In the United States, prescription drugs, for any illness, can be advertised on television directly to patients. While the ads have to include lots of technical information on side effects and contraindications, they are still all over the airwaves. The same is not true in Great Britain. No drugs can be advertised on television or in any manner that is direct to the consumer. They can, of course, be marketed to physicians. More specifically, British law addresses cancer treatments, singling out any products or substances that reference a benefit for cancer
The issue came up recently when a British television star, Noel Edmonds, credited an Electromagnetic Yoga mat for curing his cancer. While the field of electromagnetic treatments for cancer is new and could be promising, no research to date can show that it is a cure for cancer. Immediately, the makers of the EMPpad disavowed any connections to Edmonds, putting a statement on the top of their website that they don't agree with his claims and vehemently assert that there is no evidence of any affect the pad has on cancer. They were likely concerned about the laws concerning cancer adverts and anxious to let consumers know that this endorsement had not come from them.
While in the US makers of supplements not subject to the FDA regulations might tout any and all kinds of benefits, including cancer fighting abilities, in the UK they are quite strict about who can say what about cures for cancer, leaving it to the medical professionals to sort out.