Which? reveals shrinking products costing us more - from Andrex Puppies, McVitie's, and Dettol to Sensodyne
You may not have noticed, but going to the loo in your own house has become more expensive.
That's because the UK's leading toilet roll manufacturer has been caught shortening some of its best-selling products.
Indeed, new research from Which? reveals that although a standard four-pack roll of Andrex has shrunk by 8% from 240 to 221 sheets, the price has not, with customers still paying an average of £2.
Similarly, the company's Puppies on a Roll brand, that used to have 221 sheets per roll, now has 190 - or 14% less than in 2006, according to the consumer watchdog.
But toilet roll is just one of a range of items Which? found had become smaller, with prices remaining the same - or, in some cases, increasing.
Other notable examples of shrinking groceries and toiletries include coffee, toothpaste, biscuits, bathroom wipes and orange juice.
Which? discovered that McVitie's dark chocolate digestive biscuits had shrunk by 10% from 332g to 300g, but the price in Tesco had risen by 10p to £1.69.
It also found that Dettol's pure bathroom wipes saw an 11% reduction from 36 to 32 wipes, however the cost of the product rose by 3p to £2.03 in one supermarket after the change.
One of the biggest downsizing manoeuvres was in tubes of Sensodyne's total care extra fresh toothpaste, which shrank by 25% from 100ml to 75ml.
The consumer watchdog also found that Tesco had the toothpaste on offer at "£2.40, was £3.60" before the product was reduced in size, but then the price soared to £3.49 after downsizing, making it more expensive per 100ml.
Richard Headland, the editor of Which? magazine, said its aim was to demand better transparency for consumers from retailers.
"Shrinking products can be a sneaky way of increasing prices," he said.
"We want manufacturers and supermarkets to be upfront about shrinking products so consumers aren't misled."
Over three-quarters of Which? members said they believed it was wrong for retailers not to highlight when products were reduced in size, but continued to be sold at the same price.
Which? said that when it contacted the brands following its research the majority of them said that pricing was a matter for the supermarkets.
The consumer group added that the manufacturers refused to disclose whether they had charged the supermarkets a lower wholesale price for their smaller products.
Kimberly-Clark, the American company that owns the Andrex brand, said its focus was "on meeting and exceeding the needs of consumers".
"Before the sheet count change we invested significantly in improving our product strength and softness," said a spokesman.
"Reducing the roll by a very small number of sheets helped make this multi-year, multi-million pound investment in product quality possible."
Experts said that suppliers tended to cut sizes because they were under pressure to maintain profits to keep shareholders happy and believe, given the choice, customers prefer smaller products to price increases.