Vitamin B12. This is another crucial nutrient that can be harder to get on a plant-based diet. While vegans can get it from soy beverages and fortified cereals, it’s another reason why a multivitamin is a good idea.

Vitamin D. While the main source of vitamin D is sunshine (really!), most of us don’t spend enough time in the sun to get enough of it, and need to get it from our diet. If a child isn’t going to get it from fortified dairy products, then a supplement is the way to go. For younger children, the 400 IU that is present in most multivitamins is enough; older children may need more. Talk to your doctor about what is best for your child.

Fiber. This is one thing that vegan diets may actually have too much of, given that plants have a lot of fiber. The most common problem with getting too much fiber is that it can fill you up, making it harder to get enough of the calories and other nutrients you need. Giving children some refined grains like cereals can help, as can giving peeled fruits and cooked vegetables rather than raw.

What else should you consider?

It’s also helpful to consider the emotional aspects of being on a vegan diet. If your family is not vegan and your child is asking to be, it’s important to understand why. The reasons may be perfectly fine and healthy, but some children, especially teens, choose vegan diets in order to lose weight. If you suspect that your child may have an eating disorder, talk to your doctor.

Being on a restrictive diet can be difficult for some children, too, who may feel different from their peers, or excluded from group eating experiences like birthday parties. This is something that you should think about as parents and talk about as a family. If it’s important to you that your child adhere to a vegan diet in all settings, you should talk about strategies for navigating that, both in terms of making sure your child has food to eat in every setting, and in terms of helping them talk about their dietary choices with their friends.

Eating, after all, is about more than just feeding our bodies. Eating can and should be fun, no matter what diet we choose.

(Claire McCarthy, M.D., is senior faculty editor at Harvard Health Publishing.)