Tuesday, July 16

Never Mix These 8 Supplements, Medical Experts Warn

It’s a common thing these days to have a vitamin deficiency. Luckily, there are also all types of supplements and diets that can help us restore our vitamin levels. But before you start gulping such supplements, it’s important to know that not everything we put into our bodies will have the desired effect.

On the contrary, some might work against us, especially when you combine more supplements or take them with over-the-counter (OTC) or prescribed medications.

As explained by Azza Halim, MD, a board-certified anesthesiologist, “there are plenty of supplements that are synergistic when combined versus those that actually can increase side effects, or increase or decrease absorption”. This doesn’t mean all combinations are wrong, but you do need to discuss with a doctor before mixing more supplements.

However, even with medical oversight, the following combination of supplements is to be avoided.

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  1. Calcium and iron

Supplements are meant to restore missing vitamins and nutrients but this is not possible if they are paired wrong and cancel each other out.

According to Trista Best, MPH, RD, a registered dietitian at Balance One Supplements, calcium and iron are among the worst combinations out there, undermining one another’s effects. “These two vitamins compete for absorption, and calcium will reduce the amount of iron your body is able to absorb, if any.”

The best combination for an efficient absorption of iron is iron and vitamin C supplements, says Best. Vitamin C helps iron absorption from non-heme irons aka plant sources. Just add some lemon to your water or consume fruits that are rich in vitamin C such as strawberries.

  1. Zinc and copper

Zinc and copper supplements are often used to strengthen the immune system. However, taking them at the same time will not have the desired results. On the contrary, as explained by certified nutritionist Jenny Dobrynina, they become completely useless if you don’t take them a few hours apart.

To make sure they do not compete for absorption in the body, maintain a proper amount of time between doses of zinc and copper.

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  1. Vitamin C and vitamin B-12

Another unfortunate combination is vitamin C and vitamin B-12. Dobrynina recommends the doses of vitamin C and vitamin B12 to be taken at least two hours apart.

Also, Mayo Clinic explains that combining these two supplements can lower levels of vitamin B-12 in the body; and you don’t want a B-12 deficiency as it can lead to anemia, lower levels of healthy blood cells, causing a general state of fatigue, memory issues and even problems with mobility and balance.

See also:Vitamin B12 deficiency in Older Adults: 10 Signs and Symptoms You Should Know About

  1. Vitamin E and vitamin K

Taking vitamin E and vitamin K together is also not the best idea due to their opposing effects on coagulation. According to various studies, vitamin E supplements can cause excessive bleeding in some individuals. To counteract such action, doctors recommend vitamin K. But taking them together annihilates the effect of vitamin K.

In a 2023 case study detailed in the Journal of Medical Case Reports, excessive supplementing of vitamin E can prevent vitamin K-derived coagulation factor synthesis. This can lead to serious bleeding incidents among which gastrointestinal bleeding and intracranial hemorrhage.

  1. Fish oil and ginkgo biloba

Fish oil and ginkgo biloba? Not together, if you want to make the most of each of their benefits. According to Jacek Szymanowski, a Precision Nutrition-certified nutritionist and health coach, taking these two supplements at the same time can have consequences on blood clotting.

“Combining these can increase the risk of bleeding due to their blood-thinning effects. Both supplements have anticoagulant properties, which can synergistically increase bleeding risk, especially in high doses or with other blood thinners,” says Szymanowski.

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  1. Folic acid (vitamin B9) and vitamin B-12

Another pairing that simply does not work, is folic acid and vitamin B-12. According to Dobrynina, is you take too much vitamin B9 and B12 (folic acid and folate), you will no longer be able to identify a potential vitamin B-12 deficiency.

According to various studies, among which one study published in the Cochrane Database of Systematic Reviews, in rare cases, excess consumption of these two vitamins can even lead to neurological problems. Vitamin B12 deficiency causes an anemia which has similar symptoms with the anemia caused by folate deficiency. Unlike folate anemia, b12 anemia can also cause serious problems to the central and peripheral nervous systems. Taking folic acid will help with the vitamin B12 deficiency but the risk of neurological problems will still exist, according to researchers.

  1. Vitamin C and copper

Vitamin C is crucial in the production of collagen, a protein that is know to do wonders with your skin. Vitamin C supplements are useful for different issues, among which fighting infections, reducing pain after surgery or lower blood pressure.

Copper plays an important part in the production of energy and in strengthening the structure of your body. Copper is usually taken by individuals with heart problems and Alzheimer’s disease.

Taking vitamin C and copper together will result in affecting the absorption of copper and preventing this mineral from doing its job.

Read also: People Ignore These 10 Cancer Symptoms Until It’s Too Late

  1. Iron and green tea

Iron is a mineral with an important role in ensuring that oxygen is transported from the lungs to the tissues. Usually, people with iron deficiencies, cancer and gastrointestinal problems are recommended to take iron supplements and associated diets to increase their iron intake.

Green tea has been found to boost mental health, reduce digestive problems and alleviate headaches. However, when green tea and iron are combined, the effect is on the absorption of the mineral. While for some it might not matter that much, iron is an important mineral for our bodies, so, it’s important that you take it as recommended by specialists. In this case, not mixed with green tea.


Taking a supplement seems like an easy alternative, especially when you can find everything you want online, at the local health or wellness store. However, not following a medical recommendation when taking supplements can do more harm than good. That’s because certain supplements cancel one another and you won’t benefit from anything if you take them together.

If you want to start a new supplement, it’s best that you discuss with your healthcare provider first. Supplementation is good when done right.

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