Introduction
When vitamin D levels are low and not enough may be obtained by diet or sun exposure, vitamin D pills are sometimes used. High-dose vitamin D supplements, if taken regularly for an extended period, may occasionally induce unwanted side effects.
What Is Vitamin D?
Vitamin D is crucial for bone health because it facilitates calcium absorption. Your muscles, nervous system, and immune system will all benefit from it as well. There is evidence linking this vitamin's absence to mood disorders like depression and SAD (SAD). Black and Hispanic individuals, who make up around 40% of the adult populatioan, are at the greatest risk of vitamin D insufficiency. Vitamin D deficiency is common, and many might benefit from getting more sun, making dietary adjustments, or taking a supplement if their doctor recommends it.
While vitamin D insufficiency is extremely frequent, vitamin D excess is extremely unusual. Vitamin D toxicity, also known as hypervitaminosis D, occurs when the body has an excessive amount of the vitamin. Because of the risk of eating an excessively high amount, you must discuss taking supplements with your doctor before beginning treatment.
Vitamin D is currently advised at 600 IU every day for persons under the age of 70, and 800 IU for those over 70. Common wisdom suggests that up to 4,000 IU daily is safe, but studies have shown that even doses of 10,000 IU/day are not hazardous. Many incidents of vitamin D poisoning have been traced back to mistakes in dosing, which resulted in substantially larger levels being consumed than were intended.
Consuming excessive amounts of vitamin D is often difficult.
Toxic Levels Of Vitamin D — Define. When Taking Supplements, Should I Be Concerned?
Hypervitaminosis D, or vitamin D poisoning, is an uncommon but potentially fatal illness caused by an overabundance of vitamin D in the body. Supplements, not food or sunlight, are typically the source of vitamin D intoxication. This is because your body controls how much vitamin D you make in response to sunlight, and that even fortified meals don't contain excessive levels of the nutrient.
Hypercalcemia, or an excess of calcium in the blood, is the most common symptom of vitamin D toxicity. Other symptoms include vomiting, weakness, and increased urination. Calcium stones in the kidneys and aching bones are two potential outcomes of vitamin D intoxication.
Treatment consists of cessation of vitamin D use and a reduction in calcium consumption. Medications and fluids given intravenously, such as corticosteroids and bisphosphonates, may also be prescribed by your doctor. Studies have indicated that excessive vitamin D intake (above 60,000 IU daily) can be hazardous over many months. This is significantly greater than the daily RDA of 600 IU for individuals in the United States.
Some medical conditions, such as vitamin D deficiency, require the administration of doses higher than the RDA, however, this is always done under the supervision of a doctor and only for a limited amount of time. To ensure the safe use of high vitamin D doses, blood levels must be tested regularly.
Before beginning any supplement regimen, it is recommended that you consult with your doctor.
10 Side Effects of Too Much Vitamin D
Elevated Blood Levels
Vitamin D levels in the body must be greater than 100 ng per mL before they become toxic or harmful. Blood vitamin D levels above 100 ng/mL are considered to be hypervitaminosis D, whereas serum values above 150 ng/mL are considered to be vitamin D intoxication.
Vitamin D levels between 30 and 60 ng/mL have been suggested as ideal and may offer protection against disease and illness, despite conflicting recommendations. A healthy person's blood vitamin D levels are quite unlikely to ever approach excessive or dangerous levels, even when taking large doses of vitamin D supplements.
Incorrect supplement dose and prescription errors account for the vast majority of incidents of vitamin D poisoning. As one example, a 73-year-old man was reported to have vitamin D toxicity in 2020 due to his long-term use of 10,000 international units (IU) of vitamin D per day. An additional case report from 2020 describes a 56-year-old woman who took 130,000 IU of vitamin D daily for 20 months to treat her multiple sclerosis but ended up in the hospital due to side effects like nausea, vomiting, and muscle weakness. Her blood test results showed that she had 265 ng/mL of vitamin D. Keep in mind that 130,000 IU is more than 30 times the daily maximum of 4,000 IU that is considered safe.
