The consistent triumph of good over evil in fantasy literature may be linked to villains' aversion to sunlight, researchers have suggested.

According to the theory, evildoers who dwell in the darkness and eat a poor diet are left lacking in vitamin D, leading to muscle weakness and critically undermining their performance in battle.

The idea is proposed by Dr Nicholas Hopkinson of Imperial College London and his son Joseph, 15, in the Christmas edition of the Medical Journal of Australia.

No previous studies have investigated vitamin D levels in imaginary populations, so to test their hypothesis, they scoured J.R.R. Tolkien's The Hobbit for references to characters' living conditions, habits and diet. They used these clues to give each protagonist a score rating their likely vitamin D levels.

Vitamin D is produced in the skin when it is exposed to ultraviolet light, and can also be obtained from some foods such as oily fish, egg yolks and cheese.

The Hobbit's hero, Bilbo Baggins, lives in a hole, but it has windows, and he is known to enjoy sitting in the sun overlooking his garden. The hobbit diet is clearly varied, as he is able to offer cake, tea, seed cake, ale, porter, red wine, raspberry jam, mince pies, cheese, pork pie, salad, cold chicken, pickles and apple tart to the dwarves who visit to engage him on the business of burglary.

In contrast, villains such as Gollum, the goblins and Smaug the dragon spend most of their time in darkness.

The good characters, who all emerge victorious, have significantly higher vitamin D scores than the bad characters, who are defeated.

“Systematic textual analysis of The Hobbit supports our initial hypothesis that the triumph of good over evil may be assisted to some extent by the poor diet and lack of sunlight experienced by the evil characters,” the researchers conclude.

They acknowledged that their study had several limitations. “We have not discriminated between creatures that can be considered, broadly speaking, to be mammalian and those that are not and whose physiology is more obscure.

“Unfortunately, the principal purpose of the author of The Hobbit was not to provide a systematic dietary history, so reporting bias is a possibility. In particular, there is an emphasis in the text on meat items similar to Homer’s Odyssey, where feasting is a recurrent motif but where few references to salad are made.

“More research would be needed to establish whether the results of the current pilot investigation are representative of the wider Tolkien corpus and indeed of fantastic literature in general, although this will need to be balanced against the problems of proportionality of effort.

“Well-constructed randomised controlled intervention studies may need to be imagined,” they add.

Reference

J.A. Hopkinson and N.S. Hopkinson. ‘The Hobbit – an unexpected deficiency.’ Medical Journal of Australia, 16 December 2013. doi: 10.5694/mja13.10218