Millions of parents across the UK are being urged to watch for certain symptoms in their children, as vitamin D deficiency continues to affect worryingly high numbers of kids nationwide. Recent data reveals that almost one in five UK children have vitamin D levels falling short of government guidelines.

Known as the "sunshine vitamin", vitamin D plays a vital role in controlling calcium and phosphate levels in the body - both crucial for maintaining strong bones, healthy teeth and properly functioning muscles. A shortage can lead to rickets in children, where bones become weakened and softened, whilst adults may develop osteomalacia, triggering bone pain and muscular weakness.

A tell-tale symptom of rickets is bowed legs - when the legs bend outwards, leaving a conspicuous gap between the knees even when a child's feet are positioned together. That said, there are numerous other signs that can affect people of all ages.

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NHS guidance outlines the symptoms of rickets in youngsters and osteomalacia in grown-ups as follows:

• Swollen, painful wrists


• Pain in your back, shoulder, ribs, pelvis or legs


• Changes in the way you walk, such as waddling, not wanting to walk much or getting tired more easily


• Difficulty climbing stairs or getting out of a chair due to weak muscles


• Tingling, cramping or twitching of the muscles


• Breaking bones more often or after minor accidents, particularly the hips, lower back and feet

Parents are also advised to keep an eye on their child's growth. Children with rickets may be smaller than their peers, and their teeth might come through later than expected.

The Department of Health and Social Care advises that babies from birth to 1 year of age should have a daily supplement containing 8.5 to 10 micrograms of vitamin D all year round if they are breastfed, or formula-fed and consuming less than 500ml (about a pint) of infant formula a day, as infant formula is already fortified with vitamin D.

Children aged 1 to 4 years old should also receive a daily supplement containing 10 micrograms of vitamin D throughout the year. Most children over four - and adults - can produce all the vitamin D they need from sunlight between late March or early April through to the end of September.

During the autumn and winter months, the NHS suggests that everyone aged five and over (including pregnant and breastfeeding women) should consider taking a daily supplement containing 10 micrograms of vitamin D.