Alexia Zimmerman went through GLP-1 treatment herself. The book she wanted as a patient, one that answered questions in plain language, was honest about trade-offs, and showed its sources, did not exist. So she spent a year in the research and wrote it.
She is not a doctor and does not write as one. She writes as the person on the other side of the prescription pad: the one deciding whether to start, noticing what changes, and wondering what happens after stopping. Every claim in her books is cited, so you can read what she read and decide for yourself.