In short
Portions on these medications are smaller than most people expect, and the practical problem is not deciding how much to cook but what to do with what you do.
By Alsen Walker · Updated September 20, 2026
Portions on these medications are smaller than most people expect, and the practical problem is not deciding how much to cook but what to do with what you do not eat. Serving less and going back works better than serving normally and leaving food, both for waste and for how it feels.
Smaller portions are expected. Eating almost nothing is not, and if most meals are going uneaten that is worth telling your prescriber rather than adjusting around indefinitely.
For how this fits alongside the rest of eating and training on a GLP-1, see Eating and Training on a GLP-1: The Complete Guide.
Serve less, return if you want more
The single most useful habit. A smaller plate that you finish beats a normal plate you abandon, and the second one leaves you looking at food you cannot face.
Around half what you would previously have served is a reasonable starting point. Adjust from there rather than from a rule.
Protein first, every time
Fullness arrives early and without warning. Whatever you eat first is what you actually get, so the protein should not be the thing you save for later.
This matters more here than any other portion advice, because protein is what protects muscle and it is the first thing to fall.
Cooking for one
Batch cooking works well if you portion it small. Freeze in single servings rather than family-sized containers, so a bad day does not mean defrosting more than you can face.
Foods that keep well and need no cooking earn their place: yoghurt, cottage cheese, tinned fish, pre-cooked chicken, eggs boiled in advance.
Buy smaller quantities of fresh food than you used to. A shopping habit built around your old appetite produces waste and guilt in equal measure.
Leftovers, safely
Splitting one meal across two or three sittings becomes normal, which makes storage more relevant than it used to be.
Cool leftovers quickly, refrigerate promptly rather than leaving food out, and reheat thoroughly. Do not keep things indefinitely on the basis that you are eating small amounts.
If you are unsure, throw it out. The cost of wasted food is lower than the cost of a stomach upset on a medication that already makes you queasy.
Restaurants and other people’s cooking
Ask for a box when the food arrives rather than at the end. It removes both the decision and the plate-watching.
With a host, saying plainly that the food was good and your appetite is small usually settles the awkwardness. A half-eaten plate reads as a judgement on the cooking unless you say otherwise.
The waste guilt
Worth naming, because it bothers people more than they expect. Smaller shopping, smaller serving, and freezing in single portions address most of it.
Finishing food you do not want in order to avoid waste is a poor trade on these medications, and it usually results in an uncomfortable hour rather than a virtuous one.
Serve less and go back rather than serving normally and leaving food. Restaurants have their own version of this, covered in eating out on a GLP-1, and if most meals go uneaten, that is worth reporting.
Frequently asked questions
How small should portions be?
Smaller than before, varying by person and day. Serve less and return rather than working to a fixed amount.
Is it normal to eat a few mouthfuls?
Common on difficult days. Consistently, across days, is worth reporting.
Should I still eat three meals?
Several smaller ones often works better than three you cannot finish.
How long do leftovers keep?
Follow standard food safety guidance rather than extending it because portions are small.
What if I cannot finish a protein shake?
Sip it over an hour. It does not have to be one sitting.
Am I eating too little?
If you feel persistently cold, exhausted, or are shedding hair, probably yes. Speak to your prescriber.
Sources and further reading
- National Institute of Diabetes and Digestive and Kidney Diseases (NIH). Treatment for overweight and obesity. www.niddk.nih.gov
- MedlinePlus (US National Library of Medicine). Semaglutide injection: drug information. medlineplus.gov
- MedlinePlus (US National Library of Medicine). Tirzepatide injection: drug information. medlineplus.gov
- National Institute of Diabetes and Digestive and Kidney Diseases (NIH). Prescription medications to treat overweight and obesity. www.niddk.nih.gov
GLP1Hub content is for general information and is not medical advice. Prices and coverage rules change often, so confirm current details with the provider, your insurer and your prescriber. See our editorial standards and medical disclaimer.
