Rickets is a condition that affects bone development in children. It causes the bones to become soft and weak, which can lead to bone deformities.
Rickets in adults is known as osteomalacia or soft bones.
The most common cause of rickets is a lack of vitamin D and calcium. Vitamin D largely comes from the exposure of the skin to sunlight, but it is also found in some foods such as oily fish and eggs. Vitamin D is essential for a child to form strong and healthy bones.
In rare cases, children can be born with a genetic form of rickets. It can also develop if another condition affects how vitamins and minerals are absorbed by the body.
Read more about the causes of rickets.
Who is affected
Rickets was common in the past, but it mostly disappeared in the Western world during the early twentieth century thanks to the fortification with vitamin D of foods such as margarine and cereal. However, there has been an increase in cases of rickets in the UK in recent years.
The number of rickets cases is still relatively small - less than 900 cases were diagnosed in hospitals in England during 2012 - but studies have shown that a significant number of people in the UK have low levels of vitamin D in their blood.
Any child whose diet does not contain enough vitamin D or calcium can develop rickets, but the condition is more common in children with dark skin (as this means more sunlight is needed to get enough vitamin D), children born prematurely, and children taking medication that interferes with vitamin D.
How to prevent rickets
Rickets can easily be prevented by eating a diet that includes vitamin D and calcium, as well as spending some time in sunlight.
The hands and face only need to be exposed to the sunlight for about 15 minutes a few times a week during spring and summer to provide you with enough vitamin D.
In some cases, vitamin D supplements may be recommended to reduce the risk of rickets.
Read more about preventing rickets, including information on good sources of vitamin D and calcium.
Signs and symptoms of rickets
Rickets can lead to bone pain, poor growth and deformities of the skeleton, such as bowed legs, curvature of the spine and thickening of the ankles, wrists and knees.
Children with rickets are also more likely to fracture their bones.
Read more about the symptoms of rickets.
When to seek medical advice
If your child has any symptoms of rickets, take them to your GP for a check-up.
Your GP will usually carry out a physical examination to check for any obvious problems. They may also discuss your child's medical history, diet, family history and any medication they are taking.
A blood test to measure calcium, phosphorous and vitamin D levels can usually confirm a diagnosis of rickets, although your child may also have some X-rays or possibly a bone density scan (DEXA scan). This is a special type of X-ray that measures the calcium content in the bones.
How rickets is treated
Rickets can be successfully treated in most children by ensuring they eat foods containing calcium and vitamin D or take vitamin supplements.
If your child has problems absorbing vitamins and minerals, they may need a higher supplement dose or a yearly vitamin D injection.
Read more about treating rickets.
Symptoms of rickets
Rickets causes a child's bones to become soft and weak, which can lead to bone deformities.
The signs and symptoms of rickets can include:
As your child gets older, the symptoms of rickets may also include waddling when walking, bent bones and muscle weakness or pain.
These symptoms can also affect adults who have soft bones (osteomalacia).
Some children with rickets may also have low levels of calcium in their blood (hypocalcaemia). This can make the symptoms of rickets worse and can also cause muscle cramps, twitching, tingling in the hands and feet, and fits.
When to seek medical advice
If your child has any symptoms of rickets, such as bone pain, delayed growth, muscle weakness or skeletal problems, take them to your GP for a check-up.
Causes of rickets
Rickets usually occurs because of a lack of vitamin D and calcium, although it can also be caused by a genetic defect or another health condition.
Lack of vitamin D and calcium
The main sources of vitamin D are:
Calcium is commonly found in dairy products (such as milk, cheese and yoghurt) and green vegetables (such as broccoli and cabbage).
Over time, a vitamin D or calcium deficiency causes rickets in children and osteomalacia (soft bones) in adults.
See preventing rickets for more information and advice to help ensure your child gets enough vitamin D and calcium.
Who's at risk
Any child who does not get enough vitamin D or calcium can develop rickets, but there are certain groups of children who are more at risk.
For example, rickets is more common in children of Asian, African-Caribbean and Middle Eastern origin because their skin is darker and needs more sunlight to get enough vitamin D.
Babies born prematurely are also at risk of developing rickets because babies build up stores of vitamin D while in the womb.
As the amount of vitamin D in breast milk varies, the Department of Health recommends that all pregnant and breastfeeding women should take a daily supplement of 10 micrograms ( g) of vitamin D. This ensures that the mother's vitamin D requirements are met and that adequate foetal stores are built up for early infancy.
