Macro Tracking on GLP-1 Medications (Ozempic, Wegovy, Mounjaro)

TL;DR

• GLP-1 drugs cut appetite hard, so the risk isn’t overeating; it’s eating too little of the right things and losing muscle alongside fat.
• Aim for 1.6-2.2 g of protein per kg of body weight, even when you barely feel like eating.
• Resistance training plus adequate protein is what keeps weight loss from becoming mostly muscle loss.
• Track macros not calories obsessively: on a suppressed appetite, a calorie deficit usually takes care of itself.
• Smaller, protein-first meals and electrolytes manage the most common side effects (nausea, fatigue, constipation).

Why tracking changes on a GLP-1

GLP-1 receptor agonists like semaglutide (Ozempic, Wegovy) and tirzepatide (Mounjaro) work largely by slowing gastric emptying and blunting hunger. For most people the calorie deficit arrives on its own; you simply stop wanting to eat as much.

That flips the usual problem. On a standard diet, the hard part is not eating too much. On a GLP-1, the hard part is eating enough of what matters when food feels like a chore. If you let intake drift to whatever is easiest, you tend to under-eat protein and lose more lean mass than you should. This is the inverse of the struggle most people face, where the challenge is why you’re always hungry in a calorie deficit.

So the tracking job shifts. You are less worried about staying under a calorie ceiling and more worried about hitting a protein floor every single day.

What the research flags

Studies on GLP-1 weight loss consistently note that a meaningful share of the weight lost can be lean mass, often cited in the region of 25-40% of total loss depending on the trial and whether participants trained. That proportion drops when people resistance train and eat adequate protein. The medication shifts the scale; what you do with diet and training shapes the composition of that loss.

Protein is the non-negotiable

Set protein first, build the rest of the day around it. If you’re unsure where your number lands, our guide to how much protein you need per day walks through it.

A practical target is 1.6-2.2 g per kg of body weight. If you weigh 80 kg, that is roughly 128-176 g per day. On a heavily suppressed appetite that can feel impossible, which is exactly why you plan it rather than hope for it.

Protein-first meals

Eat the protein before anything else on the plate. When you fill up after a few bites, you want those bites to be chicken, eggs, fish, Greek yoghurt or tofu, not bread.

Lean on protein density

When volume is the enemy, density wins. A protein shake delivers 25-30 g in a glass you can sip slowly. Skyr or 0% Greek yoghurt, cottage cheese, tinned tuna and chicken breast all pack protein into small portions. Log them and you’ll often find you can hit target across three small feeds rather than three full meals.

Don’t chase an aggressive deficit on top of the drug

The medication is already creating a deficit. Stacking a deliberately steep calorie cut on top is how people end up exhausted, losing muscle and stalling.

If you track and notice you’re eating 1,000 kcal a day without trying, that’s a signal to nudge intake up with protein and whole foods, not to celebrate the low number. Sustainable fat loss on a GLP-1 still tends to land around 0.5-1% of body weight per week. Faster than that, and you’re usually trading muscle for a number on the scale. And remember the scale lies for plenty of harmless reasons, as we cover in why the scale goes up in a calorie deficit.

Fibre and carbs still matter

Slowed digestion plus low food volume makes constipation common. Aim for 25-30 g of fibre from vegetables, fruit, legumes and wholegrains, and keep some carbohydrate in the diet for training energy and gut function. Cutting carbs to zero while nauseous is a recipe for fatigue.

Managing side effects with food

Nausea, reflux and early fullness are the usual complaints, especially after a dose increase. Tracking helps here too, because the patterns become visible.

• Smaller, more frequent meals. Four to five small feeds sit better than two or three large ones.
• Slow down. Delayed gastric emptying means the “I’m full” signal lags. Eat slowly and stop before you feel stuffed.
• Limit greasy and very large meals. High-fat, high-volume plates are the most common trigger for nausea on these drugs.
• Electrolytes and water. Reduced intake can mean low sodium and dehydration, which feel like fatigue. Salt your food and keep fluids up; our note on sodium and electrolytes for macro trackers explains why this matters more than people think.

Use your log to spot trouble

If your tracking shows several days under 1,200 kcal with protein well below target, or you’re skipping meals entirely because nothing appeals, that’s worth raising with your prescriber. The app’s job is to make those trends obvious before they cost you energy and muscle.

Train to keep what you’re paying for

Diet protects muscle; training is what tells the body to keep it. Two to three resistance sessions a week, working the major muscle groups, is the single biggest lever for ensuring the weight you lose is fat rather than the muscle you’ll want back later. If you’re over 40, the adjustments in macro tracking for beginners over 40 are worth a read alongside this.

You don’t need a complicated programme. Squats, hinges, presses, rows and some carries, progressed gradually, paired with enough protein, will do the job alongside the medication.

How Chowdown fits

When appetite is low, you want logging to be near-frictionless or you simply won’t do it. Snap a photo of the meal and let the AI estimate it, scan a barcode for your shake or yoghurt, and watch your protein total climb through the day so you know whether you still owe yourself 40 g before bed.

Set protein as the macro you actually care about, leave calories as the secondary number, and let the deficit the medication creates do its work while you defend your muscle. That’s the whole game on a GLP-1: lose fat, keep strength, feel human while you do it.

This is general information, not medical advice. Always follow the guidance of the clinician who prescribed your medication.