Experts recommend that adults with ordinary vitamin D levels do not exceed 4,000 IU of vitamin D per day. Toxicity is unlikely as long as daily intake levels are below 10,000 IU and extremely high intakes of vitamin D supplements are avoided. Keep in mind that the current UL for vitamin D is 4,000 IU per day, but that persons who are deficient in vitamin D often need to take much higher doses than that. In any case, before beginning any new medication, it's always smart to talk to a doctor about the appropriate dosage. By doing so, you can reduce the risk of administering an incorrect or harmful dose.
Conclusion - Levels of vitamin D3 above 100 ng/mL may be hazardous. People who took vitamin D supplements at megadoses (very high dosages) for a long time showed signs of toxicity at very high blood levels.
Kidney Problems
Excess vitamin D can produce hypercalcemia, which in turn can harm the kidneys. Having an excess of vitamin D might cause kidney stones because it boosts calcium absorption. Evidence also suggests, however, that more severe, long-term damage to the kidneys is possible. Nephrocalcinosis, caused by calcium deposits, can cause long-term kidney damage or even kidney failure.
Vitamin D3 doses higher than 3,600,000 IU were associated with an increased risk of kidney injury, according to the results of a recent scientific study. Keep in mind that these amounts are many times more than what you'd get from a moderate amount of sun exposure or a typical multivitamin.
Brittle Bones And Bone Pain
Hypercalcemia, and the bone issues that follow, such as decreased bone density, can be brought on by excessive vitamin D intake.
Some of the symptoms are:
- bones that are aching or hurting badly
- bones with a high risk of breaking
- cysts of bone
- walking abnormalities
Blood Calcium Levels That Are Too High
Supplementing with vitamin D improves calcium absorption from the diet. This is arguably the most crucial function of the system. However, if you take in too much vitamin D, your blood calcium levels could rise to dangerously high levels, which can be uncomfortable at best. Vitamin D poisoning manifests predominantly through hypercalcemia or abnormally high blood calcium levels.
Some of the signs of hypercalcemia are:
- issues with digestion, such as tummy aches, burping, vomiting, and nausea
- exhaustion, lightheadedness, hallucinations, and brain fog
- lack of hunger
- problem with urinating a lot
- stones in the kidneys, renal damage, and kidney failure
- elevated heart rate and blood pressure
- dehydration
Blood calcium levels should be between 8.5 and 10.8 mg/dL. When vitamin D is used in large dosages for an extended period, hypercalcemia often develops. For instance, one case study from 2015 described how a man with dementia who took 50,000 IU of vitamin D daily for 6 months ended up in the hospital multiple times due to elevated calcium levels. Similarly, a woman who took 130,000 IU of vitamin D daily for 20 months was hospitalized in 2020 for hypercalcemia-related symptoms.
A few examples are feeling sick, throwing up, having weak muscles, and kidney damage. Calcification in her blood was 3.23 mmol/L (12.9 mg/dL). In severe cases, hypercalcemia can be fatal and necessitates prompt medical intervention. One's health may be in jeopardy if one takes in too much calcium from an overdose of vitamin D, which can occur due to taking in too much vitamin D.
Dehydration
The kidneys' ability to concentrate urine is impaired by high blood calcium levels. This can cause polyuria, which is the production and passage of excessive amounts of urine. Large amounts of fluid and electrolytes are lost in dilute urine. Dehydration is a potential risk for someone with vitamin D toxicity.
