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Why your Calcium Supplement May not be Helping Your Bones

Worried about bone loss? Here’s what busy women need to know about calcium-rich foods and supplements.

Milk does a body good, right? (Anyone remember that??) Milk is an excellent source of calcium, along with calcium-rich foods dairy and non-dairy foods. But you’re not actually absorbing 100% of that calcium.

Here’s what you need to know to prevent bone loss.

What's the Big Deal with Calcium?

Calcium is the most abundant mineral in the body, building and maintaining sturdy bones and teeth, helping muscles send messages to the brain and blood vessels shuttle blood throughout the body.

Calcium teams up with vitamin D to increase its absorption.

Bones: The Calcium Vault

The majority of your calcium stash—about 99% of it—is tucked away in your bones and teeth. Think oft hem as your body's bank vault, where calcium is the currency. As you grow, your body invests in your bones, and by the time you hit 30, you've pretty much reached your peak bone mass. 90% of peak bone mass is achieved by age 18-20 and is completed by age 30.

After menopause, women lose an average of 1% of bone mineral density each year. Bone loss slows down after 70, but it's still happening. 30% of post-menopausal women will have osteoporosis.

Which foods are highest in calcium?

Foods should be your first choice in meeting your calcium needs each day.

Of course, there’s dairy products like milk, yogurt and cheese.

Non-dairy foods have significant amounts of calcium too.

Canned sardines and salmon (with those tiny, edible bones)

Kale, broccoli, Bok Choi

Foods fortified with calcium in the US, like tofu (if it’s calcium-set), ready-to-eat cereals

Fruit juice – calcium citrate malate is a well-absorbed form of calcium in some fruit juices.

Is Calcium Hard to Absorb?

Age, level of stomach acid, disease, and medications can all affect calcium absorption.

Calcium Absorption – What Interferes with calcium absorption?

Certain compounds in plants like oxalic acid and phytic acid can form tricky bonds with calcium, reducing its absorption. Spinach, with all its healthy goodness, has an absorption rate of just 5%. Meanwhile, milk has a 27% absorption rate.

Caffeine, phosphorus, and low vitamin D levels can also join the "let's make calcium absorption harder" party.

How Much Calcium Should I Take at One Time?

Whether it’s from food or supplements, the body can absorb about 500 milligrams of calcium at a time. If your supplement has more than that, your body has to do something with the rest. It’s possible that the calcium could cause blood clots or calcium deposits on artery walls.

What Helps the Absorption of Calcium in the body?

There are a few things and conditions that can increase your calcium absorption.

Vitamin D is necessary to absorb calcium and sometimes it’s better taken with food and not on an empty stomach.

Should I Take a Calcium Supplement?

I believe in a food-first approach and a nutrient in pill form is not processed in the body the same way as from food.

There have been studies that found little, to no benefit, from taking a calcium supplement to prevent hip fractures. There have also been studies that have found that calcium supplements increase the risk of calcium buildup in the heart’s arteries.

That being said, you may need a supplement to meet your needs.

The two most common supplement forms are calcium carbonate and calcium citrate.

The actual amount of elemental calcium in each supplement is important because that’s what your body is absorbing.

The supplement label usually tells you the amount of elemental calcium in each serving, but you can figure it out, as well.

Calcium carbonate is 40% elemental calcium by weight. So, if your supplement is 1,000 mg of calcium carbonate, it contains 400 mg elemental (absorbable calcium).

Calcium citrate is 21% elemental calcium.

Which Form of Calcium is Absorbed Best?

Calcium carbonate should be taken with food for better absorption. (Since it’s solubility rate is lower.)

Calcium citrate is less dependent on stomach acid, so it can be taken without food, but, in general, absorption of supplements is greater if taken with food regardless of stomach acid.

Remember, one of the biggest factors in absorption is the amount consumed at one time. Absorption is best with intakes of less than 500 mg at a time. And absorption decreases as amount increases.

For example, you absorb 36% of a 300 mg calcium dose, but only 28% of a 1,000 mg dose.

Why Can't I Tolerate Calcium Supplements?

Some people have a harder time tolerating calcium supplements than others.

Smaller doses throughout the day can help reduce side effects like gas, bloating, and constipation.

(Which are worse with calcium carbonate supplements, especially if stomach acid is lower (like in older people and those on antacids.) Taking calcium supplements with meals or in divided doses also decreases side effects. (So, if you’d like to take a 500 mg calcium supplement each day, consider taking a 250 mg dose in the morning and a 250 mg dose in the evening.)

How do I Choose the Best Supplement?

Supplements’ safety and truthful claims are regulated by the Federal Trade Commission. Many products independently test their products and may bear a U.S. Pharmacopeia (USP) abbreviation, (CL) Consumer Lab, NSF (National Sanitation Foundation); they meet voluntary industry standards for quality purity, potency, and tablet disintegration or dissolution.

For some supplement recommendations that are third-party tested, visit my Fullscript Bone Health store HERE.

Can Too Much Calcium Supplement Cause Problems?

Although your body has a built-in regulatory process for calcium maintenance, disease and

overuse of food + supplements could cause high calcium levels.

You don’t want to consume more than the tolerable upper limit of calcium each day from food and supplements combined. This could increase your risk of kidney stones, constipation, prostate cancer, calcium buildup in blood vessels, and a decrease in absorption of zinc and iron.

So, stick to the RDA (recommended daily allowance) for calcium.

Calcium is your ally in the journey to healthier bones and a happier smile. Cheers to getting up off the toilet by yourself when you’re 90! :)

The information provided on this website in intended solely for education purposes and cannot

substitute for professional medical advice. Please consult with your physician or Registered

Dietitian Nutritionist.

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