Why do children need vitamin D?

Children need vitamin D for bone growth and development. Babies developing in the womb also need it for the same reason.

Vitamin D helps children absorb calcium. It can also help their immune systems fight off germs.

How children get vitamin D: sunlight

Sun exposure is the main source of vitamin D for children in Australia. Your child needs sunlight on their skin for their body to make vitamin D.

Experts aren’t sure exactly how much sun exposure children in Australia need for adequate levels of vitamin D. But we do know that the amount of sun exposure your child needs depends on their location in Australia and the time of year.

The amount of sun exposure children need for adequate vitamin D also depends on skin colour. People with very dark skin need 3-6 times more sun exposure to make adequate vitamin D than people with light skin.

How much sunlight does your child need to make enough vitamin D?

Here’s a guide to how much sun exposure your child needs to make adequate vitamin D, without putting your child’s skin at risk of sun damage.

Adelaide, Hobart and Melbourne

• In summer, a few minutes most days of the week should be enough.
• From May to August, 2-3 hours per week should be enough.

During winter, children with dark skin living in Adelaide, Hobart or Melbourne might not get enough vitamin D from sun exposure alone. It’s a good idea to ask your GP about whether your child might also need a vitamin D supplement.

Brisbane and Darwin

A few minutes most days of the week should be enough right through the year.

Canberra, Perth and Sydney

• In summer, a few minutes most days of the week should be enough.
• In June and July, 2-3 hours per week should be enough.

Be sun smart – no matter where you live and what time of year it is

No matter where you live in Australia, be careful about how much sun your child gets on their skin. Too much sun exposure can lead to sunburn, skin damage and even skin cancer. This is why it’s important to use sun protection.

During summer, especially between 9 am and 4 pm, make sure your child stays safe in the sun with sunscreen, a hat, sunglasses, clothing that keeps the sun off, and access to plenty of shade.

To get more information and advice about how much sun exposure is right for your child, speak with your GP.

How to top up your child’s vitamin D through food

Vitamin D-rich foods can add to the vitamin D your child gets from sun exposure. Most children won’t get enough vitamin D from food alone.

There aren’t many vitamin D-rich foods.

Foods naturally rich in vitamin D

• Fatty fish (salmon, herring, mackerel and sardines)
• Liver
• Egg yolks
• Mushrooms grown outdoors or in UV light

Foods with added vitamin D

• Breakfast cereals
• Low-fat dairy products
• Margarines

All infant formula contains vitamin D.

Foods with added vitamin D might have ‘fortified’ written on their packaging.

Outdoor exercise or play helps your child’s body make vitamin D. Your child can make the most of being out in the sun by doing daily physical activity outside.

Vitamin D deficiency in children

Vitamin deficiency happens when children don’t get enough vitamin D.

Children at risk of vitamin D deficiency

Children might be at risk of vitamin D deficiency if they:

• have very dark skin
• keep all their skin covered
• spend most of their time indoors and don’t get much sun exposure
• have a condition affecting the body’s vitamin D levels – for example, liver disease, kidney disease, coeliac disease or cystic fibrosis
• are taking medicines that can affect vitamin D levels
• have been breastfed for a long time and their breastfeeding mother has low vitamin D
• eat a vegan diet.

What are the signs of vitamin D deficiency in children?

Signs and symptoms of vitamin D deficiency in children include muscle weakness, bone pain, bone tenderness and fractures.

Severe vitamin D deficiency in children can lead to rickets, bone deformities, delayed motor development in childhood, and less bone development in adolescence.

How to treat vitamin D deficiency in children

Talk with your GP if you’re worried about your child’s vitamin D levels. Your GP can order a blood test, which is the best way to check vitamin D levels.

Mild vitamin D deficiency

Your GP might say that your child should get a bit more sun exposure.

Severe vitamin D deficiency

Your GP might say your child should take vitamin D supplements, as well as getting more sun exposure.

Vitamin D supplements

Your GP might recommend a vitamin D supplement if your child can’t get enough sun exposure. They might take a vitamin D supplement in one large, single dose, or they might take a supplement for several weeks or months.

You can also talk to a dietitian about vitamin D supplements.

If you take too much vitamin D from supplements, it can lead to too much calcium in your blood. This can cause problems in many parts of the body, including the kidneys, blood vessels, heart and bones. Always check with your GP or dietitian before taking a supplement or giving a supplement to your child.

Vitamin D, pregnancy, breastfeeding and bottle-feeding

Talk with your GP if you’re planning pregnancy, pregnant or breastfeeding and think you might have low vitamin D.

Recommendations for pregnancy

If you’re planning for pregnancy or are pregnant, you need to get enough vitamin D. This is important for your baby’s bone development. A baby’s vitamin D levels typically go up during development in the womb.

If you get enough vitamin D during pregnancy, your baby’s vitamin D levels after birth should be adequate to meet their needs until they start getting vitamin D from diet and sun exposure.

If pregnant women don’t get enough vitamin D, their children are at greater risk of developing rickets later in childhood – although this risk is reduced if children get enough vitamin D after birth.

Recommendations for breastfeeding

There isn’t a lot of vitamin D in breastmilk, so breastfeeding babies don’t get much vitamin D from breastmilk. If breastfeeding mothers have low vitamin D, they might not pass on enough vitamin D to their babies.

This is why breastfed babies’ vitamin D levels typically go down after birth until they start getting vitamin D from diet and sun exposure.

It’s recommended that breastfed babies with at least one other risk factor for low vitamin D, like very dark skin, have a vitamin D supplement of 400 IU or 10 micrograms (μg) a day. If you think your baby is at risk of vitamin D deficiency, it’s a good idea to talk with your GP before giving them a vitamin D supplement.

Bottle-feeding

Infant formula has higher levels of vitamin D, so formula-fed babies don’t usually need a supplement. If your formula-fed baby has more than one risk factor for low vitamin D, it’s still a good idea to talk with your GP.

Solariums, sometimes called sunbeds or tanning beds, should never be used to improve vitamin D levels or to treat vitamin D deficiency. All Australian states and territories have a ban on commercial solarium operators. Solariums increase the risk of skin cancer, and this risk far outweighs the benefits of any increase in vitamin D levels.