{"id":326296,"date":"2025-08-07T22:22:10","date_gmt":"2025-08-07T22:22:10","guid":{"rendered":"https:\/\/www.europesays.com\/uk\/326296\/"},"modified":"2025-08-07T22:22:10","modified_gmt":"2025-08-07T22:22:10","slug":"what-vitamins-should-not-be-taken-together","status":"publish","type":"post","link":"https:\/\/www.europesays.com\/uk\/326296\/","title":{"rendered":"What Vitamins Should Not Be Taken Together?"},"content":{"rendered":"\n

Popping a daily vitamin<\/a> is common practice\u2014as many as 75% of Americans<\/a> may do so. But some people aren\u2019t just stopping at one vitamin: They\u2019re supplement stacking<\/a>, combining several vitamins and minerals at once. <\/p>\n

Still, not all vitamins and supplements are designed to go together, especially in a more concentrated forms. With that, it\u2019s important to know what vitamins should not be taken together. <\/p>\n

Meet the experts: <\/strong>Sonya Angelone, R.D.N.,<\/a> is a nutritionist and registered dietitian based in San Francisco, California; Bruce Ruck, Pharm.D.<\/a>, is a toxicologist, adjunct professor at the Rutgers College of Pharmacy, and managing director at the New Jersey Poison Information and Education System; Zachary Mulvihill, M.D<\/a>., is an integrative medicine physician at Weill Cornell Medicine<\/p>\n

While supplements may seem like a harmless thing, that\u2019s not always the case, according to Sonya Angelone, R.D.N.,<\/a> a nutritionist and registered dietitian based in San Francisco, California. \u201cThey can talk to your DNA to affect how cells work, they can influence immune function, or they can contribute to an excess of a nutrient which can create a toxicity if not excreted properly,\u201d she says. If you pair the wrong supplements together, Angelone says they can work against each other or even lead to uncomfortable side effects for you. <\/p>\n

Plus, vitamins and supplements are part of a largely unregulated industry, making it crucial to know what you\u2019re taking, says Bruce Ruck, Pharm.D.<\/a>, a toxicologist, adjunct professor at the Rutgers College of Pharmacy, and managing director at the New Jersey Poison Information and Education System.<\/p>\n

Being harmed by vitamins and vitamin interactions is somewhat rare, \u201cbut it\u2019s common enough that it\u2019s a real concern and it does come up for me clinically,\u201d says Zachary Mulvihill, M.D<\/a>., integrative medicine physician at Weill Cornell Medicine. <\/p>\n

All of that said, experts agree that some people can benefit from taking vitamins and even several at once\u2014it\u2019s just important to make sure they don\u2019t work against each other and to get your doctor\u2019s buy-in. <\/p>\n

What Vitamins Should Not Be Taken Together?<\/strong><\/p>\n

If you\u2019re planning to put yourself on a vitamin regimen, Ruck says it\u2019s always a good idea to talk to a healthcare provider first. \u201cTalk to your physician, a nurse, or pharmacist\u2014check with somebody,\u201d he says. They can do bloodwork to determine if you have any deficiencies and take into account any other health conditions you may have or medications you are on. <\/p>\n

While this is not an exhaustive list, having your own baseline knowledge never hurts. And, while some of these are vitamins or minerals, others are herbal supplements that may have strong interactions. <\/p>\n

Zinc and calcium<\/strong><\/p>\n

Zinc<\/a> is a mineral that helps support the function of your immune system and metabolism, while calcium<\/a> helps to build and maintain bones and teeth, and supports muscle function and nerve transmission. <\/p>\n

While each has its own role in the body, they shouldn\u2019t be taken together. \u201cMinerals usually compete for absorption from the intestines,\u201d Angelone says. \u201cToo much of one mineral will block the absorption of the other one.\u201d Basically, if you take both of these at once, \u201cyou will absorb less of both,\u201d Angelone explains.<\/p>\n

Iron and zinc<\/strong><\/p>\n

Iron<\/a> is used in the body to make hemoglobin, a protein found in red blood cells. It\u2019s also required for growth and development, according to the National Institutes of Health<\/a> (NIH). Healthcare providers may recommend taking iron if you have anemia, a condition where the body doesn\u2019t have enough healthy red blood cells. But taking iron with zinc isn\u2019t recommended. \u201cThey compete for a common absorptive pathway,\u201d Dr. Mulvihill says.<\/p>\n

As a result, \u201cthat can decrease the absorption of either the iron, the zinc, or both,\u201d Ruck says. <\/p>\n

Iron and calcium<\/strong><\/p>\n

These two also don\u2019t play well together. \u201cHigh levels of calcium seem to decrease the absorption of iron,\u201d Dr. Mulvihill says. When these two are taken together, iron is usually absorbed less, Angelone explains. Iron deficiency could potentially occur in those at risk for anemia, she says. <\/p>\n

Magnesium and zinc<\/strong><\/p>\n

Magnesium<\/a> plays a role in several areas of the body, including regulating nerve function as well as calcium and blood sugar levels. But magnesium and zinc compete for the same pathways in the body, making it tough to absorb both at once, Angelone says. <\/p>\n

Magnesium is usually sacrificed when this happens, Dr. Mulvihill says. \u201cHigh doses of zinc can increase magnesium deficiency,\u201d he points out. <\/p>\n

