It’s something many children and adults do, but it can have some pretty unpleasant side-effects

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young boy biting fingernail

Woman sitting on kitchen worktop and eating a probiotic yoghurt

Three images of our writer�s new puppy which has helped her to start walking 10,000 steps per day

Woman looking in first aid bag with young daughter in background

pregnant woman in white dress holding stomach

A young girl scratching her arm where there is evidence of one of the common types of insect bites in the UK

Children in nursery singing nursery rhymes

Newborn baby wrapped in a wool blanket wearing a woolen hat

Parent high fiving child

Burger King sign

Mother talking to teenage daughter about sex

Teenage girl holding her phone