The Council of Mortgage Lenders is warning that Cat standard mortgages may not be the most appropriate loan type for all borrowers.
The CML says it is important borrowers understand that a Cat standard mortgage is not a guarantee it is the most suitable loan to meet their needs and is not a substitute for taking advice.
The voluntary regulator says there is a danger that consumers will assume that "Cat mortgage equals good and a non-Cat equals bad.
CML director general Michael Coogan says: "The CML and lenders support proposals to make information for borrowers clearer and easier to understand so that they can make good mortgage buying decisions.
"But it is very important that consumers do not see Cat standard mortgages as the only desirable type of mortgage."