Residents are advised to make sure any Christmas treats and other food they buy is purchased from a business registered to sell food, even if it is a small operation they see on Facebook.
West Lancashire Borough Council wants people to be careful as it is aware of a trend in small food operators increasingly advertising their services on Facebook and other social media.
A number of these are selling Christmas cakes and other festive party food.
Councillor Kevin Wright, portfolio holder for Health and Community Safety, said: "Any person or business that sells food to the public on a regular basis must be registered with the Council, even if they are an individual making food in their kitchen at home to sell. This is so they can be checked to make sure they are complying with food hygiene regulations and, where appropriate, given a food hygiene rating.
"Whilst we would advise residents to check if any food business is registered for their own peace of mind, the Council wants to support legitimate local business and I would strongly recommend anyone thinking of operating a food business to contact the Council's Food Safety team for advice."
People can check if a business they buy food from is registered and inspected by visiting Food Standards Agency (external link).
Any one selling food to the public should register with the Council 28 days before they open for business. More information, including how to register a food business, can be found at food safety.