What’s all the fuss about vitamin D?
The short answer is that our bodies are built to make vitamin D using sunlight, and for us folks living up north, that isn’t really happening during the winter.
Vitamin D is a nutrient that our bodies use to help us absorb the calcium we eat, which we need to help make strong bones. Without vitamin D, calcium levels can drop, causing long-term effects on the strength of bones. The teens and twenties are the most critical time to build strong, healthy bones in order to avoid having weak bones and a risk of bone fractures later in life.
There is a lot of exciting research going on to figure out what other roles vitamin D might play. Some scientists think that low vitamin D levels could be related to obesity, diabetes, heart disease, inflammation, infections, and neurological diseases, though most of these links haven’t been proven yet. The reality is that most people have no symptoms to indicate to them (or their doctors) that their level of vitamin D is low.
So how can you make sure your teen is getting enough?
If your child’s skin is light and you live in a cloudless and sunny region, spending about 10-15 minutes in the sun every day is theoretically enough. For most people, especially in the winter, that’s not the case. One study showed that 1 in 4 teenage girls and 1 in 5 teenage boys had low vitamin D levels. That’s why in the U.S., foods like milk, orange juice, bread and cereal have vitamin D added. You can also try to serve foods that are naturally high in vitamin D, like egg yolks, salmon, and tuna. The goal is to get at least 600 IU (international units) every day. Many people choose to take vitamin D supplements, either alone or in the form of a multivitamin, but you can also look at nutrition labels to see if your child is getting enough. If your teen is taking a vitamin D supplement, it should have at least 600 IU of vitamin D. Sometimes a “dose” of a supplement will be more than one capsule, so be sure to read the instructions carefully.
Getting more than 600 units won’t hurt you unless you’re taking way too much – over 4000 units a day, or nearly 7 times the recommended daily dose. Overdosing on vitamin D can make you feel sick and in the long term can cause kidney damage. Usually, vitamin D overdose is caused by taking excessive amounts of supplements.
If you’re living up north, in a cloudier region, or your child has darker skin, their risk of having low vitamin D is higher. You should talk to your doctor to see if they need to have their level checked.
The rest of the story of strong bones
No matter how well you do at getting your teen’s developing bones enough vitamin D, it won’t help without two other key players: calcium and exercise. Since vitamin D’s job is to help the body absorb calcium, we have to give the body calcium so vitamin D can do its work. Teens need to take in about 1300 mg of calcium a day, and adults need at least 1000 mg. Again, check the nutrition labels to get a sense of how much calcium is in the foods you and your child eat. Heavy hitters include milk, yogurt, cheese, broccoli, kale, tofu, and beans. There’s also often calcium added to breads, cereals, and fruit juices. If your child just can’t get the recommended daily 1300 mg of calcium through food, they can get some added calcium in the form of a multivitamin (many of which are chewable and tasty!). Keep in mind that most vitamins contain 200-500 mg of calcium, so calcium-rich foods are still important.
If you have questions about whether supplements are right for your teen, talk to your doctor.
For a list of foods high in vitamin D and calcium, check out these links:
- http://youngwomenshealth.org/2012/12/27/vitamin-d/ has a table of vitamin D containing foods
- http://youngwomenshealth.org/2013/10/17/calcium/ has a table of calcium containing foods