More than 200 food businesses in Tower Hamlets risk losing more than half of their customers after achieving a poor hygiene rating.
Research conducted by Checkit showed that 61% of restaurant-goers would not eat at an establishment that had a Food Standards Agency rating of two or below out of five.
In Tower Hamlets, that would mean 257, or 14%, of businesses, would lose customers. The figure is 31%, or 272, of Newham companies.
This compares with the 6% that would be affected in Greenwich, which adds up to 64 out of the 1,034 in the area.
Checkit marketing director Dee Roche said: “Food hygiene is now the number one priority for consumers when eating out, meaning our research should act as a wake up call for those restaurants in London with poor food hygiene ratings.
“As well as the health of their customers they are risking the survival of their business – few of them could cope with 61% of diners boycotting their restaurant.
“These findings show why food safety is priority – customers rate hygiene as the number one reason, above service or rude staff when it comes to choosing whether to return to a restaurant.”
Checkit’s consumer research also found that diners would rather put up with poor service from rude and unhelpful staff than eat at dirty restaurants.
Two thirds of respondents rated unclean or dirty premises as the first or second reason for not returning to a restaurant.
Around 16% cited slow or poor service with 32% saying rude or unhelpful staff would stop them coming back again.