If your doctor has prescribed a GLP-1 medication and you are about to start, a little preparation can make the first weeks easier. This guide is about the food side: what to ask your prescriber, what to expect from a changing appetite, how to set up your kitchen and routine, and how to look after your relationship with food. It does not cover whether the medication is right for you. That is a decision for you and your doctor, and this guide is written to sit alongside it.
At a glance, before you start
- Whether to start is a decision for you and your prescriber. This guide covers the food side.
- Tell your prescriber about any history of disordered eating, and about all your other medicines and supplements.
- Appetite changes and gut side effects are most noticeable when treatment starts and when it is stepped up, and they often ease.
- A regular eating rhythm and easy protein foods already in place make a smaller appetite simpler to manage.
- Dietitians Australia recommends nutrition support before, during and after treatment.
Questions to take to your prescriber
It is easy to leave the appointment with more questions than answers. A few that are worth asking:
- What side effects should I expect, how long do they usually last, and when should I call you?
- What should I do if I cannot eat or drink much on a given day?
- How will my other medicines be managed, especially any diabetes medicines, as I eat less?
- Do any tests make sense for me before or during treatment? (Routine screening is not recommended for everyone, but your doctor can tell you whether it applies to you.)
- When will we review how it is going, and what is the plan if we decide to stop?
- Can you refer me to a dietitian, and does anything make me eligible for a Medicare rebate?
On the last point, people with an eligible chronic condition can get up to five Medicare-subsidised allied health visits a year through a GP chronic condition management plan, shared across professions. Whether you qualify is your GP’s call. Private health cover may also include dietetics, and you can book a dietitian without a referral.
What to expect in the first weeks
These medicines slow how quickly your stomach empties, which is why you feel full sooner and for longer. Healthdirect lists nausea, vomiting and constipation among the common effects. Clinical guidance says gut effects are usually mild to moderate, happen mainly when treatment starts or is stepped up, and tend to ease, although constipation can last longer.
Experiences differ from person to person. If you feel nauseated, smaller and plainer meals, eating slowly and stopping when you are full usually help, and our guide to nausea and constipation on GLP-1 medication covers the food side in detail. Sipping fluids through the day matters too, because vomiting and diarrhoea make dehydration easier.
Getting your kitchen and routine ready
A smaller appetite makes planning more important, not less. A few things are easier to sort out before you start than once you are feeling flat:
| Area | What can help |
|---|---|
| Easy protein | Keep eggs, Greek yoghurt, cheese, tinned fish, tofu, lentils or beans and milk on hand, so a protein food is always the easy choice |
| Plain foods for rough days | Toast, crackers, rice, soup, yoghurt and plain chicken tend to be easier to manage when you feel unwell |
| Eating rhythm | Plan regular small eating times, because on a quiet appetite it is easy to drift into skipping meals |
| Fluids | Keep a water bottle where you will see it, and sip through the day |
| Fibre | Build up wholegrains, fruit, vegetables and legumes gradually, with plenty of fluid, to help with constipation |
| A simple food and symptom note | Jotting down what you ate and when you felt unwell for the first week or two shows patterns that are hard to see day to day |
| Movement | Starting gentle strength activity before treatment makes it easier to keep going (see protecting your muscle) |
| Social occasions | Think ahead about eating out and alcohol (see alcohol and GLP-1 medication) |
Our guide to what to eat on GLP-1 medication explains how to put protein first and eat well when you are barely hungry, and which nutrients can run low explains what to keep an eye on.
A consult before you start, or in the first weeks, can set this up around your own food, routine and health, so you are not working it out while you feel unwell. About the GLP-1 consult →
Looking after your relationship with food
A quieter appetite can feel like a relief. For some people it can also make it easier to slip into skipping meals or eating less and less, and it can bring up old worries about food or weight. Guidance for prescribers recommends considering screening for disordered eating before starting treatment, and Australian Prescriber notes that appetite suppression may lead to poor nutritional intake in people with eating disorders. If you have ever had an eating disorder, or are unsure whether your eating has been disordered, please tell your prescriber before you start.
Weight stigma matters too. A 2026 consensus statement points out that internalised weight bias can harm mental health. A weight-inclusive approach, which focuses on eating well, energy and health rather than only the number on the scales, is the way we work. If eating starts to feel like something to get through, or you notice the urge to restrict, Ausclin offers eating disorder support, and we will talk it through gently and without judgement.
