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Vitamin D Toxicity: Symptoms and Prevention

Updated: May 27

Vitamin D Toxicity: Symptoms and Prevention

It is one of the most important minerals in the human body. Known for improving mood, regulating heart health, bone health, and calcium usage. In most countries, vitamin D supplements are the most important supplement during winter days. During these cold days, sunlight exposure (the most common and natural source) is hard to find, which causes deficiency. Vitamin D deficiency may lead to fatigue, muscle dysfunction, bone pain, mood changes, and more.

But on the other side of the spectrum, we have vitamin D toxicity. Overdoses of vitamin D supplementation mainly cause vitamin D toxicity. In our blog on vitamin D supplementation, we already underlined the importance of staying within that 100mg range of recommended intake for teenagers. Oftentimes, suppliers are not aware of this. This leads us to the main topic of today: Vitamin D Toxicity.


In today's blog, we're diving into vitamin D overdose and therefore toxicity, its causes, symptoms, treatment, and even more importantly: prevention. We'll guide you through everything you need to know to prevent its nasty symptoms and how to get rid of it.


So before you open your jar of vitamin D supplementation and consume supplement after supplement, take a quick look at everything we discuss here!


Vitamin D Toxicity: Symptoms and Prevention

What is Vitamin D Toxicity?

Causes of Vitamin D Toxicity

Symptoms of Vitamin D Toxicity

Prevention of Vitamin D Toxicity

Diagnosing Vitamin D Toxicity

Conclusion

Frequently Asked Questions (FAQ)

 

What is Vitamin D Toxicity?

"Vitamin D toxicity comes from large doses of vitamin D supplementation, not by diet or sun exposure". The reason behind this is that both food and sunlight are way less concentrated than vitamin D supplements, which makes it easier for your body to digest.


An overdose of vitamin D can cause a buildup of calcium in the blood. The way the body regulates vitamin D from food and sun exposure is in fact the same as vitamin D supplementation, but the difference is made in the concentration of vitamin D in both food and supplementation. After the body acquires vitamin D from sunlight exposure, (fortified) foods, or supplementation, it gets stored in the body's fat cells. Here it remains inactive until needed.


A process called hydroxylation activates the liver and kidneys to turn inactive vitamin D into its usable form which the body needs.


Causes of Vitamin D Toxicity

The main cause of vitamin D toxicity? Exactly: extremely high doses of vitamin D in supplements. Let's take a look at some examples:


All of these vitamin D supplements contain 10.000IU, which is the equivalent of 250mcg. This is 2.5X the recommended amount of mcg for teenagers.


A general rule of thumb is to multiply IU by 0,025 to get the amount of vitamin D in mcg.


Okay, maybe we scared you a little too much. According to research, you'll need to consume 60.000 International Units (UI) or 1500mcg of vitamin D to get to vitamin D toxicity. This is 15 times more than the recommended amount of vitamin D for teenagers. In order to get here, you would need to consume 6 vitamin D softgels of the supplements listed on the right... Good luck with that.









Medical Conditions Influencing Toxicity

Some prescription medications cause an increase in vitamin D concentration in the blood, such as medications to treat high blood pressure and heart diseases. But also estrogen therapy, taking antacids for a longer period, and isoniazid (used to treat tuberculosis) can cause elevated levels of vitamin D in the blood.


If you're familiar with these conditions, hypervitaminosis D is always a thing you should be careful of. Always consult your doctor if you're not sure.


So, vitamin D toxicity comes from supplementing high-doses of vitamin D for a longer period of time. You are even more likely to develop hypervitaminosis D if you're familiar with any of these health problems:

  • Kidney disease

  • Liver disease

  • Tuberculosis

  • Hyperparathyroidism (a condition where one or more parathyroid glands are overactive, causing high levels of calcium in the blood)

  • Sarcoidosis (an inflammatory disease that causes the formation of granulomas (tiny clumps of inflammatory cells) in various organs, most commonly the lungs and lymph nodes)

  • Histoplasmosis (an infection caused by inhaling spores of the fungus Histoplasma capsulatum, which often affects the lungs and can spread to other parts of the body)


Symptoms of Vitamin D Overdose

Symptoms of Vitamin D Toxicity

Okay, so now we know what vitamin D toxicity is, where it comes from, and which medical conditions may influence the level of vitamin D in the blood, it is time to learn what the symptoms are of vitamin D toxicity.


Vitamin D toxicity mainly comes from either bad regulation or too much calcium in the blood. This state is called hypercalcemia. The symptoms are the following:

  • Decrease in appetite

  • Nausea and vomiting

  • Constipation

  • Dehydration

  • Increased thirst, which cannot be appeased

  • Frequent urination

  • Confusion, fatigue

  • Muscle weakness and therefore difficulty walking

  • Bone pain and kidney stones


Not saying you'll experience the whole package, but if you experience one of the symptoms above, recommended is to consult your doctor and test the vitamin D concentration in your blood.


Prevention of Vitamin D Toxicity

We've got the symptoms, we've got the causes, and we know what vitamin D toxicity is. What's left is finding out how to prevent vitamin D toxicity. In this section of the blog, we'll give you the tips you need to prevent yourself from vitamin D toxicity. Quite simple, but essential to know when you're thinking about supplementing vitamin D for example.


The first thing you should always do when you're not sure about vitamin D supplementation is to talk to your healthcare provider about vitamin D. He'll tell you whether vitamin D supplementation is a good idea, based on your personal situation. If you're experiencing some kind of medial issues, for example, vitamin D supplementation may not be your best option as there might already be enough vitamin D in the blood. Make sure to prepare your consult with the section below.


