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Calcium Deficiency Symptoms: 17 Signs To Watch Out For

Calcium is arguably the most important nutrient in your body.

More than 99% of your calcium is stored in your bones and your teeth, which supports skeletal function and structure. The rest of the calcium in your body is used for other critical functions such as muscle contraction, blood vessel contraction and expansion, and sending messages through the nervous system.

But even though it’s one of the most critical minerals for your health, most people are still not getting enough. In fact, one study suggests as much as 68% of the American population is calcium deficient.

Adolescent girls and boys, women over 50, and men over 70 are at a particularly high risk of not meeting their daily calcium requirements. Menopausal women, vegans, and anyone with a dairy intolerance are also more prone to calcium deficiency than the general population.

What is Calcium Deficiency Disease?

Calcium deficiency disease, known as hypocalcemia, is a global health problem. People around the world are simply not getting enough calcium from their diets. This is particularly problematic in developing nations where food sources may be scarce.

When you have low calcium intake, you increase your risk of developing diseases like:

  • Osteopenia: Bone loss or bone thinning beyond the normal range is known as osteopenia. It’s a precursor to osteoporosis and is officially marked with a T-score between -1 and -2.49. T-scores are calculated as a part of DEXA scans, which measure bone mineral density.
  • Osteoporosis: Excessive bone density loss resulting in a T-score of -2.5 or lower is categorized as osteoporosis. Bones become weak and brittle and put you at an increased risk of fracture.

If your body doesn’t get enough calcium to keep its base functions running smoothly, it will leach calcium from your bones to make up for the shortfall.

If this goes on for long enough, your bone mineral density will deplete to the point of osteopenia or, worse, osteoporosis.

Since calcium is so critical throughout the body, low calcium symptoms can show up anywhere. And they can manifest in many different ways.

Signs and Symptoms of Calcium Deficiency

Calcium deficiency symptoms vary from mild to severe, if left untreated. But even if you don’t have any obvious signs associated with low calcium, especially early on, metabolic changes and potential dysfunctions may have already begun.

calcium deficiency signs and symptoms infographic

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Minor calcium deficiency symptoms can include:

  • Numbness
  • Tingling Fingers
  • Muscle cramps
  • Lethargy
  • Poor appetite
  • Weak or brittle fingernails
  • Difficulty swallowing
  • Fainting

More severe calcium deficiency symptoms can include:

  • Mental confusion, irritability, depression, and anxiety
  • Tooth decay
  • Insufficient blood clotting
  • Bone fractures
  • Osteopenia or osteoporosis
  • Growth and development delays in children
  • Heart problems involving blood pressure and heart rhythms

The US Surgeon General warns that by 2020, 50% of people over the age of 50 will be at risk for osteoporotic fractures. That’s right –– half of the entire 50+ population is at risk of breaking a bone.

America is one of the top sufferers from osteoporosis in the world, and the age to start getting concerned is getting younger and younger. Why, you ask? Look at the following major governmental studies.

From 1982–86, the US Food and Drug Administration (FDA) conducted the “Total Diet Study.” The study found several age and gender groups deficient in calcium, magnesium, and several other minerals important to bone health.

In 1996, the US Department of Agriculture (USDA) completed its “Continuing Survey of Food Intakes of Individuals,” which corroborated the FDA’s study. The USDA found both men and women of all ages were deficient in calcium. The most shocking statistic was for teen girls; 87% were not meeting their recommended daily intake of calcium.

The National Institutes of Health compares bone growth in children like depositing money in the bank for when you’re older. During childhood and into early adulthood, more bone is deposited than withdrawn as the skeleton grows in density and size. So the more you build up in your formative years, the longer you’ll have a supply to draw from as you age.

But how can you know if you’re calcium-deficient? A 24-Hour Urine Calcium test is the optimal lab for people concerned about their rate of calcium/bone loss. Talk to your doctor about this test to establish your calcium baseline and give you an idea of how much more you need.

Causes of Calcium Deficiency

Calcium deficiency doesn’t happen overnight. It can take years to manifest as physical symptoms, so by the time a deficiency becomes obvious, the damage is already done.

Before low calcium symptoms appear, keep these causes in mind:

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Lack of Calcium

This is a bit of an obvious one, but low calcium intake over a long period of time is a primary cause of calcium deficiency. How do you know how much calcium is enough? It’s recommended that adults over the age of 19 consume between 1,000–1,200 mg every day, depending on your gender.

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Prescription Medications

Certain medications may decrease calcium absorption by interfering with your body’s ability to absorb nutrients. In particular, drugs like PPIs, lipid-lowering statins, diuretics, anticonvulsants, and corticosteroids have been linked to reduced calcium and vitamin D levels. For a more thorough look at drugs that can cause bone loss, check out our blog post on the top 12 prescription drugs that cause osteoporosis.

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Dietary Intolerance

People with lactose intolerance or a dairy allergy are missing out on a whole calcium-rich food group and may struggle to find enough adequate dietary sources of calcium. Gluten sensitivities and celiac often lead to inflammation and malabsorption of nutrients and the subsequent risk of bone loss. To help find calcium-rich foods that fit your lifestyle, we’ve created a guide to some of the best plant and animal-based calcium food sources.

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Genetic Factors

Vitamin D-resistant syndromes are caused by hereditary defects or mutations in the vitamin D receptor. Impaired vitamin D receptors can have a direct impact on the body’s ability to absorb calcium. Inherited disorders of calcium and phosphate homeostasis can also cause bone loss and calcium deficiency. Evaluating organ systems and hormone levels will help with the diagnosis process and guide treatment options.