Some signs of mild dehydration are:
- symptoms such as dehydration (dry mouth, tongue, increased thirst, dark urine, headache, and fatigue)
- Dehydration can be fatal if it progresses too far. In addition to these classic symptoms, this illness can also cause:
- irregular breathing and racing heart
- headaches from not peeing
- blood pressure that is too low
- persistent, unexplained fatigue
Gastrointestinal Symptoms
The primary negative effect of high vitamin D levels is elevated blood calcium levels. The following are some of the most prominent signs of hypercalcemia:
- nausea
- vomiting sconstipation
- loss of appetite diarrhea
On the other hand, not everyone with hypercalcemia has the same symptoms. Taking a supplement that turned out to have 78 times as much vitamin D as it said on the label caused nausea and weight loss for one woman. Calcium levels of 12 mg/dL were observed after very high dosages of vitamin D3, which triggered severe symptoms.
One case study had a young kid who experienced stomach pain and constipation after taking mislabeled vitamin D tablets. His brother, on the other hand, experienced higher blood levels but no additional symptoms. A case study with a 3-month course of 50,000 IU of vitamin D3 led to gastrointestinal distress and other symptoms in an 18-month-old infant. When the child stopped taking the vitamins, the symptoms went away.
Summary - Vitamin D supplements may raise blood calcium levels, which can have undesirable effects. Increased calcium levels might cause stomach discomfort, loss of appetite, constipation, or diarrhea in those who take high doses of vitamin D.
Pancreatitis
Acute pancreatitis, often known as inflammation of the pancreas, can be brought on by hypercalcemia. According to a review conducted in 2017, 2 of 19 patients with vitamin D toxicity had severe pancreatitis. Over three to four months, each had consumed roughly six million IU of the vitamin.
Pancreatitis symptoms include:
- Intense, radiating pain in the upper abdomen
- nausea
- vomiting
- fast heart rate
- Painful, hot belly
- High temperature
Altered Mental Status
Individuals with vitamin D poisoning may experience mental state changes due to hypercalcemia. Hypercalcemia is a typical indication of vitamin D toxicity, and it often manifests in mental health issues like confusion, sadness, and psychosis. Coma has been observed in severe cases.
A 64-year-old man consumed 200,000 IU of vitamin D daily after misinterpreting the dosage guidelines, according to a case report from 2021. He was exhibiting severe symptoms of hypercalcemia, including changes in mental status. After the first 10 days of his hospital stay, his agitation and confusion subsided as his calcium levels normalized. Calcium levels in his body returned to normal after around 18 days.
Summary - Confusion, agitation, and unresponsiveness are all indications of vitamin D intoxication. This is likely due to the increased calcium levels brought on by excessive vitamin D.
Hypercalcemia
Hypercalcemia, or high blood calcium levels, can result from taking excessive amounts of vitamin D. The following are some symptoms of hypercalcemia:
- Loss of Appetite
- Constipation
- Depression
- Headaches
- Confusing memories
- Thirst Tiredness
Two standard deviations over the mean in serum calcium levels in the blood are considered hypercalcemia. Calories in the blood should be between 8.8 and 10.8 milligrams per deciliter. Serum calcium levels between 10.5 to 13.9 mg/dL are considered mild to moderate, while calcium values from 14.0 to 16.0 mg/dL are considered a hypercalcemia crisis. Steroids are effective in treating hypercalcemia induced by an excess vitamin D, but it is also important to find and remove the source of the excess vitamin D.
Deficiency and Toxicity
Vitamin D helps the body absorb calcium, boosts the immune system, and safeguards the health of bones, muscles, and the heart. It can be found in a variety of foods and is also produced by your body in response to sun exposure. However, vitamin D-rich meals are hard to come by, with the notable exception of fatty fish. And most individuals don't receive enough sun to make enough vitamin D.
Accordingly, deficiencies are extremely common. It's estimated that almost 1 billion people throughout the world don't get enough vitamin D, and another 50% may not be getting enough to stay healthy. Your vitamin D levels can only be determined by a doctor's examination.
