Children with 'prominent' forehead may in fact be suffering from a dangerous illness

Children with prominent, protruding foreheads and heavy brow ridges (otherwise known as frontal bossing) may be suffering from a serious illness first identified in 1645.

Rickets is a condition that affects bone development in children, sometimes leading to bone deformities. It is most commonly caused by prolonged vitamin D deficiency, as vitamin D helps the body absorb calcium from food.

Genetic defects can also play a role. Hypophosphatemic rickets, for example, is a genetic disorder where the kidneys and bones deal abnormally with phosphate such that there is too little in the blood and bones, leaving them weak and soft.

In addition to a pronounced forehead, swollen and painful wrists and ribs are another symptom of rickets. The mass-production of foods like margarine and cereal fortified with vitamin D meant that rickets all but disappeared in the western world during the early 20th century.

But malnutrition due to declining living standards is thought to have contributed toward an uptick in cases. According to the Big Issue, 10,986 people were diagnosed with malnutrition after being admitted to English hospitals last year, including 312 children - a number that has quadrupled in 15 years and doubled over the last decade.