For that week, all I was allowed to ingest was the cloudy water from a coconut. A strange taste, not sweet and not bitter; not much of anything. I was given two glasses of it per day: one in the morning and one in the late afternoon. I’d file into the dining room with a few other residents, all of us silent in the loose white linen clothes Dr Bellavit provided: plain shifts like nightdresses, for both women and men. I looked for Tilly, but she was never there at the same time I was.

When the hunger began, I read from Dr Bellavit’s book. You will experience what feels like hunger. This sensation may be unpleasant, even uncomfortable. Yet it is imperative that you do not accede to your baser instincts. You must expel their force from your body to let the healing begin.

I did what she suggested and undertook positive visualisation exercises, imagining myself pulling in clean air and expelling poison with each breath.

But it didn’t take long for my mouth to dry out and my stomach to grow hollow. I began to see everything in terms of what was wet and what was dry, what was edible and what was not. These boundaries grew less and less distinct. On the evening of the fifth day, I looked at the damp towel in my bathroom and wondered whether it would be cheating to twist its contents into my mouth. When I saw Dr Bellavit, I noticed how much her head, with its broad forehead and tiny, receding chin, resembled an egg. I could not focus on what she was saying for thinking about tapping a spoon against it, and salting the rich yellow yolk within.

‘This is normal,’ said the egg, nodding deliciously at me. ‘This is good.’

By then I knew what the strange chair in the bathroom was for. It had become part of the structure of my days.

In the morning there was the white juice of the coconut, followed by cleansing. When Dr Bellavit first appeared in my room carrying a hose and a bag, I said, ‘What’s that?’

She locked the door.

It was to scrub away the toxins, she explained. They had adhered to the walls of my bowel; they were corroding me like rust. ‘Our line of attack must be direct,’ she said.

And every afternoon, I received a massage. ‘The poison is in the fibres of your muscles,’ Dr Bellavit said. ‘It lives in the fascia, encasing them; it is all through your organs.’

I would lie on my bed and clamp my eyes shut as her hands came down on my back in fists. Each time they connected she chanted, ‘Expel, expel, expel.’

Afterwards she held me as though I were a child, and let me cry. Often she didn’t leave the room until I was asleep.