Serum vitamin D values below 20 ng/mL are considered deficient in vitamin D and are widely accepted as the threshold for diagnosing vitamin D deficiency. It is generally agreed that people whose vitamin D levels are between 21 and 29 ng/mL are deficient. If your doctor determines that your vitamin D levels are too low, he or she may prescribe a supplement or suggest that you get injections of vitamin D.
When vitamin D levels are extremely low, doctors may prescribe extremely high weekly doses of 50,000 IU for 8 weeks, then a maintenance dose of 2,000 IU per day. Depending on your current vitamin D levels and overall health, your doctor will determine the optimal vitamin D dosage for you. Misusing vitamin D pills, whether they be over-the-counter or prescribed, or injections, can put you at risk for vitamin D toxicity.
Your vitamin D levels will be monitored by your doctor if you are taking high-dose vitamin D pills or getting vitamin D injections. If your doctor hasn't prescribed high-dose vitamin D pills, don't take them.
Conclusion - Vitamin D insufficiency is very widespread. This is why lots of folks need to load up on vitamin D3 pills. You shouldn't use vitamin D pills in large doses unless your doctor tells you to.
Depression and Vitamin D Deficiency
For the vast majority of the population, vitamin D deficiency is the bigger issue. Bone health is only one aspect of the body that might suffer from a lack of this nutrient; impaired brain function and development are also possible outcomes. Studies have linked schizophrenia, bipolar disorder, and other mental illnesses to insufficient vitamin D levels. Depression and SAD are also linked to low vitamin D levels.
But that doesn't mean that increasing your vitamin D levels will automatically make your depression go away. Depressive disorders cannot be effectively treated with vitamin D supplementation, according to the results of a single randomized controlled experiment.
If you're feeling down, whether or not it's seasonal, it's best to consult a doctor before turning to a supplement like a vitamin D. It is up to your doctor to determine if vitamin D could be helpful or if another treatment option would be better given your specific condition.
Symptoms of Too Much Vitamin D
Too much vitamin D: what could go wrong? Getting too much vitamin D can manifest in a variety of ways.
- Loss of Appetite
- Constipation
- Dehydration
- Disorientation
- Dizziness
- Fatigue
- Urinating often
- Excessive BP
- Irritability
- Weakness of the Muscles
- Nausea
- Thirst
- Tinnitus
- Vomiting
You should consult a medical professional if you are experiencing any of these signs. Tell them exactly what you take, including any herbs, vitamins, or other supplements, and how much of each you take. Your doctor may order blood serum level tests if they suspect vitamin D toxicity is to blame for your symptoms.
In What Amounts Of Vitamin D Do You Need It?
Below is a table displaying the RDA for various age groups. The National Academies of Sciences, Engineering, and Medicine have issued these suggestions. Your healthcare practitioner may recommend a different dose for you based on several circumstances, so it's important to always get their input before making any changes to your treatment plan. For clarity, "IU/day" means "International Units per day," as this is how vitamin D content in food and vitamin D supplements is typically expressed.
Daily vitamin D RDA and maximum safe intake level:
- To the Age of Six Months and Under - At 400 IU per day, intake is considered sufficient, Tolerable Upper Intake Level: 1,000 IU/day for Babies Ages 6-12 Months
- Children ages 1-3 have a daily maximum intake of 1,500 IU, Recommended daily intake is 600 IU, Consumption should not exceed 2,500 IU daily.
- Young ones aged 4-7 - A daily intake of 600 IU is suggested, Daily maximum dosage of 3,000 IU
- Individuals aged 9 to 70 - Recommended daily intake is 600 IU, Daily maximum dosage of 4,000 IU
- Aged individuals above 70 - Upper intake level of 4,000 IU/day
- Women 14-50 years old who are pregnant or nursing Recommended dietary allowance of 800 IU/day, Recommended daily intake is 600 IU, Daily intake maximum of 4,000 IU
These amounts serve as a reasonable starting point for treating vitamin D deficiency, although doctors may prescribe more if necessary. Naturally, you should consult your doctor to find out the optimal vitamin D dosage for you.