Rare forms of rickets can also be inherited (passed on from a parent to a child).
For example, hypophosphatemic rickets is a genetic disorder in which the kidneys and bones deal abnormally with phosphate (calcium phosphate is what makes bones and teeth hard). This leaves too little phosphate in the blood and bones, leading to weak and soft bones.
Other types of genetic rickets affect special proteins in the body that are used by vitamin D.
Occasionally, rickets develops in children with rare forms of kidney, liver and intestinal conditions. These can affect the absorption of vitamins and minerals.
Most cases of rickets are caused by a vitamin D and calcium deficiency. Therefore, rickets is usually treated by increasing a child's intake of vitamin D and calcium.
Vitamin D and calcium levels can be increased by:
Sunlight also contains vitamin D, so you may be advised to increase the amount of time your child spends outside.
Your GP will advise you about how much vitamin D and calcium your child will need to take. This will depend on their age and the cause of the rickets. If your child has problems absorbing vitamins, they may need a higher dose.
See preventing rickets for more information about dietary sources of vitamin D and calcium, as well as advice about getting vitamin D from sunlight.
Treating complications and related conditions
When rickets occurs as a complication of another medical condition, treating the underlying condition will often cure the rickets. For example, people who have kidney disease and rickets may require dialysis (treatment that replicates many of the kidneys' functions).
If your child has a bone deformity caused by rickets, such as bowed legs or curvature of the spine, your GP may suggest treatment to correct it. This might be a brace to support the affected area of your child's body as their bones grow, or they may need surgery.
For hypophosphatemic rickets (where a genetic defect causes abnormalities in the way the kidneys and bones deal with phosphate), a combination of phosphate supplements and a special form of vitamin D is required.
Children with other types of genetic rickets need very large amounts of a special type of vitamin D treatment.
Supplement side effects
It is very unusual to get side effects from vitamin D, calcium or phosphate supplements if they are given in the correct dose.
However, if the dose of vitamin D or calcium is too high, it can raise calcium levels in the blood. This can result in a condition called hypercalcaemia. Symptoms of hypercalcaemia include:
See your GP immediately if you or your child has any of these symptoms.
There are several steps you can take to help prevent rickets. These include ensuring that your child has a healthy, balanced diet and spends some time outside in the sun.
Sources of vitamin D include:
Sources of calcium include:
If you have a restricted diet - for example if you are vegetarian or vegan - you may not be getting essential vitamins and minerals and may need to take vitamin supplements (see below).
Sunlight is a good source of vitamin D and is where most of our vitamin D comes from. The vitamin forms under the skin as a result of sun exposure.
In the UK, about 10-15 minutes of exposure on the hands and face when the sun is at its strongest (between 11am and 3pm) a few times a week during the spring and summer is enough for most people.
You won't get vitamin D from the sun if you wear sunscreen, but you should apply sunscreen with a sun protection factor (SPF) of at least 15 if you are outside for longer than 10-15 minutes. This will help protect your skin from sun damage.
Babies and young children have very sensitive skin that burns easily so they need to use stronger sunscreen and keep covered up when out in the sun.
In the UK, our skin isn't able to make vitamin D from sun during the winter (November to March) as the sunlight isn't strong enough. However, we can get vitamin D from our body's stores and from food sources during this period.
Most people can get all the vitamin D they need through their diet and by getting a little sun.
However, certain groups of people have an increased risk of developing a vitamin D deficiency and may need to take supplements to avoid getting rickets and osteomalacia (the adult form of rickets). These at-risk groups are discussed below.
Pregnant and breastfeeding women
The Department of Health recommends that all pregnant and breastfeeding women should take a daily supplement of 10 micrograms ( g) of vitamin D to reduce the risk of their child developing rickets.
In the UK, the Department of Health recommends the use of vitamin drops for all babies and young children aged six months to five years (or from one month if their mother has not taken vitamin D supplements throughout pregnancy).
However, the Department of Health says infants who are fed infant formula will not need vitamin drops until they are receiving less than 500ml of infant formula a day, as these products contain added vitamin D.
It is important that children in high-risk groups take vitamin D supplements. These include children who do not get enough vitamin D from their diet and those with certain medical conditions such as kidney disease. Your GP can advise you about how much vitamin supplementation is needed.
Other at-risk groups
Other people who have an increased risk of developing a vitamin D deficiency and who may need to take supplements include: