Vitamin C is one of the most popular supplements in the world. It is known for helping immunity, skin health, and wound healing. During the COVID-19 pandemic, sales of vitamin C soared as people searched for ways to protect themselves from infection. Many assumed that taking more would mean better protection. But new research suggests otherwise. While moderate vitamin C intake is essential, too much can have unwanted effects. When taken in large doses, vitamin C can increase the risk of kidney stones. The concern is not about food-based vitamin C but high-dose supplements that people take daily. Understanding this connection helps avoid unnecessary health problems.Link between high-dose Vitamin C and kidney stone formationWhile vitamin C is important for the body, more is not always better. Once consumed, vitamin C is broken down into oxalate, a compound that binds with calcium to form kidney stones. These stones can be extremely painful and may lead to serious complications if left untreated.According to the same research, people who take about one gram of vitamin C per day may increase their urinary oxalate levels by up to 60 percent. This is the same amount found in many “immune booster” products and powders. Other medical findings have shown that men who regularly take high doses of vitamin C supplements are almost twice as likely to develop kidney stones compared to those who do not.Food sources such as oranges, guavas, or bell peppers do not pose the same risk because the body absorbs and regulates natural vitamin C differently. The real concern arises from daily supplement use that exceeds recommended limits.Increasing online searches for Vitamin C during the pandemicA study published in Cureus found that online interest in vitamin C rose sharply during the early months of the COVID-19 outbreak. Researchers analysed search data between 2018 and 2022 using Google Trends. They discovered that public interest in vitamin C increased nearly four times in March 2020, just as the pandemic began spreading globally.Even after the first surge, searches for vitamin C remained consistently higher than before. People were turning to supplements in large numbers, driven by fear and uncertainty. The study also found that around one-third of top websites claimed vitamin C could treat or prevent COVID-19, even though there was no clear medical evidence to support that claim.These findings highlight how online behaviour often mirrors public anxiety. When reliable health information is limited, people are more likely to turn to the internet for quick answers, which may not always be accurate.The problem of online misinformation about supplementsThe study also looked at the accuracy of popular health websites and found that many did not mention the possible risks of too much vitamin C. None of the top results warned users about kidney stone formation. This means that people searching online were often getting one-sided information.This problem became worse during the pandemic, when social media posts and unverified articles promoted vitamin C as a cure or shield against COVID-19. Misinformation spread quickly, often shared by well-meaning individuals who did not realise the claims lacked scientific backing.Health experts have since emphasised the importance of checking reliable sources before following supplement advice. Dr Sood, in a video posted on Instagram, summed it up well: “When you realise too much Vitamin C doesn’t just ‘boost immunity’, it can drive kidney stones. With supplements, more isn’t always better.”This simple message underlines how something widely viewed as harmless can have hidden effects when used carelessly.How to take Vitamin C safely and protect kidney healthVitamin C is essential, but moderation is key. The recommended daily intake for adults is about 65 to 90 milligrams, which most people can easily get from a balanced diet. Citrus fruits, strawberries, kiwi, tomatoes, and leafy vegetables all provide enough vitamin C naturally.Supplements should only be used when dietary intake is low or when prescribed by a doctor. High doses, especially above 1,000 milligrams per day, should be avoided unless medically necessary. People with a history of kidney stones or kidney problems need to be particularly cautious.It also helps to stay well-hydrated, as water supports the kidneys in flushing out excess oxalate. Regular check-ups and honest conversations with doctors about supplement use can prevent problems before they start. As the saying goes, prevention is better than cure.The findings from Cureus serve as a reminder that even everyday vitamins can have downsides when overused. Vitamin C is vital for good health, but large doses do not offer extra protection and may instead lead to kidney stones. During the pandemic, many people turned to supplements out of fear, often influenced by online misinformation. However, real immunity comes from balanced nutrition, adequate sleep, and medical guidance, not from excessive pill use.The safest approach is simple: meet your vitamin C needs through food, use supplements carefully, and trust verified medical advice. The body only needs what it can use. Anything beyond that can turn a helpful nutrient into a hidden risk.Disclaimer: This article is for informational purposes only and should not be considered medical advice. Please consult a healthcare professional before making any changes to your diet, medication, or lifestyle.Also Read | Even a sip of alcohol could raise your dementia risk; new study reveals