Are Vitamin D Supplements Safe? (Answered!)

Are Vitamin D Supplements Safe? (Answered!)

Vitamin D supplements are considered safe, and toxicity is rare. This is because to reach toxic or harmful levels in the body, a healthy person would need to consume exceptionally high amounts of vitamin D over time.

You probably heard the advice to "eat your greens" at least once as a child since they would help you grow strong bones, hair, teeth, and muscles and make your hair curl. However, we are unlikely to get enough vitamin D no matter how healthy our diet is (especially in winter).

For many, a common go-to remedy is to take vitamin D supplements.

After all, the supplements have been hailed as nearly a miracle. But are they safe? 

In this post, we'll examine who needs to take vitamin D supplements, whether it's safe to do so, how much vitamin D is recommended, and whether it has any side effects.

What are vitamin D supplements?

Vitamin D supplements are products that people take to increase their vitamin D intake. These supplements are taken by people to ensure they obtain enough vitamin D and to enhance their health. 

Vitamin D is a fat-soluble nutrient that aids the body's calcium and phosphorus absorption. It is, therefore, essential for the health of the bones and muscles.

Whenever the body is exposed to sunlight, it produces active vitamin D. It is a hormone that helps cells and organs operate. It is also produced from a relatively limited number of foods.

It also serves several other purposes in addition to those related to bone and muscle health. It controls vascular disease, strengthens the immune system, lowers cancer mortality, lowers inflammation, lifts mood, and reduces the risk of depression.

Who needs to take vitamin D supplements?

Some pre-existing illnesses necessitate a higher vitamin D consumption for certain people. To meet their body's needs, these individuals need vitamin D supplements.

These groups include:

People who receive limited sun exposure

People who receive limited sun exposure

The optimum time to get vitamin D is from 10 am to 3 pm when the sun is most potent. Therefore, you can benefit from taking vitamin D supplements if you frequently work remotely or have a 9 to 5 job.

The northern hemisphere, including New York, receives very little sunlight from April to October. Vitamin D deficiency may result from this. Furthermore, Vitamin D enhances mood, so living in an area with a lot of gray is also one reason people are susceptible to seasonal depression.

Additionally, if you cover your entire body or wear dark clothing because of personal preference, cultural or religious observance, or both, you may be deficient in vitamin D.

People who have undergone weight loss surgery

If you've undergone weight-loss surgery, your stomach will be smaller. The same is true for those who have undergone gastric bypass surgery. Your stomach may have trouble absorbing vitamin D.

Your doctor will often monitor your vitamin D metabolism for a time to ensure it's in check. If it isn't, however, they can put you on vitamin D supplements.

Infants and young kids

The Department of Health and Social Care advises that infants from birth to one year old take a daily supplement with 8.5 to 10 micrograms of vitamin D if they are breastfed or formula-fed.

Throughout the year, children aged 1 to 4 should receive a daily supplement containing ten micrograms of vitamin D.

People with bone diseases

People with bone diseases

If you have certain bone illnesses, such as osteoporosis and Paget's disease, you'll need substantial dosages of vitamin D.

These brittle bone disorders are discovered through bone mineral density examinations. Usually, medical professionals recommend vitamin D-enriched meals and calcium and vitamin D supplements.

People who have liver and kidney illnesses

People who have liver and kidney illnesses

Using certain enzymes, the body typically transforms vitamin D into a usable form. But the amount of this enzyme in a person's body tends to be lower among those with liver or kidney illness. They require vitamin D in a more ready form for this reason.

The kidney and the liver secrete the hepatic enzyme 25-hydroxylase and 1-alpha-hydroxylase, which both break down vitamin D. You will want a vitamin D supplement to compensate for the lack of these enzymes.

Is it safe to take vitamin D supplements?

Vitamin D supplements are safe, and toxicity is uncommon. This is because a healthy person would need to ingest high amounts of vitamin D over time for it to accumulate to hazardous or damaging levels in the body.

However, it is essential to maintain healthy levels of vitamin D to prevent toxicity. 

How much vitamin D should you take?

The average person in the United States needs 600 IU of vitamin D daily, while persons over 70 years need 800 IU. For persons nine years and older, 4,000 IU is the safe daily consumption level (100 mcg).

However, a vitamin D overdose is possible. A middle-aged man consumed a vitamin cocktail that included 150,000 IU of vitamin D and more omega-3, folate, and vitamin B3 than is advised.

