Singapore's Society for Men's Health and a pharmaceutical firm are proposing a four-point scale for erectile dysfunction, allowing men to rate their own hardness with four categories: cucumber, unpeeled banana, peeled banana and tofu (bean curd).

"Men should aim for this," UK sex therapist Victoria Lehmann told a news conference, holding a cucumber.

The scale does not involve any scientific measurement -- patients would merely be asked to assess their own levels of hardness -- and has not been accepted by any medical authorities.