Do kids really need vitamin supplements? Scientists aren’t sure of their value.l (Bigstock/Bigstock)

I didn’t take vitamins growing up, so when I pass the supplements aisle at the grocery store and see bottle after gleaming bottle of children’s vitamins — in their enticing chewable, candy-flavored and cartoon-shaped glory — I can’t help but wonder: Is this really necessary? Do kids actually need supplements?

Many parents seem to think so. After all, about half of all young children (and 30 percent of teens) have taken dietary supplements, according to a 2004 study in Pediatric Annals. But scientists aren’t so sure.

“In general, the data regarding the benefits of taking vitamins is weak,” said biochemist Thomas Sherman, a neuroendocrinologist and an associate professor at Georgetown University School of Medicine. “And the data for children is pretty much nonexistent.”

What researchers do know is that most kids can get the nutrients they need from a healthful diet alone. Thanks to fortified milks, cereals and other foods, even children with less-than-ideal diets will still be okay, said William “Biff” Rees, head of the Virginia chapter of the American Academy of Pediatrics.

“I’ve been in practice a long time,” said Rees, who has been seeing families in Fairfax County for 37 years, “and I can’t remember seeing a vitamin-deficient child who didn’t have some sort of illness underlying the deficiency. It’s really hard to get vitamin-deficient — you almost have to work at it.”

So if your child is healthy, the bottom line seems to be that you don’t need to worry about a daily multivitamin or, for the most part, individual ones. Both Sherman and Rees recommend getting children the vitamins they need by focusing on food instead. Well-balanced meals with plenty of fruit and vegetables will provide kids with most of the vitamins and minerals they need for good health, along with great eating habits for the rest of their lives.

But there are a few exceptions where food alone won’t do the trick. The big one is Vitamin D, which is critical for building strong bones and may protect against cancer and some other diseases. Very few foods naturally have high levels of Vitamin D. Our bodies produce most of the Vitamin D we need through exposure to sunlight — or at least they are supposed to.

Although researchers disagree over how much Vitamin D we need — the Institute of Medicine recommends 400 to 800 international units a day, but some experts call for as many as 5,000 IUs — they know that many of us don’t get enough. That means kids, too: A 2008 study found about 40 percent of children have inadequate or less than optimal levels.

“We treat the sun like a death star, particularly when it comes to our kids,” Sherman said. “We slather on the sunscreen, we put on hats and long sleeves and even put shades on strollers, so we’re all chronically deficient in Vitamin D.”

That’s why many experts recommend Vitamin D supplements for kids of all ages, from babies to teens. Breast-fed babies especially should get that extra Vitamin D, because breast milk tends to have lower Vitamin D levels than fortified formulas do.

If your child has to follow a special diet or has special nutritional requirements, it may be worth considering other supplements. Kids who don’t eat meat or dairy products, for example, can miss out on key nutrients. “Vegetarian kids you can raise without supplements if you’re careful,” said Rees. “Vegan is difficult but not impossible to do.”

The risk with meat- or dairy-free diets is that your child may not be getting enough iron, calcium or B vitamins. Rees suggests working with your pediatrician to monitor your child’s diet and vitamin and mineral intake, adding supplements if there are concerns.

Medical conditions (such as cystic fibrosis) that limit how well a person can absorb vitamins from food may also make supplements important. In all cases, parents should ask their pediatricians what’s needed.

One supplement that’s especially popular right now is omega-3 fatty acid. In a national study that used data from 2002 and 2007, 40 percent of adults who said they take supplements reported using omega-3 fatty acid — usually in the form of fish oil pills — in the past 30 days.

There’s no question that omega-3s, which are found in salmon, sardines and other seafood, are important to health. They are thought to help protect heart and brain health as we age and to play a critical role in normal growth and brain development. Studies have linked omega-3s to a variety of things, including sharpened vision in infants and higher scores in reading and spelling in grade-schoolers.

So should your child take fish oil pills?

Here, again, experts recommend turning to food first. Eating fish twice a week will take care of your child’s omega-3 needs, Sherman said, without need for the supplements, which even in the sweetened gummy version have a slight fishy taste and smell.

“It’s cheaper to buy canned sardines or anchovies than to buy supplements, and you’ll get rich, high-quality omega-3,” he said. “Now, if your child doesn’t eat fish or you’re worried about mercury poisoning, then you can try to give your kids fish oil. But I have a hard time picturing them taking it.”

For Sherman, the supplement question became the subject of discussion in his own household. In the end, he and his wife decided to give their three children Vitamin D supplements and let healthful meals do the rest. But he says he understands wanting to use supplements as insurance to make sure your kids don’t miss anything they need.

“Whatever you decide, it’s not a choice you should have a tremendous amount of angst about,” Sherman said. “It isn’t a life-or-death choice, and if it gives you one less thing to worry about, then go for it.”

But he emphasized that it’s important not to overdo vitamins. So whatever you decide, be sure to talk to your pediatrician before taking action.