With each Briton getting through an average of 50 toilet rolls a year, the carbon footprint created by supplying it is huge.
Makers including Andrex have made rolls last longer by increasing sheet numbers.
But Sainsbury's is set to try something new: shrinking the inner tube.
The move, believed to be a UK first, should avoid 500 annual lorry trips from suppliers to stores.
And the supermarket insists customers will not struggle to squeeze the new roll on to holders.
The diameter of the roll will fall from 123mm to 112mm, with the number of sheets still 240.
The new rolls will be on sale in May at the same price as before – £1.99 for four. »