The Man Who Ate Everything (BBC Four, Wednesday 11.45pm) sounded like one of those tumour-porn medical shock-docs you used to get only on Five but now air constantly on most channels at most times of the day.

In fact it wasn't a touchingly exploitative portrait of the world's most distended gastric canal but a tender eulogy for legendary food writer Alan Davidson 'legendary' here meaning 'some people who shop at Waitrose have heard of him'.

He spent 20 years penning the Oxford Companion to Food, an encyclopaedia "from aardvark to zucchini" of everything even vaguely edible. Andrew Graham-Dixon hosted this warm portrait of a man passionate about what he did and his enthusiasm was more infectious than an ebola omelette.

We met eager belt-looseners at the Oxford Food Symposium, a community of eccentric foodies who gather to swap tales about obscure creatures they've digested and, you suspect, to see who's put on the most weight since last year.

Famous fans included Raymond Blanc, to whom Graham-Dixon put forward the view that Davidson was "a man who kept things alive that otherwise might have been forgotten". That's unlikely, though, with Davidson a keen believer that anything breathing should be shoved into a blender before it scampers back into the bushes.

Some regard his book as "the Bible of fusion cuisine" but for others it's far bigger than that. TV impresario John Lloyd hailed his opus as "the greatest book in the English language" seems like Shakespeare could have done with more references to canned meat.

Between lengthy treatises on the origins of Spam and the socio-political implications of eating sheeps eyes, Davidson advocated a curiously gastro-centric view of evolution. Yet you'd think creatures that biologically strive to be delicious wouldn't survive long in the wild.

Still, this portrait of an omnivore in the most literal sense was both charming and compelling even if the great man's great book is really more Spamlet than Hamlet. (To eat or not to eat that is the question.)

Oh, and as for aardvark apparently it tastes like pork. Much like everything else.

More from this column