What vitamins should not be taken together?

Not all vitamins are meant to be taken together. Here’s your guide to staying safe and maximizing your vitamin stack for optimal performance.
What Vitamins Should Not Be Taken Together?
minute read

We all step onto the path of wellness with the best intentions. Some want more energy, better cognition, or freedom from tension or discomfort. As we begin this quest, certain supplements like vitamins and minerals can help us progress toward better health and quality of life. 

However, even with the health benefits of vitamins widely discussed, it’s easy to overdo these dietary supplements or use them incorrectly in high doses. You might not associate vitamin and mineral supplements with side effects or health hazards, but these essential nutrients have their limits as well.

In this article, we’ll discuss which vitamins should not be taken together, and how to navigate the world of supplements safely for maximum benefits. You may learn that less is more when it comes to taking certain compounds, and some vitamins and minerals can counteract one another if taken in a short timeframe. 

Ultimately, true wellness means learning the ins and outs of supplements, including the right way to take them.

What are vitamins?

Before we talk about why certain vitamins are incompatible or interact negatively with one another, let’s start by looking at what vitamins really are.

Vitamins are organic compounds that contribute to the growth, functioning, and overall well-being of the human body. They’re different from macronutrients like carbs, fats, and proteins, but still play a key role in how the body survives and thrives.

With fat-soluble vitamins like A, D, and E, the body stores these in fatty tissue and must be absorbed along with dietary fats to register an effect. Water-soluble vitamins like B-complex and C are not stored in the body for long and require more frequent replenishment through food and supplement sources.

This distinction hints at what vitamin and mineral incompatibilities might look like as we examine the subject more deeply. Because fat-soluble vitamins are stored in higher amounts for longer within the body, we likely need to be more careful when ingesting these over time and paying attention to our supplement strategies as a result.

Why are certain vitamins and minerals incompatible?

Whether you’ve just started taking vitamin supplements or taking the advice of a registered dietitian, there are some obstacles to watch out for when you take vitamin compounds daily.

Certain vitamins and minerals are considered incompatible for a range of different possible reasons, especially when doses rise above their daily recommended averages. After all, the body constantly seeks a state of homeostasis, whereby all mechanisms and nutrient levels are balanced in the most efficient, economical way possible. 

When one of these nutrients rises in concentration due to excessive intake, certain chemical interactions can be negative. More commonly, the effectiveness of these compounds is diminished, and you flush out excess concentrations naturally.

Overconsumption and toxicity are arguably a bigger problem than incompatibility between organic compounds, especially with fat-soluble vitamins like vitamins A, vitamin E, and vitamin K. High doses of vitamins that are fat-soluble can build up in fat cells over time, so it’s wise to limit large doses and be on the lookout for related symptoms over time.

What are the health risks that come with certain vitamin stacks?

When we refer to organic compounds being incompatible or not working together, recognize that we’re usually not talking about a toxic or hazardous reaction that occurs in the body. 

You may generate mental images of science experiments gone wrong or some other dangerous scenario. But realistically, the main concern is rendering certain compounds ineffective and running the risk of minor side effects.

With that in mind, it’s better to play it safe when mapping out your supplement strategy and work within the recommendations of your healthcare provider or the National Institutes of Health's suggested serving amounts.

What vitamin combinations should you avoid?

If you’re looking to start taking more vitamins and supplements, there are certain vitamins that are generally best when taken separately, rather than together. Here’s a closer look at combinations you may want to avoid. 

Calcium and iron

Taking calcium supplements alongside an iron supplement isn’t necessarily risky, but it might limit the effectiveness and absorption of these individual minerals. Both of these compounds use the same transport proteins when absorbed into the small intestine, meaning they compete for the use of this mechanism when they enter the system at the same time. 

Over the long term, this reduced absorption can lead to an over-concentration of one mineral and a shortage of the other. While you shouldn’t drastically alter your supplementation approach here, spreading out your supplement intake throughout the day can help avoid this unnecessary competition. 

Zinc and copper

Zinc supplements and foods rich in this mineral are popular for supporting the immune system, while copper is key for cardiovascular health and circulation. However, high doses of zinc can limit copper absorption by triggering a specific protein in the small intestine that prioritizes zinc over copper.

