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<\/p>\nRojina Shams Nateri, pharmacist at Roseway Labs, told vitamin users they could be making a huge error when taking supplements. It can lead to having a big impact on their health<\/p>\n
07:07, 01 Mar 2026Updated 07:56, 01 Mar 2026<\/p>\n
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Vitamin users have been issued a warning (stock image)(Image: Getty Images)<\/p>\n
Thousands of people take supplements, as many report they can help to boost your health as well as your quality of sleep.<\/a> However, if you regularly take vitamins, you need to pay attention, as you could be making a big mistake.<\/p>\n Sometimes it feels like, everywhere we look, there are people advising us to take more supplements<\/a> as they\u2019re good for the hair, skin and bones. While they can support health<\/a> in many ways, there are also some things you need to know about using them and Rojina Shams Nateri, pharmacist at Roseway Labs<\/a>, has warned that sometimes supplements can actually can do more harm than good.<\/p>\n She recently shared some expert advice<\/a> to tell people exactly what they should be aware of. In fact, a doctor has also previously said some have very little benefit<\/a>.<\/p>\n “One of the most common mistakes I see is stacking winter supplements that contain the same ingredients,” said Rojina. “You might take a multivitamin, an immune blend and extra zinc or vitamin C, and suddenly you\u2019ve tripled your intake without meaning to.”<\/p>\n Many products contain zinc, vitamin C and B vitamins. Taken together, they can push you well beyond the recommended nutrient reference value (NRV), leaving many people quietly overdosing on vitamins they believe are harmless.<\/p>\n Assuming high doses are safe is a really common mistake. “People think vitamins are risk-free because you can buy them over the counter. That\u2019s not true,” Rojina explained.<\/p>\n Zinc above 9.5mg a day for men and 7mg for women can actually weaken immunity long-term by interfering with copper absorption. Vitamin D above 100 micrograms (4,000 IU) can raise calcium to dangerous levels.<\/p>\n Vitamin A builds up in the body, but doses above 1.5mg (1,500mcg) can damage the liver and pregnant women should avoid high doses completely. Even vitamin C has limits.<\/p>\n She added: “The UK recommended intake is 40mg per day, and absorption becomes less efficient at higher doses. Once intake reaches anything above 200mg a day, excess vitamin C is largely excreted by the body.”<\/p>\n Perhaps the most dangerous problem with supplements is how they can impact medications. “Calcium, magnesium, iron and high-dose vitamin C can reduce the absorption of antibiotics, thyroid medication and some blood pressure drugs,” Rojina warned.<\/p>\n “If you\u2019re taking prescription medicine, even short-term, always check before adding supplements.”<\/p>\n What’s worth taking?<\/p>\n “In winter, vitamin D is sensible for most adults,” she said. “Omega-3 with EPA and DHA supports brain and heart health. Magnesium can help with sleep and muscle tension.<\/p>\n “Supplements should support your health, not replace good sleep, balanced meals and medical advice. If you\u2019re unsure, ask your pharmacist. It could save you from doing more harm than good.”<\/p>\n Little you may know, taking too many vitamins can be harmful, as it has the potential to lead to toxicity, organ damage and other health issues. While small amounts are essential, excessive doses, particularly of fat-soluble vitamins (A, D, E, K), are stored in the body rather than excreted, which can cause bad side effects.<\/p>\n As well as this, regularly taking multiple supplements, or fortified foods (cereals, bars) alongside pills, can lead to overdosing. This is why you need to be vigilant.<\/p>\n Always consult a doctor before starting supplements, especially if you are pregnant, elderly or already have any health conditions. Expert guidance should always be sought first.<\/p>\n Ensure our latest headlines always appear at the top of your Google Search by making us a Preferred Source. <\/strong>Click here to activate<\/strong><\/a> or add us as your Preferred Source in your Google<\/a> search settings.<\/p>\n","protected":false},"excerpt":{"rendered":"Rojina Shams Nateri, pharmacist at Roseway Labs, told vitamin users they could be making a huge error when…\n","protected":false},"author":2,"featured_media":362355,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[277],"tags":[18,25437,135,19,17,508,5605],"class_list":{"0":"post-362354","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-nutrition","8":"tag-eire","9":"tag-expert-advice","10":"tag-health","11":"tag-ie","12":"tag-ireland","13":"tag-nutrition","14":"tag-vitamins"},"share_on_mastodon":{"url":"https:\/\/pubeurope.com\/@ie\/116153863602741231","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/posts\/362354","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/comments?post=362354"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/posts\/362354\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/media\/362355"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/media?parent=362354"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/categories?post=362354"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/tags?post=362354"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}