Personal care is the most popular sector in the non-food market, with 44.2% of shoppers choosing to buy these products in the supermarket, a rise of 12.5 percentage points in five years.
This is followed by homewares with 20.4% of shoppers buying from supermarkets, a rise of 10.7 percentage points, and clothing with 20.3%, a rise of 8.9 percentage points.
Music and video products are bought regularly by 19.9% of consumers, a rise of 5.4 percentage points, and electrical items by 11.4% of consumers, a rise of 6.6 percentage points.
All in all supermarkets control £19.7bn (11%) of the £177bn UK non-food market, putting pressure on the specialist stores.
Asda has become the fifth-largest clothing retailer in the UK, with Tesco not far behind in ninth place; both stores now have more regular customers than BHS, Gap and H&M.
Neil Saunders, Verdict's director of consulting, explains why: "What the grocers offer is convenience with very competitive prices. For the time pressed, cost conscious customers it is a great advantage to be able to pick up good priced clothing or electrical items at the same time as doing a food shop.
"Almost everyone has to go grocery shopping and that means the grocers have a huge base of customers who regularly visit their stores. That's an enormous advantage because it allows them to easily put non-food ranges in front of those customers."
Saunders predicts that these figures will continue to rise with the increasing popularity of internet shopping: "Today's supermarkets are no longer simple grocers, they are cathedrals of consumption, the department stores of the modern age.
"We expect them to build on this position over the next few years and that will certainly make life difficult for other specialist players."
