The survey comes amid moves by fast food giants to deflect claims that they contribute to the growing obesity problem by introducing "healthier" menu items and scaling back their advertising to children.
The Which? survey investigated the big four chains, Burger King, McDonald's, KFC and Pizza Hut. It accused them all of still offering foods high in fat and salt and also found that they carried inaccurate nutritional information on their websites.
The report said three of the salads offered by McDonald's and KFC had more salt than any other options on the menu -- including burgers and fries. Particular offenders include the KFC Original Chicken salad, which has more salt than a chicken fillet burger and fries; and the Zinger Crunch Salad, which has 7.7g of fat per 100g.
McDonald's is criticised over its Crispy Chicken Ranch salad with dressing, which the survey said contained half the saturated fat level recommended for a woman's daily intake.
All four were found to have inaccurate information on their websites. Which? found that the Burger King Whopper and regular fries contained 19g of saturated fat, compared with the 13g stated on the website. KFC was also founded to have slimmed down the level of fat contained in its Zinger Crunch salad on its website, while McDonald's shaved more than 100 calories off a Big Mac and medium fries.
The research follows a survey produced by the the health group Consensus Action on Salt and Health, which campaigns for health warnings on food. Published in July, it found that one in five ready-made salads from high street stores and fast-food outlets contained the same amount or more salt than a Big Mac and fries.
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