He visited the hospital after exhibiting symptoms such as vomiting, leg cramps, diarrhea, weight loss, thirst, and others.

Vitamin D intoxication seldom affects an average person. It requires ingesting extremely high doses repeatedly over an extended time.

Are there any negative effects of Vitamin D?

It can be dangerous to take excessive amounts of vitamin D in the form of supplements. When taking more than 4,000 IU of vitamin D each day, children and adults over the age of nine, pregnant women, and nursing mothers may have the following negative effects:

Elevated blood levels

Vitamin D levels in the body must be greater than 100 nanograms (ng) per mL to become toxic or harmful.

Blood vitamin D concentrations exceeding 100 ng/mL are considered hypervitaminosis D, whereas serum concentrations over 150 ng/mL are considered vitamin D intoxication.

Although recommendations for optimal vitamin D levels vary, evidence points to values between 30 and 60 ng/mL as likely ideal and protective of health.

A healthy person's blood vitamin D levels are unlikely even to approach excessive or dangerous levels, even when taking large doses of vitamin D supplements.

Most vitamin D toxicity occurrences are caused by incorrect supplement dosage and written prescription errors.

Increased blood calcium levels

Your body can easily absorb calcium from the diet if you have vitamin D. In actuality, this is one of its most significant functions. However, if you consume too much vitamin D, your blood calcium levels could rise to the point where they induce uncomfortable and sometimes harmful symptoms.

Blood calcium levels should be between 8.5 and 10.8 mg/dL. 

The leading cause of the symptoms of vitamin D toxicity is hypercalcemia or abnormally high blood calcium levels.

Acute medical care is necessary because hypercalcemia poses a risk to life.

Kidney problems

Vitamin D toxicity can cause kidney damage or even failure in some cases.

A lot of vitamin D in the body can produce high calcium levels, promoting water loss through excessive urination and kidney calcification.

Additionally, hypercalcemia can cause kidney vessels to narrow, which impairs kidney function.

In fact, many studies have shown that people who experience vitamin D intoxication may experience mild to severe kidney damage.

It's important to note that people with kidney disease who are vitamin D deficient can experience serious difficulties and damage to their kidneys. For this reason, it's important to keep vitamin D levels in the blood at their ideal levels.

Altered mental state

Hypercalcemia can result in an altered mental state when a person has vitamin D toxicity.

Confusion, despair, and psychosis are common vitamin D toxicity-induced hypercalcemia symptoms. There have been reports of coma in severe cases.

A 64-year-old man mistakenly consumed 200,000 IU of vitamin D daily in a 2021 case report because he misread the directions for his medicine. He displayed a changed mental state as well as other severe hypercalcemia-related symptoms.

For the first ten days of his stay in the hospital, he remained anxious and confused, but as his calcium levels fell, his symptoms gradually got better. However, he had to wait around 18 days for his calcium levels to stabilize.

What should you not take with vitamin D supplements?

When using this combination, exercise caution:


Persons with kidney failure who take vitamin D and phosphate binders that include aluminum, sometimes used to treat excessive serum phosphate levels in people with chronic kidney disease, may eventually develop dangerously high amounts of aluminum.


Phenobarbital and phenytoin (Dilantin, Phenytek), two anticonvulsants, cause an increase in vitamin D breakdown and decrease calcium absorption.


The processing of this cholesterol medication by your body may be hindered by vitamin D supplement intake.


You shouldn’t take Psoriasis medication with vitamin D. The mixture could make it more likely that there will be too much calcium in the blood (hypercalcemia).


Prednisone and other steroid medications may decrease calcium absorption and interfere with the body's utilization of vitamin D.

Stimulating laxatives

High doses of stimulant laxatives taken over an extended time can decrease calcium and vitamin D absorption.


High vitamin D intake while taking this blood pressure medication can result in hypercalcemia and may lessen verapamil's effectiveness.

Takeaway: Taking vitamin D in the recommended dosage is safe, and it will improve your quality of life

Most people don't experience any negative side effects if vitamin D is used in moderation. Vitamin D supplementation is highly effective. You can use them to get your body's recommended amount of vitamin D daily.

Contact us at Why Not Natural to get the best supplements for optimal health. We provide premium natural vitamin D3 supplements. Our products follow the ideal guidelines for dietary supplements: Available in liquid form and 100% natural.

Our Vitamin D3-K2 capsules contain 110,000 IU of D3 per capsule, making them ideal for people who need to raise their vitamin D concentration level quickly. Additionally, they are filler-free and feature US-grown Spirulina!

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