hormones

Many American farmers use growth hormones as a standard part of their beef production, something that was banned in the UK and the European Union in the 1980s.

The runner’s high — which can occur with any form of exercise — was originally thought to be caused by the release of feel-good hormones called endorphins after a high intensity workout.

Possible treatments include chemotherapy, radiotherapy and drugs that help to stop the cancer growing - either by blocking hormones, boosting the body's immune system or targeting what makes cancer cells grow.

“That’s how they greet,” Ebsen told me a few weeks before, “their whiskers send signals straight up to their brain which tells them all about your smell, your hormones, everything.”

Dolphins are only rehabilitated if they’re endangered species; they tend to experience intense stress hormones and trouble breathing when they’re around people and out of the water.