The government is considering action amid fears they are being abused by people with eating disorders.
A public inquiry into the scandal that left nearly 3,000 people dead is due to begin.
Cancer Research UK predicts excess weight will be linked to more cancers in women than tobacco in 25 years.
One woman says a potential donor turned out to be married and had undergone a vasectomy.
One teenage girl has to travel five hours to London to get treatment for anorexia due to a lack of Welsh services.