Are You Making a Big 'Error' When Taking Vitamin Supplements?
Vitamin supplements are widely believed to be a healthy addition to one's diet, but a pharmacist at Roseway Labs, Rojina Shams Nateri, has warned that taking them can sometimes do more harm than good. While they can support overall health, there are some important things to know about using them.
Many people take supplements to boost their health and improve their sleep quality. However, taking too many vitamins can be harmful, as it can 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.
One of the most common mistakes people make is stacking winter supplements that contain the same ingredients. For example, taking a multivitamin, an immune blend, and extra zinc or vitamin C can suddenly triple your intake without meaning to. Many products contain zinc, vitamin C, and B vitamins, and 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.
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’s not true," Rojina explained.
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. 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.
"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," Rojina added.
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.
"If you’re taking prescription medicine, even short-term, always check before adding supplements."
So, what's worth taking? "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.
"Supplements should support your health, not replace good sleep, balanced meals, and medical advice. If you’re unsure, ask your pharmacist. It could save you from doing more harm than good."
While supplements can be beneficial, it's important to be aware of the potential risks and to consult with a healthcare professional before starting any new supplement regimen.
