All you need to know about testing Calcium levels with a laboratory test
7.8% of people tested have Calcium levels which are too high.
And 3.8% have levels that are too low.
The average Calcium result is 2.4 mmol/L
Note what is normal for you may differ for your age and sex.
Nearly all (99%) of your body's calcium is found in the bones. The rest circulates in your blood in both 'free' and 'bound' forms.
This test measures for the total amount of calcium in your blood and can indicate low (hypocalcaemia) or high (hypercalcaemia). Both low and high levels are associated with a number of conditions related to Vitamin D, parathyroid gland, kidney disease or bone diseases.
By buying a laboratory test kit with professional nurse or clinic collection, you can accurately measure Calcium for total reassurance.
Professional analysis in an accredited laboratory ensures rapid result delivery.
The Vitall Vitamins & Minerals Complete nurse or clinic test kit includes a Calcium test and is available for just £99.00.
Tests which include a Calcium test:
High calcium levels are known as hypercalcaemia, meaning there is too much calcium in the blood. Around half of the calcium in the blood is bound to the protein albumin, so calcium levels are often considered alongside albumin levels.
There are a wide range of causes of high calcium, including high parathyroid hormone levels, bone cancers (both primary bone cancers and other cancers that spread to bone), and other disorders such as sarcoidosis. This finding is often reviewed further to clarify the cause.
High calcium levels can be associated with a range of symptoms, including severe dehydration. This level is generally treated as clinically significant and is often prioritised for early review.
Low calcium, also called hypocalcaemia, means there is not enough calcium in the blood. The most common cause is low protein levels, especially low albumin, and calcium results are often looked at alongside albumin.
Other possible causes include low dietary calcium, vitamin D deficiency, magnesium deficiency, and conditions such as chronic kidney disease, chronic gastrointestinal disease (which can result in malnutrition and diarrhoea), or bone disease.
Calcium is important for maintaining bone growth and is particularly relevant after menopause, when low bone mass can occur and osteoporosis risk can increase. Diet is often sufficient for calcium intake, and low vitamin D is a common cause of low calcium levels; supplements such as vitamin D are sometimes considered. Discussion with a doctor can help weigh the risks and benefits of starting supplementation.
Measure your Calcium levels and fully identify & optimise nutritional deficiencies with a Vitamins & Minerals Complete nurse or clinic finger-prick bloodtest kit
You get the convenient testing with the reassurance of professional clinical analysis. Your results are delivered quickly & securely online.
This Vitamins & Minerals Complete Test is advised if you:
Calcium is an essential mineral that is the main component of your teeth and your bones. Almost all (99%) of the calcium in your body is stored in your bones. When your blood calcium levels are low, which can be measured using a home calcium blood test, your body acts in such a way as to draw calcium out of your bones in order to increase blood calcium levels. Likewise, when your blood calcium levels are high, your body tries to eliminate them through your urine and stool, or they are stored in your bones.
Calcium plays a key role in the contraction of your muscles: when your muscles are stimulated by a nerve, calcium triggers the contraction process. Calcium also plays a very important role in the blood clotting process, which directly affects your heart and blood vessels. Your calcium levels also affect your blood pressure, cholesterol levels and digestive health [1,2].
Your body cannot produce its own calcium, so you need to have a calcium-rich diet. Your calcium levels also depend on your hormone levels (parathyroid, oestrogen, calcitonin), your phosphate levels and your vitamin D levels. Vitamin D helps your body absorb calcium, and these two nutrients go hand in hand in maintaining good bone health and growth during childhood.
Therefore, no matter how much calcium you get through your diet, you need to be having a sufficient amount of vitamin D as well, either from nutrient rich foods, or from sunlight exposure. Good examples of food with a lot of calcium are dairy products such as milk, yoghurt, and cheese, as well as leafy vegetables such as kale, broccoli, and spinach, soybeans, and sardine [3].
Your body tends to get rid of calcium quite easily, so it is important to check your calcium levels every once in a while with a calcium blood test. If your calcium levels fall below a certain threshold, your body will start to take the calcium it needs from your bones, which can cause serious problems on the long term such as osteoporosis where your bones become more fragile and are more easily prone to fractures.
If you are a post-menopausal woman, you are at a greater risk of having a calcium deficiency due to your decreased oestrogen levels, therefore you are also at a greater risk of developing other conditions such as osteoporosis.
Calcium supplements can also help you maintain healthy calcium levels and can be prescribed by your doctor based on your calcium blood test results, particularly if you are a post-menopausal woman, or if you don’t eat dairy products [1,4].
Calcium levels change over time and a normal calcium level at 60 years old will not be normal at 25 years old. Between the age of 0 and 10 years old, your calcium levels are between 8.7 to 10 mg/dl and are slowly increasing during this period.
Calcium levels start to increase more quickly between the age of 10 and 15 years old, an important period for growth, reaching a peak between 15 and 25 years of age to around 10.7 mg/dl.
From this moment on calcium levels will decrease slowly and are in the range of 9 to 10.4 mg/dl by the age of 30 years old.
Above the age of 40 years old, your calcium levels will start to decrease very slowly, remaining between 9 to 10 mg/dl during adult age. For example, if you happen to have calcium levels at 10.5 mg/dl but you are more than 40 years old, although this might be in the normal range for an adolescent, these levels could indicate an underlying health condition.
The Vitall home calcium blood tests always include the appropriate ranges for someone of your age and sex, to ensure abnormal calcium blood levels can be detected [5,6].
