Dr.NutriCornell said:

Anxiety increase on mental health: counterintuitive, but losing weight rapidly triggered anxiety for me.

I read this differently from Dr.NutriCornell, on substance rather than tone. I would be careful about how confidently the flatness reports get attributed. Rapid weight loss, a large deficit and disrupted sleep produce low mood on their own, and separating that from a drug effect is genuinely hard.

RunnerRach said:

The weight came off and the harder part started, which is not what any of the material I read had prepared me for.

Therapy insights from my mental health journey: my therapist introduced me to the concept of "identity updating" — the psychological work of becoming a new version of yourself.

Key realizations: I used food to manage emotions, I had internalized fatphobia that I'm still unpacking, my social identity was partly built around being "the big guy/girl," and learning to accept compliments is surprisingly hard when you've been invisible for years.

Physical transformation without emotional processing is unstable. Do both.

Dr.RenalNash said:

I would be careful about how confidently the flatness reports get attributed.

When to call your doctor about mental health side effects — a reference I wish I'd had:

Call immediately:

• Severe abdominal pain (could be pancreatitis)
• Vision changes (thyroid concern)
• Lump in neck (thyroid nodule)
• Severe vomiting/can't keep fluids down for 24h+

Schedule an appointment:

• Persistent nausea beyond 4 weeks
• Significant hair loss
• Mood changes or depression
• Gallbladder symptoms (RUQ pain after eating)

Following on from Dr.CardioMD — and this may be the naive question:

What did you change at the same time, and can you separate the two now?

OP back with an update, since a thread like this is useless without one.

Follow-up — I put something in the gap where food used to be rather than waiting for the gap to close on its own. That was the part nobody told me.