Scientists have discovered a gelling agent found in jelly may slow tumour growth – but do not recommend giving up fruit and vegetables just yet.

Pectin, which is used in jams and jellies, binds the protein in tumour cells that grow and spread throughout the body.

A research team in the US found the substance had previously been shown to kill or prevent the spread of cancer in a test tube, Reuters reported.

But the full extent of how pectin can protect against cancer remains is and how the body takes in the "bioactive fragments", so lead researcher Patrick Gunning advises not to start eating more of the condiments.

He said: "Given what we know from our study and the others, we feel that the best advice is to eat plenty of fruit and vegetables in the likelihood that it will supply bioactive fragments from the pectins."

Research was published in the Federation of American Societies for Experimental Biology Journal, which includes work from independent members.