If you have low calcium levels, this is also known as hypocalcaemia. Having hypocalcaemia for long periods of time can lead to dry skin, weak nails, and damaged hair.
You can also experience muscle cramps and over time hypocalcaemia can affect brain function, leading to confusion, depression, delirium, and hallucinations. In more severe cases, hypocalcaemia can lead to muscle spasms which can lead to difficulty breathing, irregular heartbeat and seizures.
Given these potentially serious outcomes, measuring your calcium levels on a regular basis with a calcium blood test is recommended [7–9].
Low calcium levels (hypocalcaemia) mean you have low levels of calcium in your blood, and can be detected using a home calcium blood test. Usually, a calcium deficiency is more common than having too much calcium in your blood, and this can be treated by taking calcium supplements and also attending to any underlying medical conditions that might be causing it. You should ensure to discuss this with your GP first.
Hypocalcaemia can occur as a result of either not enough calcium being drawn from your bones into your bloodstream, or when excessive amounts of calcium are lost in your urine. This can be due to medications such as certain diuretics, corticosteroids, bisphosphonates (used to treat osteoporosis) and others. It is important to monitor your calcium levels on a frequent basis when taking drugs that can cause hypocalcaemia as a side effect.
Other reasons for having hypocalcaemia could be vitamin D deficiency, low magnesium levels, not having a diet rich in calcium, inflammation of the pancreas, or a kidney dysfunction. If you have low levels of parathyroid hormone (hypoparathyroidism), this will lead to your blood calcium levels to fall as well, and your blood phosphorous levels to rise, which can cause muscle cramps and spasms.
You should contact your doctor if you are experiencing any of the symptoms related to low calcium levels, or a calcium blood test shows it is low, in order to determine the underlying cause [7,8,10,11].
Having high calcium levels in your blood is also known as hypercalcaemia, which can be detected with a calcium blood test. Hypercalcaemia can affect your kidneys which can lead to thirst and the need to urinate more often. Checking your kidney function with a home kidney function test can also be useful.
You can also experience nausea, vomiting, loss of appetite, constipation, belly pain, muscle aches and bone pain, confusion, tiredness, depression, and in the most severe cases heart problems such as palpitations, irregular heartbeat, fainting, and very rarely seizures or a heart attack [12–14].
Having high calcium levels in your blood (hypercalcaemia) can result from consuming too much calcium through your diet, or consuming too much vitamin D. The most common cause of hypercalcaemia is if your parathyroid glands are secreting too much parathyroid hormones (hyperparathyroidism), which will lead to higher levels of calcium in the blood.
Other causes of hypercalcaemia come from medications such as thiazide diuretics, as well as kidney failure, thyroid disease, and immobility. In more serious cases, cancer can lead to hypercalcaemia, typically lung cancer, kidney cancer, breast cancer, gastrointestinal cancer, leukaemia, and head or neck cancers.
If your calcium levels are too high, your doctor might carry out more blood tests to check your parathyroid gland activity in order to find the root of the problem [15–18].
Calcium blood tests are very useful because they provide important information that can allow you and your physician to detect and monitor conditions related to your bones, teeth, heart, blood vessels, blood cells, kidneys, nerves, digestive system, parathyroid glands, thyroid gland, and muscles.
A home calcium blood test can also be used to monitor the impact of drugs that can either increase or lower your calcium levels. Abnormally high or low calcium levels can potentially indicate the presence of an underlying medical condition, which can make your doctor ask you to take more tests to further investigate it.
Blood tests that can help your doctor better understand what is happening in your body are Vitamin D, magnesium, phosphorus, and parathyroid hormone levels tests. Your vitamin D and parathyroid hormone levels directly impact the levels of calcium in your bloodstream and can thus be the reason you have abnormal calcium levels [19,20].
You should routinely check your calcium levels – at least once every year using a calcium blood test. Your doctor may also ask you to take the test if you are showing symptoms of hypercalcaemia (too much calcium) or hypocalcaemia (not enough calcium).
A home calcium blood test can also help your doctor detect certain conditions like cancer, kidney disease, osteoporosis, parathyroid disease, or malnutrition. Some medications can impact your calcium levels, so it is important to know if you need to stop taking them before the test in order to obtain accurate results.
Drugs that can lower your calcium levels are bisphosphonates like zoledronic acid and alendronate, antiacids containing calcium, denosumab, cinacalcet, phenytoin and cisplatin. On the other hand, drugs that can increase your calcium levels are lithium, diuretics like hydrochlorothiazide, and Vitamin D supplements.
Another important point is to avoid having food or drinks that contain a lot of calcium before taking the test as it may affect the results [21,22].
If you want to find out your calcium levels, you can simply order a calcium home test kit online and have it delivered to your home. There are many test kits which can measure your calcium levels, for example a vitamin and mineral test kit, which gives you a summary of many vital vitamins and minerals that could be lacking.
If you are experiencing bone related problems or if you above the age of 50 or post-menopausal, you might want to take a bone health test, which can give you a summary of your calcium levels and other minerals, proteins and vitamins that play a role in bone health.
These calcium home test kits are carried simply by pricking your finger with a lancet to draw blood, then placing it in a prepaid envelope and sending it to the laboratory by post. Your results will be sent to you securely online, usually within the following 24 hours.
Whatever calcium blood test you take, we recommend also measuring your vitamin D levels at the same time, since the levels of these two biomarkers are often closely linked.
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Adjusted Calcium