Here’s how to know which vitamins and minerals are best not to take together and when to take them for best results.
What Vitamins You Shouldn't Take Together
With so many supplements on the shelf, it can be hard to know which ones to take – or whether some combinations are better left apart.
Quick Guide – What Vitamins to Not Take Together Chart
| Do Not Take Together | Why Not? | Better Option |
|---|---|---|
| Iron + Calcium | These minerals compete for absorption in the gut. | Take at different times of the day. |
| Iron + Zinc | Both are absorbed similarly and can compete for uptake. | Separate by a few hours. |
| Iron + Vitamin D | Vitamin D may interfere with iron absorption. | Take at different times of the day. |
| Magnesium + Iron | Can reduce absorption when taken together. | Take separately. |
Why Some Vitamins and Minerals Don’t Mix Well
Nutrient Absorption Conflicts
Sometimes, it's not just what you take, but when you take it. Certain vitamins and minerals compete for absorption in the body, especially those that share similar transport pathways.
For example, iron and zinc, and are all essential nutrients, but taking them together may reduce how efficiently each is absorbed. If you’re wondering what vitamins should not be taken together, this kind of interaction is a common reason.
Spacing these minerals out throughout the day, rather than taking them at the same time, can help support absorption of each nutrient.
If you’re taking any prescription medicines, always check in with your healthcare professional before introducing new supplements.
Doubling Up on Nutrients
It’s easy to unintentionally overdo it on certain nutrients, especially when taking a mix of multivitamins, powders, and individual supplements.
For example, a multivitamin might already contain magnesium and calcium, so adding separate magnesium or calcium supplements could lead to excessive intake of these minerals.
That’s why it’s important to always check your product labels, be aware of any ingredients that might be overlapping, and seek guidance if you’re unsure.
How to Take Your Supplements
Timing Is Everything
When it comes to getting the most from your supplements, timing can make a big difference. Iron is best absorbed on an empty stomach, ideally in the morning, though some people may need to take it with food to avoid tummy discomfort.
Calcium is best taken with meals or later in the day, while magnesium is often taken in the evening, as some people find it fits well into their evening routine. Vitamin D, being fat-soluble, is best absorbed with a meal that contains healthy fats.
Follow The Label
It’s important to always follow the dosage instructions on your supplement label, more isn’t always better. Each product is carefully formulated to deliver a specific amount of nutrients,
Speak to a Health Professional
If you're taking prescription medications or managing a specific health condition, it’s always best to talk to your doctor or a qualified health professional before starting any new supplement.
A professional can help you identify what’s appropriate for your individual needs and help you avoid combinations that might not be right for you.
Vitamins and Minerals That Work Well Together
Vitamin C + Iron
Some nutrients actually help each other out, just like vitamin C and iron. Vitamin C supports the body’s ability to absorb non-haem iron (the type found in plant-based sources and supplements), making it a helpful partner when iron levels need support.
A simple way to pair them is to take your iron tablet with a glass of orange juice or alongside a vitamin C-rich snack like strawberries or kiwifruit.
Vitamin D + Calcium
Vitamin D plays an important role in helping the body absorb calcium effectively. They’re a key combination for strong, healthy bones.
Taking these two nutrients together, particularly if your diet is low in calcium-rich foods, may help support bone health across all stages of life.
While they’re often paired in supplements, vitamin D can also be found in fortified foods and gained through safe sun exposure.
Magnesium + B Vitamins
Magnesium and B vitamins are often found together in formulations designed to support energy production.
They work in complementary ways to help the nervous system function, something especially important during busy or demanding times.
If you’re wondering how much magnesium to take daily, it depends on your age, gender, and health needs. But it’s always a good idea to check with a healthcare professional.
Understanding why we need magnesium, from supporting muscle function to supporting energy levels, can help you make informed choices about how much you require and when to fit it into your day.
Final Tips for Supplements
When it comes to taking vitamins and minerals, a little planning goes a long way. Always read the label and follow the directions for use and avoid exceeding the recommended daily intake.
Keeping a supplement log or checklist can help you stay on top of what you’re taking and when, especially if you’re using multiple products.
It’s also a good idea to check for ingredient overlap, particularly in multivitamins or combination supplements, to avoid doubling up on any nutrients.
Frequently Asked Questions
Can I take iron and vitamin D together?
It's best to take them at different times to avoid reduced iron absorption.
Can I take vitamin D and magnesium together?
These can generally be taken together, but if you're unsure, ask your healthcare professional.
Can I take all my supplements at once?
Not always. Some nutrients compete for absorption — spacing them out helps.
Can I have too much magnesium?
Yes, excessive magnesium (especially from supplements) may cause diarrhoea, always read the label and follow the directions for use. Follow dosage instructions.