St. John\u2019s wort and serotonergic supplements<\/strong><\/p>\n

St. John\u2019s wort is an herb with a wide range of uses, including for depression, stomach ulcers, colds, and wound healing, according to the National Center for Complementary and Integrative Health<\/a> (NCCIH). Serotonergic supplements are designed to increase levels of the feel-good hormone, serotonin, in the body to support good mood and sleep. These may include vitamin B6<\/a> and folate<\/a>, among others. <\/p>\n

Experts are especially wary of taking St. John\u2019s wort without the guidance of a healthcare provider. \u201cThis is a tricky supplement,\u201d Angelone says. Taking St. John\u2019s wort with a serotonergic supplement can cause excessive serotonin in your brain and lead to something called serotonin syndrome<\/a>, which is a potentially life-threatening reaction, she says. <\/p>\n

Ginkgo biloba and high-dose fish oil<\/strong><\/p>\n

Ginkgo biloba<\/a> is an herbal supplement that may impact blood circulation and cognitive function. Fish oil<\/a> is typically used to promote heart health and to reduce inflammation in the body. <\/p>\n

The big concern with taking these together is that they can impact your blood platelets and increase your risk of bleeding, Ruck says. It\u2019s also not a good idea to take either of these on top of a blood thinning prescription medication, Dr. Mulvihill says. \u201cAnyone on a blood thinner should be especially careful,\u201d he says. <\/p>\n

St. John\u2019s wort and ginseng<\/strong><\/p>\n

Ginseng<\/a> is an herb with a range of uses, including boosting energy and stabilizing blood sugar. \u201cTaken together, they can affect energy and mood by overstimulating the central nervous system,\u201d Angelone says.<\/p>\n

Dr. Mulvihill also stresses the importance of being cautious with St. John\u2019s wort. \u201cI do not use it with any of my patients because it has such significant risks for interactions,\u201d he says. Birth control is one of the medications this supplement may interact with, Dr. Mulvihill says.<\/p>\n

Which Vitamins Are Better When Taken Together?<\/strong><\/p>\n

While some vitamins and minerals shouldn\u2019t be taken together, there are certain combinations that may be better when they\u2019re used as a pair. Again, though, talk to your doctor before starting any new vitamins or supplements. <\/p>\n

Vitamin C and iron<\/strong><\/p>\n

Some iron supplements will include vitamin C for a very specific reason. \u201cVitamin C enhances the absorption of non-heme iron from the stomach,\u201d Angelone says. (Non-heme iron is a type of iron from plant foods.)<\/p>\n

Magnesium and vitamin D<\/strong><\/p>\n

Magnesium enhances vitamin D metabolism, Angelone says. \u201cBut [it] doesn\u2019t need to be taken at the same time since it isn\u2019t involved with the actual absorption of vitamin D,\u201d she explains. \u201cIt should just be taken in the same day.\u201d<\/p>\n

Vitamin D, calcium, and vitamin K2<\/strong><\/p>\n

If you\u2019re taking calcium, Angelone suggests looking for a supplement that also contains vitamins D and K2, or taking them as well. \u201cVitamin D enhances calcium absorption from the intestines into the blood, so more vitamin D means more calcium in the blood stream,\u201d she says. \u201cIn order for calcium to get into the bones, it needs to have an active transport molecule. Vitamin K2 is the only nutrient that activates this protein transporter.\u201d<\/p>\n

FAQ<\/strong>Can you take other vitamins with a multivitamin?<\/strong><\/p>\n

You can take a vitamin on top of a multivitamin, but experts say it\u2019s crucial to make sure you\u2019re not doubling up on some nutrients. \u201cI\u2019m surprised at how often this comes up,\u201d Dr. Mulvihill says. \u201cSome people will take a multivitamin that has a B complex and also take something for their hair that has B vitamins in it.\u201d<\/p>\n

It\u2019s also important to be mindful of potential interactions, Ruck says. \u201cFor example, if your multivitamin has iron and you take a separate one with zinc, they may interact,\u201d he says. <\/p>\n

Can you take medication at the same time as a vitamin?<\/strong><\/p>\n

It\u2019s a good idea to talk to your healthcare provider about this one. \u201cSome vitamins and minerals can interact with medications, especially antibiotics,\u201d Ruck says. \u201cTaking them together could make your medication ineffective.\u201d<\/p>\n

How can you know if you need a vitamin?<\/strong><\/p>\n

The best way to know for sure is to talk to a healthcare provider and undergo testing. \u201cIt\u2019s always better to test for a deficiency than to supplement blindly,\u201d Dr. Mulvihill says. <\/p>\n

What should you do if you take vitamins that may interact?<\/strong><\/p>\n

If your doctor recommends that you take vitamins that may interact, Ruck says it\u2019s a good idea to separate them by a few hours. That may mean taking one supplement in the morning and the other at lunch. <\/p>\n

Bottom line<\/strong><\/p>\n

While supplements are incredibly popular and easily accessible right now, experts say it\u2019s still best to check in with a healthcare provider before diving in. If you\u2019ve already started a vitamin regimen, Dr. Mulvihill suggests that you still talk to a healthcare provider. <\/p>\n

Dietary supplements are products intended to supplement the diet. They are not medicines and are not intended to treat, diagnose, mitigate, prevent, or cure diseases. Be cautious about taking dietary supplements if you are pregnant or nursing. Also, be careful about giving supplements to a child, unless recommended by their healthcare provider.<\/p>\n

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