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Calcium absorption refers to the amount of calcium absorbed from the digestive tract into your body’s circulatory system. Another term for this is calcium bioavailability. Calcium absorption can be affected by the amount of calcium in your body, your vitamin D, and K2 levels, your magnesium and trace mineral status, age, pregnancy, and even certain plant substances in your diet. The amount of calcium consumed at a time can also affect absorption. For example, the efficiency of calcium absorption decreases as the amount of calcium you consume at a meal increases. A good rule of thumb is to not take more than 500 mg of calcium at a time because the absorption becomes quite low on any amount above that limit.

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Infants and children absorb as much as 60% of the calcium they consume. But once you reach adulthood, your absorption slowly decreases to about 15–20%. If you’re only absorbing 15–20% of the calcium you are consuming, it’s difficult to get enough through diet alone.

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Hormonal changes

A decline in estrogen during menopause causes women to lose bone density more rapidly. Postmenopausal women have about one-tenth of the estrogen levels that premenopausal women have. Meanwhile, low parathyroid hormone levels also impact your body’s ability to absorb calcium effectively.

Calcium is –– and always will be –– crucial for bone health. But when it comes to strong and healthy bones, other critical nutrients need to be taken with calcium for optimal health benefits.

These are:

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Vitamin D

Calcium and vitamin D work really well together. When you take vitamin D, you increase your body’s ability to absorb calcium effectively. Lara Pizzorno, the author of Your Bones, says, “Less widely known is that vitamin D also boosts the expression of the vitamin K-dependent proteins. So when you take supplemental vitamin D, you are increasing the amount of calcium available in your body and, therefore, your need for vitamin K.” In other words, vitamin D increases the amount of calcium you absorb, but in turn, also increases your need for vitamin K.

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Vitamin K2

Don’t mix this up with vitamin K1. Vitamin K2 has nothing to do with blood clotting factors. And it’s very difficult to get without supplementation. It’s not in leafy greens like K1 and is found only in tiny amounts in eggs and cheeses. Its main role is to regulate calcium deposition. Meaning, vitamin K2 cleans calcium deposits from your arteries and moves it to your bones. Talk about important!

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It’s reported that as many as 80% of Americans are magnesium-deficient! Deficiency of this mineral affects bone building, bone fragility, and alters calcium metabolism and the hormones that regulate calcium.

How is Calcium Deficiency Diagnosed?

Hypocalcemia can be caused by low vitamin D levels leading to poor calcium absorption, or because of reduced parathyroid hormone function. Low parathyroid hormone levels lead to excessive calcium loss through the kidneys and reduced intestinal absorption of calcium.

Because many symptoms of hypocalcemia are obvious, your doctor will first make a clinical assessment of any symptoms, like muscle spasms. One spasm in particular — Trousseau’s Sign, a hand spasm brought on by inflation of a blood pressure cuff — is a good indicator. That’s because it’s present in 94% of hypocalcemic patients and only 1% of non-hypocalcemic people.

Longstanding hypocalcemia is associated with neuropsychiatric symptoms (depression, anxiety, euphoria, psychosis, etc.), cataracts, and even intracranial pressure (pressure buildup inside your skull).

It should also be noted that gradual hypocalcemia is less likely to have obvious outward signs than if your calcium levels are suddenly and rapidly depleted.

Beyond observational diagnosis, your doctor will look at your blood work to check your calcium, vitamin D, and parathyroid levels. The most accurate vitamin D test is the 25-hydroxyvitamin D blood test. Optimal blood levels of 25OHD are 50-80 nanograms per mL.

Your doctor will also ask about your medical history as hereditary conditions can play a role in developing hypocalcemia and osteoporosis. They may also recommend a DEXA scan depending on your age to assess your bone mineral density.

How to Prevent and Address Calcium Deficiency

Hypocalcemia is easy to address and prevent and generally involves adding more calcium to your diet. But your treatment plan will ultimately depend on the severity of your calcium deficiency and should be discussed with your doctor.

As far as prevention goes, it’s never too early to start. Focus on eating calcium-rich foods with plenty of bone-friendly nutrients. And definitely check out the recipe section of our blog for quick, easy, and delicious bone-healthy recipes the whole family can enjoy.

After peak bone mass, which most people reach around age 40, you begin to lose 1% of your total bone mineral density each year. Your absorption of vitamins and minerals also declines as you age. That is why recommendations for dietary calcium intake are higher if you’re 51 and older.

And yet, even with everything we know about the consequences of calcium deficiency, research shows that as much as 68% of Americans still have a low calcium intake.

So to ensure you are getting enough, try AlgaeCal Plus. AlgaeCal Plus is a natural, whole-food supplement with the ideal blend of vitamins and minerals that work with your body to not only maintain bone density but actually build new bone. AlgaeCal’s plant-based calcium naturally contains all 13 essential bone-building nutrients and is specially formulated with vitamin D3, vitamin K2, and boron.

Author: Monica Straith, BS

Monica is the PR and Outreach Manager and Fitness Lead at AlgaeCal. She’s an ACE Certified Personal Trainer and Nutrition Specialist, and has a B.S. and B.A. from the University of Wisconsin-Madison, where she played varsity soccer for four years. Monica pulls from her experience in athletics and health to contribute to AlgaeCal and has also been featured on myfitnesspal blog, Prevention, and Huffington Post.