Starting is not the end of the story
It helps to think about the whole course of treatment, including how you will look after your muscle and nutrients while on it, and what happens if you and your prescriber later decide to stop. Dietitians Australia recommends that people prescribed these medicines are supported with nutrition and lifestyle counselling before, during and after treatment, and our guide to stopping GLP-1 medication covers the later stage. Professional bodies recommend nutrition support, though trials of dietitian care alongside these medicines have not yet been done, so we describe it as something that may help rather than something proven.
When to talk to your doctor
Contact your doctor or seek medical advice promptly if you cannot keep fluids down, have ongoing vomiting with dizziness, confusion or unusual tiredness, or have signs of dehydration such as very dark urine or passing very little. Get urgent care for severe stomach pain that does not go away, especially if it spreads to your back. If you have diabetes, ask your doctor how your other medicines should be managed as you eat less. Do not change or stop your medication without talking to your prescriber.
Where a dietitian helps
A dietitian can help you set up your eating before you start, plan around likely side effects, and keep an eye on protein, nutrients and your relationship with food as treatment goes on.
Our GLP-1 medication support consult runs for 45 minutes, by telehealth or in person at Mount Hutton.
About the GLP-1 consult →Common questions
Is this guide about whether I should start a GLP-1 medication?
No. Whether a GLP-1 medication is right for you is a decision for you and your doctor. This guide covers the food and nutrition side for people who have already been prescribed one.
Should I see a dietitian before I start?
It can help. Dietitians Australia recommends nutrition support before, during and after treatment, and a plan in place before your appetite changes can make the first weeks easier. Trials of dietitian care alongside these medicines have not been done yet, so the recommendation rests on professional consensus. You can book without a referral.
Do I need to change what I eat before I start?
Not necessarily. Getting into a regular eating rhythm, stocking easy protein foods and keeping fluids up are the most useful things to have ready. You do not need a strict plan or to cut foods out.
What side effects should I expect?
Nausea, vomiting, diarrhoea and constipation are common, mostly when treatment starts or is stepped up, and they usually ease. Smaller, plainer meals and sipping fluids often help. Tell your prescriber if they are severe or not settling.
What if I have had an eating disorder?
Tell your prescriber before you start. Appetite suppression can make restrictive eating worse, and guidance recommends considering screening before treatment. Ausclin also offers eating disorder support.
Can I see a dietitian by telehealth?
Yes. Our GLP-1 medication support consult is available by telehealth from anywhere in Australia, or in person at Mount Hutton.
Where this comes from
General information only, not personal advice. Talk to your doctor or prescriber about your own treatment.
- Sievenpiper JL, Ard J, Blüher M, et al. Nutritional and lifestyle supportive care recommendations for management of obesity with GLP-1-based therapies. Obesity Pillars. 2026;17:100228. doi.org/10.1016/j.obpill.2025.100228
- Mozaffarian D, Agarwal M, Aggarwal M, et al. Nutritional priorities to support GLP-1 therapy for obesity: a joint advisory from the American College of Lifestyle Medicine, the American Society for Nutrition, the Obesity Medicine Association, and the Obesity Society. Obesity Pillars. 2025;15:100181. doi.org/10.1016/j.obpill.2025.100181
- Yates N, South T-L. Injectable drugs for weight management. Australian Prescriber. 2025;48(6):197-202. doi.org/10.18773/austprescr.2025.052
- healthdirect Australia. Weight loss medicine. Last reviewed March 2026. www.healthdirect.gov.au/weight-loss-medicine
- Wharton S, Davies M, Dicker D, et al. Managing the gastrointestinal side effects of GLP-1 receptor agonists in obesity: recommendations for clinical practice. Postgraduate Medicine. 2022;134(1):14-19. doi.org/10.1080/00325481.2021.2002616
- Dietitians Australia. Parliamentary Friends of Nutrition 2025: Nutrition first in GLP-1 care. 20 August 2025. dietitiansaustralia.org.au/advocacy-and-policy/parliamentary-friends-nutrition-2025-nutrition-first-glp-1-care
- Australian Government Department of Health. Medicare Benefits Schedule note MN.3.1: Chronic disease management – allied health individual services. www9.health.gov.au/mbs/fullDisplay.cfm?type=note&q=MN.3.1