“I’m not interested in how many two for one offers you buy at the supermarket,” said the prime minister during her Tory conference speech, which was interrupted by climate protesters.
In an attack on “virtue signalling” policies, Ms Truss vowed: “I’m not going to tell you want to do, or what to think, or how to live your life.”
Ms Truss had vowed to scrap Mr Johnson’s plans to restrict “buy one get one free” (Bogof) offers and advertising of junk food if she became prime minister.
She said during her leadership campaign that proposed bans to multi-buy deals on unhealthy food and sugar and salt taxes would be thrown out, after Mr Johnson delayed moves during the cost of living crisis.
“Those taxes are over,” Ms Truss said previously. “Talking about whether or not somebody should buy a 2-for-1 offer? No. There is definitely enough of that.”
Doctors have condemned Ms Truss over her move to ditch junk food promotions as the NHS struggles with an obesity crisis, saying the retreat was “hugely disappointing”.
The British Medical Association (BMA) warned that “lives are at risk”, urging Ms Truss not to put “business profits before the health of our children”.
Ms Truss’s first conference as PM has been marred by bitter rows, with a U-turn over plans to axe the top rate of tax after a backbencher rebellion, and ministers urging her to boost benefits in line with inflation.
Referring to her U-turn on the top rate of tax, the prime minister told the conference hall: “I get it and I have listened,” but repeated her claim that the fuss caused by the rebellion had been a “distraction”.
She went on to attack Labour, the unions, climate activists and “Brexit deniers” as elements of an “anti-growth coalition” holding Britain back.
Asked if anti-junk food campaigner Jamie Oliver was in Ms Truss’s “anti-growth coalition”, the prime minister’s press secretary would not comment on individuals considered to be holding back growth.
Ms Truss tried to smooth over recent rows, after home secretary Suella Braverman expressed her frustration with the 45p tax rate U-turn and accused rebel MPs of staging a “coup”.
Meanwhile, Commons leader Penny Mordaunt broke collective responsibility by speaking out on the possibility of real-terms benefit cuts, while Welsh secretary Robert Buckland suggested he was also opposed to such cuts.
Foreign secretary James Cleverly denied infighting, and said voters who have deserted the Tories will return to the party after taking the “bitter-tasting medicine” of the Truss economic plan.
Mr Cleverly said the huge poll leads enjoyed by Labour were only a “blip” sparked by the radical nature of the prime minister’s borrowing-fuelling tax cut spree.