Growth in discount retailers Lidl and Aldi is being driven by millennials, whose spend on grocery shopping is rising three times faster than that of the overall population, according to Nielsen.

Millennial spend at Aldi increased 46% year-on-year (52 w/e 16 July 2016) – compared to a 19% increase across all Aldi shoppers. Millennial spend at Lidl rose 28% – nearly twice the rate across all shoppers (15%).

Historically, Asda has had the strongest appeal with millennials – especially millennial families who make 17.1% of their grocery spend to Asda, compared to 11.4% among the total population.

“Although millennials, particularly families, have historically over-indexed on shopping at Asda, they’re now driving the growth of the discounters,” said Mike Watkins, Nielsen’s UK head of retailer and business insight.

“However, it’s important not to think of millennials as one homogenous group. For example, they’ve also increased spend dramatically at Marks & Spencer, which has a large price difference to the discounters due a different product assortment.”

Although overall grocery spend in Britain rose 2.7% year-on-year, spend among households where a millennial (aged 16-35) was the main shopper grew 7.9% – ahead of the next fastest-growing spenders, households led by people aged 65+ (up 3%).

The average millennial household with children now spends an extra £210 annually on groceries compared to last year, while millennial households without kids spend £113 extra.

In October, food marketing agency Kindred revealed that baking has become more common among millennials.