Opened glass bottle with different types of vitamins against a yellow background

What vitamins should not be taken together?

Medically reviewed on September 27, 2022 by Jillian Foglesong Stabile, MD, FAAFP. 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

Like ketchup and ice cream, some vitamins simply don’t go together. However, unlike culinary mishaps, taking the wrong vitamins together can lead to more than just a bad taste in your mouth. In some cases, the wrong vitamin combination can negatively impact your health.

Fortunately, we’re here to give you the lowdown on what vitamins should not be taken together. That way, you can take all your vitamins safely.

Vitamins that contain copper and zinc

Although copper and zinc aren’t technically vitamins, many supplements may contain them. As a result, it can be easy to take both simultaneously—especially if you’re taking multiple supplements.

The problem is that both minerals can counteract each other. To understand why this counteraction occurs, let’s take a closer look at both minerals.


Copper is an essential mineral that helps support the body in the following ways [1]:

  • Energy production
  • Regulation of gene expression
  • Iron absorption and metabolism
  • Connective tissue formation

While the body doesn’t produce copper naturally, some foods contain copper. Many people also take copper supplements to provide the body’s daily copper requirements.


Found in the body’s cells, zinc helps the body [2]:

  • Fight off bacteria and viruses
  • Build proteins
  • Produce genetic materials
  • Heal wounds

Zinc is especially important during early childhood, as it helps the body develop.

The problem

On their own, copper and zinc are mineral superheroes, capable of providing the body just what it needs. However, when taken together, they have the potential to become villains [3].

In short, a large dose of zinc can interfere with the body’s copper absorption. If you have a copper deficiency, taking zinc may exacerbate your symptoms. Copper deficiency symptoms include [3]:

  • Anemia
  • Hypopigmentation
  • Connective tissue disorders
  • Bone defects

Vitamins D, K, and E

Vitamins D, K, and E are similar to other essential vitamins and nutrients in that they help promote healthy bodily functioning. However, this trio of powerful vitamins may not make the perfect team when taken together.

Let’s take a closer look at each.

Vitamin D

Many people associate vitamin D, a fat-soluble vitamin, with strong bones and teeth. That’s because this crucial vitamin helps the body develop a durable bone structure. Furthermore, vitamin D helps [4]:

  • Prevent osteoporosis
  • Motor skill development
  • Strengthen the immune system

The good news is that your body produces vitamin D through sun exposure. You can also receive vitamin D through foods like milk and fatty fish.

Vitamin K

If your body needs vitamin D to help produce strong bones, it needs vitamin K to help the blood clot properly. Without sufficient vitamin K, your body may [5]:

  • Bruise and bleed more
  • Suffer from weak bones
  • Develop coronary heart disease

Luckily, many foods contain vitamin K. Foods rich in vitamin K include leafy greens and vegetables. Many people also supplement their diets with vitamin K supplements.

Vitamin E

Vitamin E is a vital nutrient because of its antioxidant properties. In short, vitamin E acts as an antioxidant, combating free radicals. Vitamin E can also support the immune system and help prevent blood clotting.

Vitamin E deficiencies are exceedingly rare. That said, people with vitamin E deficiencies may experience [6]:

  • Nerve and muscle damage
  • Trouble moving
  • Muscle weakness
  • Crohn’s disease

The problem

Some studies suggest that the body may not be able to absorb vitamin K as efficiently when taken with vitamins D and E.

As a result, taking a large dose of these three vitamins together may prevent vitamin K from clotting the blood effectively [7]. People with a vitamin K deficiency may be especially at risk.

Boost your health and wellness with vitamin supplements from Everlywell

While vitamin supplements can provide many benefits, especially for those with vitamin deficiency, combining the wrong ones can lead to nutrient absorption issues at best and serious health issues at worst.

Everlywell makes it easy to get information about the vitamins you need.

Rather than combining vitamins that don’t work together, our dietary supplements use evidence-backed, plant-based vitamins and nutrients. Our vitamin D3 supplement, for example, only contains vegetarian, gluten-free ingredients alongside vitamin D to bolster your health the right way. Browse all our vitamin and supplement options now.

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  1. Duncan A, Yacoubian C, Watson N, Morrison I. The risk of copper deficiency in patients prescribed zinc supplements. J Clin Pathol. 2015;68(9):723-725. doi:10.1136/jclinpath-2014-202837
  2. Copper. National Institutes of Health. Accessed September 27, 2022. URL
  3. Zinc. National Institutes of Health. Accessed September 27, 2022. URL
  4. Vitamin D. National Institutes of Health. Accessed September 27, 2022. URL
  5. Vitamin K. National Institutes of Health. Accessed September 27, 2022. URL
  6. Vitamin E. National Institutes of Health. Accessed September 27, 2022. URL
  7. Traber MG. Vitamin E and K interactions--a 50-year-old problem. Nutr Rev. 2008;66(11):624-629. doi:10.1111/j.1753-4887.2008.00123.x
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