Also: never take more supplements than what your provider recommends you. For most healthy teenagers, 100mcg per day is the recommended amount. Some supplements contain 250mcg per serving, but there's no need to supplement more than your body needs. Hypercalcemia (too much calcium in the blood) is one of the most common effects of excessive amounts of vitamin D intake, resulting in weaker bones and kidney stones.


The same goes for prescription vitamin D. Never take more than your prescription vitamin D that your provider prescribes.


Our 4th tip for preventing vitamin D toxicity comes down to regular testing the levels of vitamin D in the blood. This is the only way to determine whether you should supplement vitamin D


This one might be a bit obvious, but we feel forced to make you aware of this: always keep your children and pets away from kids and pets.


Did you know, that pets also need their vitamin D? The only way they get their vitamin D is by their diet, as their skin lacks the ability to use sunlight to syntheseize the vitamin D precursor. Excessive amounts of vitamin D can cause serious health problems in pets.


Diagnosing Vitamin D Toxicity

The only way to find out if you suffer from vitamin D toxicity is by consulting your healthcare provider. He/she will diagnose whether you suffer from vitamin D toxicity based on the following factors.


Your Symptoms

  • Nature of Pain/Discomfort: Describe the specific type of pain or discomfort you are experiencing. Is it sharp, dull, or burning? Specify the exact location and whether it spreads out to other areas.

  • Duration and Frequency: Note how long you have been experiencing these symptoms and how often they occur. Are they constant, or do they come and go? Include any patterns you have noticed.

  • Aggravating and Alleviating Factors: Identify any activities, foods, or conditions that seem to trigger or worsen your symptoms. Also, mention any actions or treatments that provide relief, such as rest, medication, or specific exercises.

  • Associated Symptoms: List any other symptoms that accompany your main complaint. This could include fatigue, nausea, dizziness, headaches, or changes in vision, appetite, or bowel habits.


A History of Your Medications and Supplements

  • Current Medications: List all prescription medications you are currently taking. Include the name, dosage, and frequency of each medication.

  • Over-the-counter medications: Include any non-prescription medications you regularly use, such as pain relievers, antihistamines, or antacids. Specify the name, dosage, and frequency for each.

  • Dietary Supplements: Note all vitamins, minerals, and herbal supplements you take. Include the brand, dosage, and reason for taking each supplement.

  • Past Medications and Supplements: Provide a history of any previous medications or supplements you have taken. Mention why you were taking them and why you stopped.


Vitamin D Blood Tests

  • Recent Test Results: Provide the date and results of your most recent vitamin D blood test. Include the specific vitamin D levels measured, such as 25-hydroxyvitamin D.

  • Historical Data: Include results from any previous vitamin D tests for comparison. This helps to track changes over time and assess trends.

  • Health Implications: Discuss any symptoms or health issues that prompted the vitamin D testing. This could include bone pain, fatigue, or other signs of deficiency or insufficiency.

  • Recommendations and Treatments: Note any advice or treatment plans given by your healthcare provider based on your vitamin D levels. This might include taking vitamin D supplements, dietary changes, or increased sunlight exposure.


A Calcium Blood Test

  • Recent Test Results: Provide the date and outcome of your latest calcium blood test. Include the measured calcium level and any reference ranges for normal levels provided by the lab.

  • Reason for Testing: Explain any symptoms or health concerns that led to the calcium blood test. This might include muscle cramps, bone issues, or concerns about parathyroid function.

  • Healthcare Provider's Advice: Summarize any recommendations or treatment plans given by your healthcare provider based on your calcium test results. This might involve dietary adjustments, supplements, or further medical evaluation.

  • Comparative Data: Include results from previous calcium tests to observe any trends or significant changes over time. This helps to identify whether your calcium levels are stable, increasing, or decreasing.


Kidney Function Tests

  • Specific Tests Performed: List the specific kidney function tests conducted, such as creatinine, blood urea nitrogen (BUN), and glomerular filtration rate (GFR). Explain what each test measures.

  • Recent Test Results: Provide the date and outcomes of these tests. Note any values that fall outside the normal range and what those deviations might indicate.

  • Reason for Testing: Describe any symptoms or medical conditions that necessitated kidney function testing. This might include high blood pressure, diabetes, or frequent urinary tract infections.

  • Provider's Recommendations: Include any advice or treatment plans from your healthcare provider based on the kidney function test results. This might involve dietary changes, medications, lifestyle adjustments, or further testing.


Preparing these questions will make it easier for your doctor to find out whether you're suffering from vitamin D toxicity or not.



Conclusion

In conclusion, vitamin D is an essential nutrient that plays a crucial role in maintaining overall health, particularly in improving mood, regulating heart function, and supporting bone health. During the winter months, when sunlight exposure is limited, vitamin D supplementation becomes especially important to prevent deficiencies that can lead to symptoms like fatigue, muscle weakness, and bone pain.


However, it is vital to balance the benefits of vitamin D with the risks associated with excessive intake, which can result in vitamin D toxicity.


Vitamin D toxicity, primarily caused by over-supplementation, leads to a dangerous buildup of calcium in the blood, known as hypercalcemia. This condition can cause a variety of symptoms, including nausea, vomiting, constipation, dehydration, and more severe complications like kidney stones and bone pain. To avoid these adverse effects, it is crucial to adhere to recommended dosages and consult healthcare providers before starting any new supplement regimen. Regular monitoring of vitamin D levels through blood tests can help ensure safe supplementation practices and maintain optimal health without the risks of toxicity.


Frequently Asked Questions (FAQ)

What is Vitamin D Toxicity?

What causes Vitamin D Toxicity?

What are the symptoms of Vitamin D Toxicity?

How can Vitamin D Toxicity be prevented?

How is Vitamin D Toxicity diagnosed?

What are the health implications of Vitamin D Toxicity?

Where can I find more information on Vitamin D Toxicity?



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