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Gummy vitamins taste like candy and make you healthier, right? What’s not to like?
The global market for vitamin gummies has exploded in recent years, valued at nearly $9 billion in 2025 and predicted to double by 2033. Nearly a quarter of that consumption is in the United States.
Driving this boom is the idea that these chewable vitamins are a convenient, tasty way of improving general health—helped, as often happens, by some savvy marketing campaigns.
But, is there a dark side to these squishy health boosters? America’s Poison Centers’s national helpline receives more than 60,000 calls about possible vitamin poisoning every year, mostly from parents alarmed after their children have accidentally gorged on the chewy sweets. Are they right to be worried?
Dr. Kait Brown, clinical managing director at America’s Poison Centers, is keen to reassure anyone scared they can overdose on gummy vitamins.
“It’s very rare that kids are having symptoms when the Poison Center is contacted about multivitamins,” she says. “There is a margin of safety with all of them.”
Iron in gummy vitamins can pose real risks
The main exception when it comes to acute poisoning risk from multivitamins, she explains, is iron. Although iron boosts haemoglobin that helps blood carry oxygen around the body, it can also be corrosive to the stomach tract in high doses, causing nausea, vomiting, and diarrhea.
If any parents see these symptoms in their children after consuming products containing iron, she urges them to call the Poison Center helpline immediately at 1-800-222-1222.
“We can often get these kids the treatment they need in a timely fashion so they don’t progress to the later stage of iron toxicity,” she says. This severe poisoning is known as metabolic acidosis. “It changes the way your organs function so you have potential multi-organ failure. It’s fatal if untreated.”
In the 1980s, she says, deaths from iron poisoning were much more common. Nowadays, however, they are extremely rare. This is partly thanks to stricter regulation requiring child-resistant packaging for products containing iron. Many multivitamins also now leave out iron altogether.
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But although the risk of immediate overdose from most vitamin supplements is very low, they can carry more insidious risks.
“Where we mostly run into concerns with vitamin toxicity from multivitamins is chronic overuse,” Dr. Brown says.
Why you need to pay attention to fat soluble versus water soluble vitamins
There are two main types of vitamins: fat-soluble vitamins such as A, D, E and K, and water-soluble vitamins such as B and C.
“Some vitamins are taken more into the tissues and bones in our bodies, those are the fat-soluble ones,” Dr. Brown explains. “Water-soluble ones aren’t really taken up in that way and are more likely to be just flushed out of the system.”
In other words, if you consume too many water-soluble vitamins, you’ll probably just pee them out.
More care, on the other hand, should be taken with fat-soluble vitamins. As these are stored in our tissues, there is a greater risk that excess consumption can build up in the body over time.
Vitamin D, for instance, is essential for absorbing calcium and phosphorus, giving us healthy teeth and bones. But if taken to excess, vitamin D can cause calcium to build up in the blood. Early symptoms of this include weakness and vomiting. In extreme cases, overconsumption of vitamin D can even affect heart and brain function.
Also be aware of vitamin A
Vitamin A is another leading culprit of chronic vitamin toxicity.
“It can cause some liver damage, and there’s also things like bone pain and hair loss associated with it over time,” Dr. Brown says. “But this is only if you’re consuming many, many [gummy vitamins] a day over many days.”
In general, she says, there is no reason to fear these squishy supplements, which can be a useful boost to a healthy diet. But it is important to familiarize yourself with the vitamin content of each product, be aware of recommended daily maximum doses for different age groups and keep the containers away from children.
“They’re in a lot of homes, and especially kids under five don’t necessarily understand the difference between candy and medication,” she says. “It’s something they know tastes good and if they’re left alone with the product, they might say, ‘Oh, I want a few more of these today.’”
What’s more important than vitamins? Eating a balanced diet. Image: Getty Images / Kseniya Ovchinnikova
The importance of holistic health
While the dangers of multivitamins are generally low, dietician and gut health expert Dr. Emily Leeming warns against relying on them for a healthy diet.
“I think there is a place to have a multivitamin for certain people who are struggling to get that from food alone,” she says. “[But] we need to be a bit more cautious about thinking that taking supplements is an easy fail-safe. We don’t want to be doubling up where we don’t need to be.”
She points out that many gummy vitamins are loaded with sugar, or with sugar alcohols that can cause bloating in high doses.
Moreover, topping up on certain vitamins is no substitute for a healthy, balanced diet.
“Most of these multivitamins might contain a range from five to 30 different nutrients and micronutrients,” she says. But food contains 26,000 biochemicals that play many different roles in the body. “So, by eating the whole food source, there are so many other benefits that are coming with that besides that one nutrient we’re trying to get more of.”
The final concern is cost, with some high-end formulas costing as much as $30 per bottle. The FDA doesn’t regulate the supplement market in the same way it does for medicines, making it difficult to know whether the health claims of more niche products are based on real evidence.
“Don’t feel like you’ve got to get sucked into some powerful marketing and need to spend on expensive products,” Dr. Leeming says. “If you want to make changes for your health, first try and spend that money on making and eating healthy food.”
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