerships:

Outside your cells Inside your cells
Excites your nerves Calms your nerves
Contracts your muscles Relaxes your muscles
Clots and heals Keeps blood flowing freely
In hard structures – bones and teeth for support In soft structures – bone matrix for flexibility

Consume calcium and magnesium separately or they cancel each other out

True and false. There’s no evidence that calcium and magnesium from food interfere with the absorption of either mineral, so no worries with food sources.

If you take supplemental calcium and magnesium together, and one is a high dose (above approximately 250-300 mg), then yes it can compete for absorption with its partner mineral. So high magnesium with low calcium can lower calcium. And high calcium with no/low magnesium can lower magnesium.

What is the calcium/magnesium solution?

  1. Get at least half your calcium from food, and don’t supplement more than 400-500 mg in divided doses.
  2. Take an equal amount of magnesium (as magnesium is hard to get from food alone). For example, 200 mg of each mineral with breakfast and dinner.
  3. If you need even more magnesium, then take it alone, before bed.
  4. Don’t forget your fat-soluble vitamins!

I welcome your input below,

paris healing arts, doctor laura paris, dr. laura paris, dr laura paris

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  1. Thanks. This was a very good explanation of the calcium/magnesium relationship and answers a lot of the questions I had about it. I am going to print it up so I can easily refer back to it.

    1. I’m glad you found it helpful Janet. I have been meaning to figure out how to add a “print” option. Also please share with anyone you think may be interested. Thanks!

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