In Mexico, stem cell treatment is attracting attention from the north.

The clinics that perform the treatment inject patients with stem cells that can replace damaged tissues, help stroke victims to recover, and even help some blind people to see.

However, there are concerns about a lack of regulatory oversight from the government. 

The clinics claim they are doing clinical trials, and testimonials from patients can be found on their websites.

Academic researchers say stem cell therapy has promise. But they are cautious in conducting clinical trials because cells can mutate and produce tumours.

TRT World'sAlasdair Baverstock has more.