Does vitamin D cause constipation?

Medically reviewed on August 1, 2022 by Jordan Stachel, M.S., RDN, CPT. To give you technically accurate, evidence-based information, content published on the Everlywell blog is reviewed by credentialed professionals with expertise in medical and bioscience fields.

Table of contents

• How can vitamin D affect bowel movements?
• Are there other vitamins that might contribute to constipation?
• What other side effects might come with vitamin D?
• Get in tune with your vitamin D levels with Everlywell

Ensuring that you get enough vitamin D in your daily diet can help support immune health, cellular growth, and bone development. [1] While some opt for fortified foods like milk and cereals for their daily dose of vitamin D, others opt to take supplements.

Can you take too much vitamin D? Yes, you can and it can potentially harm your gastrointestinal tract, which may lead to nausea, diarrhea, vomiting, or constipation.

How can vitamin D affect bowel movements?

So, does vitamin D cause constipation? Not exactly, but constipation is often a side effect of too much vitamin D. You might be wondering “How much vitamin D should I take?” It is generally recommended to have 400 to 800 IU daily. To help you understand how vitamin D intake is related to your bowel movements, let’s break down some facts about vitamin D and your body: [1]

• Vitamin D is fat soluble – Vitamin D is a fat soluble vitamin. This means it’s absorbed with dietary fats. From there, vitamin D is stored in your liver and other fatty tissues. A fat soluble vitamin is excreted like water-soluble vitamins. Therefore, if you get too much of a fat soluble vitamin it’s stored in your body.
• Hypercalcemia – Is vitamin D good for bones? When you consume the right amount, vitamin D does its job—helping your body with calcium absorption for strong bones. When you get too much calcium intake, it builds up in your bloodstream. This is known as hypercalcemia.
• Digestive problems – Hypercalcemia can lead to a host of digestive problems. You might experience nausea, vomiting, and diarrhea. Others experience the opposite end of the spectrum—constipation. If left untreated, more serious problems can occur, including renal failure and even death.

Can the right amount of vitamin D keep your digestive system on track?

While you don’t want to go overboard on vitamin D supplementation, the right amount can help keep your digestive system humming along optimally. [2] In fact, a study of 86 patients who suffered from chronic constipation found that vitamin D deficiency was one of the key contributors to their digestive troubles.

The World Journal of Gastroenterology proposed that potential links between vitamin D and chronic constipation could be tied to the increase in inflammation and poor immune response that may accompany vitamin D deficiency.

Are there other vitamins that might contribute to constipation?

A toxic amount of vitamin D might not cause your constipation. There are other vitamins that can contribute to gastrointestinal problems as well. These may include: [3]

• Calcium – While some people can take calcium supplements without any problems, others find they experience an increase in gastrointestinal problems, including constipation, bloating, gas, and stomach cramps when taking calcium. If you’re taking both calcium and vitamin D supplement, the combination of these two might cause you some stomach distress.
• Iron – Iron supplements are also known to cause gastrointestinal problems. Iron can be difficult to digest when taken in supplement form and constipation is a common symptom associated with excess iron. Your healthcare provider may recommend a stool softener to relieve the discomfort caused by an iron supplement.

Constipation may also derive from causes outside of diet and supplement intake, such as:

• Dehydration
• Certain medications
• Insufficient dietary fiber intake
• Stress
• Lack of exercise
• Genetic predisposition
• Colon problems

You should always consult with your healthcare provider if you’re experiencing constipation. They can rule out more serious issues and help you mitigate gastrointestinal discomfort.

What other side effects might come with vitamin D?

Constipation isn’t the only side effect associated with toxic vitamin D intake. In addition to gastrointestinal distress, excessive vitamin D intake may also lead to:

• Loss of appetite
• Excessive thirst and dehydration
• Frequent urination
• Muscle weakness
• Pain
• Confusion
• Kidney failure
• Irregular heartbeat
• Death

On the other hand, too little vitamin D can also lead to: [4]

• Bone deformities in children
• Bone aches
• Muscle weakness

Get in tune with your vitamin D levels with Everlywell

Your body requires a delicate balance of vitamins to function optimally. Too much or too little of necessary nutrients, such as vitamin D, can cause significant health problems.

That being said, when you intake excess or toxic levels of vitamin D, you may experience constipation, in addition to other digestive problems, loss of appetite, and muscle weakness.

If you’re uncertain if your vitamin D levels are where they should be, Everlywell can help. Our at-home Vitamin D Test is an easy and convenient way to check your vitamin D from the comfort of your home. Also note that you can now purchase vitamin D supplements directly from Everlywell. If you're experiencing various bowel-related symptoms, consider taking an at-home colon cancer test.

Related content

Is vitamin D good for bones?

Can you take too much vitamin D?

How much vitamin D should I take?

References

1. VItamin D Fact Sheet. National Institutes of Health. URL. Accessed August 1, 2022.
2. Chronic Functional Constipation is Strongly Linked to Vitamin D Deficiency. World Journal of Gastroenterology. URL. Accessed August 1, 2022.
3. Chronic Constipation. Medicine. URL. Accessed August 1, 2022.
4. Vitamin D. National Institutes of Health. URL. Accessed August 1, 2022.