To avoid overdoing zinc and missing out on copper, make sure these compounds are taken separately, ideally with varied sources throughout the day. Leafy greens offer a great way to get copper, while zinc supplements are best taken leading up to bedtime for their help with sleep.

Vitamin C and vitamin B12

The relationship between vitamin C and B12 shows that these two compounds don’t get along in the digestive tract. Studies have found that vitamin C can degrade the integrity of B12 in a high-acidity environment like the intestines, meaning you miss out on the benefits of B12 like improved nerve function and DNA preservation.

If this is the case, simply take your vitamin C and B12 at least a few hours apart, and try to avoid taking your B12 supplement with fruit juice or citrus snacks. Both of these compounds are critical to holistic health, so find a healthy way to balance their intake throughout a 24-hour period.

Iron and green tea

It might sound like an unlikely rivalry, but iron supplements and green tea do not get along when consumed simultaneously. Green tea is rich in polyphenols, and these compounds bind to certain forms of iron and make the mineral less absorbable in the body. 

Since you don’t want to miss out on the benefit of iron, try to avoid taking iron supplements within a few hours of drinking green tea or taking capsules with green tea phytochemicals. Consider switching to coffee or another form of caffeine on days you take iron, especially if you rely on plant-based foods as your main source of iron.

What are some tips for timing your vitamin intake throughout the day and week?

Most of these vitamin and mineral incompatibilities aren’t significant enough to warrant serious concern, as you might expect with certain pharmaceutical product interactions. 

However, you might want to take a smarter approach with your supplements to get the most for your money and combat the off-chance of deficiencies over time. Here are some easy ways to time your intake more effectively and stay on top of your vitamin regimen moving forward.

Focus first on dietary nutrient intake

A balanced diet should be your top priority when navigating the world of vitamins and minerals. This is how you get the nutrients that matter most, and essential vitamins will naturally be part of a well-rounded way of eating over time.

By focusing on vitamin-rich foods, you’ll naturally reap the benefits of better blood pressure, heart health, and antioxidant protection. Combine this with hydration and electrolytes (giving you sodium, potassium, and more), and you have a strong foundation that likely won’t result in deficiencies or incompatibilities.

Stick to a single multivitamin or supplement source

It’s easy to get carried away and take multiple vitamin supplements, thinking that higher intake always results in a better outcome. As we’ve learned, this is simply not the case, and it may do more harm than good. 

That’s why we recommend using one reliable source of vitamins like our Supergreens Daily Gummies. This way, you can take two tasty gummies and not have to worry about heightened levels or deficiencies in any particular vitamin or mineral. It’s the safest, most sustainable way to get your micronutrients, and you won’t need to juggle several supplements throughout the day.*

Split your daily vitamin intake into two rounds

If you do need to supplement with B vitamins or minerals like magnesium, try taking them separately from your multivitamin or other compounds that may be incompatible. It can require some extra work to time these supplements correctly, but the effort pays off when you get to experience more benefits from each serving and enjoy peace of mind.

Take vitamin supplements with food or dietary fat sources

It’s always a good idea to take vitamins with food and dietary fat sources like omega-3 fatty acids. For instance, pair your daily multivitamin with some fish oil or a spoonful of coconut oil, ensuring the compounds are released and absorbed correctly. This will also add a satiating factor to your supplement routine and help you manage calories more effectively later on.

The bottom line

Vitamin and mineral supplementation should be easy and straightforward — that’s why we created Supergreens Daily Gummies and encourage a food-first approach to nutrient intake at any stage of life.

However, it never hurts to take a more conscious, science-backed approach to supplementation, even if that means spacing out your vitamin intake between two or three sessions during the day. Every bit counts, so learn what your body needs and make sure your health and well-being comes first.


The safety of commonly used vitamins and minerals | NIH

Safety considerations and potential interactions of vitamins: should vitamins be considered drugs? | NIH

What is vitamin D toxicity? Should I be worried about taking supplements? | Mayo Clinic

Vitamin B12 | Linus Pauling Institute

Green tea and iron, bad combination | Penn State University

Iron Supplement (Oral Route, Parenteral Route) Precautions | Mayo Clinic.