What is rickets?

Rickets is a bone disease that causes your bones to be soft and weak. It can be prevented with a good diet and some exposure to sunlight for vitamin D.

Rickets occurs in children, and occasionally teenagers. It does not occur in adults, as it only affects growing bones. Rickets is not common in Australia.

What are the symptoms of rickets?

If a child has rickets, their bones can bend slightly. Sometimes the bones of the legs will not grow straight. This is called having 'bow legs'. Sometimes the knees tilt inwards. This is called being 'knock-kneed'.

Other symptoms of rickets can include:

• swollen and sore wrists, knees and ankles
• teeth that appear late and have poor quality enamel
• the front fontanelle (the soft part at the top of a baby's head) being slow to close in babies
• soft skull bones
• poor growth
• being slow to crawl and walk
• breaking bones very easily

Sometimes babies and children with rickets can have muscle cramps or seizures due to low calcium levels.

What causes rickets?

Rickets only occurs in children (and occasionally teenagers) while they're growing. It is usually caused by low levels of vitamin D. Vitamin D forms in your skin when you are exposed to ultraviolet (UV) light from the sun. There is also vitamin D in some foods.

Low calcium or low phosphate levels can also sometimes lead to rickets. These minerals are needed for bone strength. Calcium and phosphate are found in milk and dairy foods.

Most children with low vitamin D alone do not get rickets. The risk of rickets is higher in babies and children who:

• breastfeed for a long time without starting solids at 4 to 6 months
• have a diet that does not have enough dairy products

Some kidney problems might also cause rickets. Kidney problems can make it harder for the body to absorb and use calcium and phosphate.

When should I take my child to see a doctor?

Take your child to see your doctor as soon as possible if they have any symptoms of rickets.

Also see your doctor if you're concerned about any aspect of your child's development.

How is rickets diagnosed?

If your doctor suspects rickets, your child will need to have a blood test to check their Vitamin D. The blood test will also check their:

• calcium level
• phosphate level
• kidney function

Your child might also need x-rays to check how well their bones are growing.

They might be referred to a paediatrician (doctor who specialises in the health of children).

How is rickets treated?

Your doctor may recommend changes to your child's diet. They may also refer you to a dietitian.

They might also recommend giving your child supplements to help your child get enough vitamin D, calcium and phosphate.

If your child has very low calcium, they will need to go to hospital. At the hospital, they will have treatment and have their heart checked.

Your child will need regular check-ups to check their vitamin D levels. They may also need regular x-rays to check on their bone growth.

Can rickets be prevented?

Healthy bones are vital to a child's physical growth and development. Eating the right foods and getting enough sunshine helps their bones develop. Good food and sunshine can prevent the development of rickets.

You can help prevent your child from getting rickets by:

• Seeing a midwife or doctor regularly during your pregnancy and having your vitamin D levels checked during your pregnancy. Have your child's levels checked if there are any concerns.
• Introducing solid foods when your baby is 4 to 6 months old.
• Making sure your child has enough calcium and phosphate in their diet — The Australian Guide to Healthy Eating will give you a good idea of which foods your child needs for healthy growth.
• Spending time outside in the sunshine. This will prevent vitamin D levels from dropping.

Some foods contain vitamin D. These include oily fish such as sardines, tuna and salmon. Milk and soy drinks with added vitamin D can also provide some vitamin D. However, including these foods in your diet is not usually enough to get all the vitamin D that is needed.

The best way for your child to get vitamin D is to get enough exposure to sunlight. The amount of time you need outside will depend on how dark your skin is. It also depends on where in Australia you live.

People with very dark skin may need more sun than people with light skin to reach the same levels of vitamin D.

It's important to find a balance between getting enough sun and staying protected from the sun. The SunSmart app is a great way to find out how much sun protection you need. It can also help you to plan when to get more sunshine.

Resources and support

If you are concerned about your child's development, see your doctor.

For more information about Vitamin D and sunshine, visit the Cancer Council website.

You can also call the healthdirect helpline on 1800 022 222 (known as NURSE-ON-CALL in Victoria). A registered nurse is available to speak with 24 hours a day, 7 days a week.