How Can You Figure Out How Many Ius Of Vitamin D You Need?
The amount of vitamin D in a supplement is often given in either International Units or micrograms (2.5 micrograms = 100 IU) on the nutritional label. The unit of measure "microgram" can be abbreviated "mcg." The labels of some foods may not clearly state the vitamin D content. The Daily Value (DV) is a percentage of 800 IU that is sometimes included on food labels to show how much vitamin D a single serving of a food product contains.
How Much Vitamin D Is Too Much?
Vitamin D toxicity is poorly understood, making it difficult to establish a hard and fast limit for safe or deadly vitamin D intake. The National Academy of Medicine (previously the Institute of Medicine) has established 4,000 IU as the maximum acceptable daily consumption of vitamin D. However, toxicity has not been observed in healthy individuals at dosages up to 10,000 IU.
Vitamin D toxicity is most commonly caused by taking too much of the supplement, rather than from food or sun exposure. Recent increases in supplement use may increase in reported cases of vitamin D poisoning, even though this illness is extremely uncommon.
The hazardous dose for humans is between 40,000 and 100,000 international units (1,000 and 2,500 mcg) per day, taken throughout 1 to several months. On a cumulative basis, this exceeds the safe upper limit by a factor of 10–25 times. Vitamin D toxicity typically manifests in those with blood levels over 150 ng/mL (375 nmol/L). Several incidents have also been traced to manufacturing mistakes; in these situations, the vitamin D pills in question included 100-4,000 times the amount of vitamin D that was advertised.
Toxic blood levels were between 644 and 1549 nmol/L (257 and 620 ng/mL). In most situations, vitamin D toxicity may be treated, but in extreme cases, kidney failure and arterial calcification can occur.
Conclusion - Four thousand international units per day are the maximum that can be safely consumed. Humans have shown signs of toxicity at doses between 40,000 and 100,000 IU per day, which is 10-25 times the safe upper limit.
Does Vitamin D Tolerance Fluctuate With The Consumption Of Other Fat-soluble Vitamins?
Vitamin K and vitamin A, two other fat-soluble vitamins, are suspected of having significant effects on vitamin D toxicity. High levels of vitamin D may deplete vitamin K reserves in the body, which could disrupt calcium homeostasis. Increasing one's vitamin A consumption may help prevent this by allowing one's vitamin K reserves to last longer.
Magnesium is an additional possible-but-probably-important nutrient. It's a key component in maintaining strong bones. Therefore, supplementing with vitamin A, vitamin K, and magnesium in addition to vitamin D may enhance bone health and decrease the likelihood of other tissues being calcified. These are only speculations, but if you're going to take a vitamin D supplement, it could be smart to make sure you're also receiving enough of these minerals.
Summary
Making sure you're getting enough of other nutrients like vitamins A and K and magnesium is also crucial if you're taking a vitamin D pill. These might mitigate the potential side effects of a vitamin D boost.
Vitamin D is a hormone, and its effects at high concentrations vary widely across individuals. As a result, it's difficult to determine what doses are safe and what aren't. Adverse health effects from vitamin D poisoning may take months or even years to manifest after beginning high-dose treatment. As a rule, 4,000 IU (100 mcg) per day is considered the maximum safe intake.
No evidence taking a higher dose will improve your health, therefore you may not need to. Although a high amount of vitamin D may be used on occasion to correct a deficiency, it is important to have medical or nutritional advice before taking such a significant quantity on your own. More is not necessarily better when it comes to nutrition, as is the case with many other things.
Conclusion
While vitamin D supplements can have positive effects on both physical and mental health, their usage should be approached with prudence. Talk to your doctor before beginning any supplementation with vitamin D.
Studies have linked high vitamin D intake to an increased risk of kidney stones and bone fractures. High doses of supplements have also been associated with an increased risk of developing cancers of the prostate and pancreas, as well as an overall higher risk of death.
