A Christmas Carol is a classic tale describing the life of the miserly Ebenezer Scrooge and how it was transformed after his encounter with the ghosts of Christmas Past, Present and Future. Truly a joyous and heart-warming story.

There is a dark side to this tale though, and that is the plight of the poor stunted and crippled child, Tiny Tim (no relation). Tiny Tim was the son of Bob Cratchit, the good-willed, but downtrodden employee of Scrooge. While only having a cameo in the book, Tiny Tim was described in vivid details as an ill and sickly child requiring a crutch and having his legs in iron braces.

Exactly what Tiny Tim was suffering from has been hotly debated by medical experts (who clearly have no life and nothing better to do with their time) since A Christmas Carol was published in 1843. Now the mystery has finally been solved.

Tiny Tim’s ill health was chronic, stunting his growth, suggesting something that persisted over his life. The first clue to solving the mystery of Tiny Tim\’s illness was that he lived in London during the early 1800s, which for the poor was crowded and plagued by blackened skies.

Following the great fires of 1666, London re-grew at a rapid rate, outstripping the supply of available wood so coal became the major source of fuel. Between 1750 and 1830, the use of coal increased 6-fold, fuelling not only domestic use, but also the ever increasing industrial production.

Adding to London’s dark skies from the coal, soot and sulfur dioxide, there was a massive 1815 eruption of the volcano Tambora in Indonesia which added more UV-blocking particles into the earth’s atmosphere.

All this pollution over London combined to filter out much of the sun’s UV radiation. That’s bad news for vitamin D synthesis in our body as the sun is the source of over 80% of it as vitamin D is only found in a limited range of foods such as oily fish, eggs and some fortified dairy foods. The diet of the working classes of London in the 1800s was scant in vitamin D-containing foods.

As a consequence of the black skies, children in London in the early 1800s were at much greater risk of the vitamin D deficiency disease called rickets. In rickets, a child\’s growing bones fail to develop properly resulting in soft and weakened bones, fractures, bone and muscle pain, and bone deformities.

The cause of rickets remained a mystery until the nineteenth century. During the time of Charles Dickens, a contagious factor or something in the air (known as a miasma) was thought to be the cause. To protect children against the miasma, they were kept indoors and covered from head to toe with clothing. Compounding this, many children worked from dawn to dusk in home-based textile manufacturing and so were required to stay indoors.

Poor Tiny Tim’s vitamin D deficiency gave him the well-described bone deformities and would also have put him at higher risk of pneumonia, upper respiratory infections and tuberculosis – all diseases that vitamin D helps to protect against. It is likely that Tiny Tim had a combination of rickets and very likely suffered from chronic tuberculosis.

How could Scrooge have improved the life of Tiny Tim? Bob Cratchit’s salary was likely to have only afforded him buying a limited range of foods. A better diet containing fish, dairy products and vegetables would certainly have helped.

The value of cod-liver oil, one of the highest sources of vitamin D, was not yet known as a cure for rickets. This was discovered some 25 years later when cod-liver oil was used to cure rickets in lion cubs in the London Zoological Garden. Tiny Tim could have also benefited from trips outside of the city to the countryside to get more exposure to the sun.

Sadly, A Christmas Carol fails to tell the reader what became of Tiny Tim and if he was ultimately cured. With more money coming to his family, their quality of life would have improved, giving Tiny Tim the best possible chance to beat his afflictions. Even today though, vitamin D deficiency still looms as a serious public health issue even in a country like Australia. A good diet and importantly plenty of activity outdoors are just as important today as they were in Charles Dicken\’s time.