Vitamin D is vital for many processes in the human body, such as building and maintaining our bone structure. But what happens if you take excess vitamin D3? And how much vitamin D are you supposed to take everyday? Is taking 1000 IU of vitamin D3 safe?

Learn more about vitamin D overdoses in the article below.

Can taking too much vitamin D3 hurt you?

Yes. Although uncommon, vitamin D hypervitaminosis or toxicity can be a potentially serious complication of taking too much vitamin D. According to the Mayo Clinic, vitamin D toxicity is typically the result of taking large doses of vitamin D supplements, and it’s not caused by diet or excessive sun exposure.

Your body is capable of regulating the amount of vitamin D it produces in response to sun exposure to maintain healthy levels. And although fortified foods can supplement your vitamin D intake, they don’t typically contain enough vitamin to cause toxicity.

Side effects of taking too much vitamin D are uncommon, but you should still be careful and only take the recommended dose of vitamin D each day.

Can I be allergic to vitamin D?

Human beings can be allergic to pretty much anything — and yes, that includes vitamin D supplements. Most people don’t suffer from vitamin D allergies, but it’s still important to be on the lookout for signs of an allergic reaction after taking any new supplement or medication. Alternatively, you could be allergic to other components or excipients used in a supplement.

Symptoms of an allergic reaction include:

Sneezing
Runny nose
Watery, itchy, red eyes
Skin rash
Itchy throat
Swollen lips, eyes, or tongue
Shortness of breath
Coughing
Difficulty breathing

You should always seek medical attention if you develop signs of an allergic reaction to vitamin D or any other substance. Many allergic reactions are mild, but they can quickly become severe and need to be monitored and treated by a healthcare professional. You should also discontinue the substance that caused the allergy, and avoid taking it again.

Vitamin D supplements can also interact with other medications you’re taking. Keep in mind that even natural substances — such as vitamins and herbal remedies — can cause harmful interactions, so you should always ask your doctor for advice before starting a new medication or supplement.

How much vitamin D do I need per day?

In reality, the daily requirements of vitamin D for the average adult are much lower than the dosage needed to cause toxicity. According to the Mayo Clinic, the recommended dietary allowance (RDA) of vitamin D for different age groups is 600 international units (IU) per day for younger adults, and 800 IU per day for adults over the age of 70.

However, dosages such as 1,000 to 2,000 IU per day are considered to be safe. People who suffer from certain diseases may be prescribed high dose vitamin D to manage their symptoms, but these doses should be taken under medical supervision.

Vitamin D doses higher than 10,000 IU a day have been linked with toxicity. This means that you would have to take much more than a single daily supplement tablet in order to develop a vitamin D overdose. Taking high doses of vitamin supplements could also lead to gastrointestinal symptoms.

How do you know if you have a vitamin D overdose?

Taking an overdose of vitamin D is rare, but it can lead to serious and potentially life-threatening symptoms. The main consequence of elevated vitamin D is that it can increase the calcium levels in your blood (hypercalcemia), leading to a wide range of symptoms.

According to the MSD Manuals, the symptoms of vitamin D3 overdose can include:

Loss of appetite
Nausea
Vomiting
Increased thirst
Frequent urination
Weakness
Nervousness
Itchy skin

If left untreated, hypercalcemia caused by elevated vitamin D can lead to severe complications, including renal failure.

If you have a history of excessive vitamin D intake and exhibit any of these symptoms, it’s very important to seek medical assistance immediately. Depending on your condition, your doctor could order different tests and prescribe treatment. Patients with hypercalcemia may have to stay in the hospital for observation at first. Some of the medications that can interact with vitamin D include:

Anticonvulsants or seizure medications
Statins or medications for high cholesterol
Some blood pressure treatments
Steroids
Laxatives

Foods naturally high in vitamin D

Vitamin D isn’t naturally found in most foods. Instead, your body makes vitamin D when you’re exposed to direct sunlight. Additionally, many foods are fortified with vitamin D and other vitamins and minerals. According to the Harvard T.H. Chan School of Public Health, foods that contain vitamin D include:

Cod liver oil
Tuna fish
Salmon
Sardines
Beef liver
Egg yolks
Fortified cereals

What fruits have vitamin D?

As mentioned above, most foods don’t contain high levels of vitamin D. You can find orange juice that has been fortified with vitamin D, or other fortified beverages such as milk, yogurt, and plant-based milks. However, the best way to get your daily vitamin D is by getting 10-30 minutes of midday sun exposure several times each week.

FAQ: Vitamin D

Can vitamin D cause bloating?

Yes. Bloating can be a sign of excess vitamin D3 intake.

Can vitamin D cause gas?

Yes. Gas, along with other gastrointestinal symptoms, can be a side effect of too much vitamin D.

Can vitamin D cause heartburn?

Yes. Vitamin D and other vitamin supplements can cause heartburn in some people.

Can vitamin D cause sore throat?

A sore throat isn’t a common sign of vitamin D overdose.

Can vitamin D cause spotting?

No. Vitamin D hasn’t been linked to spotting or vaginal bleeding. You should consider taking an STD test if you’re experiencing signs such as spotting, genital discharge, or a foul genital odor. You can learn more about at-home STD tests at STDWatch.com.