Quick Navigation
There's no official Mounjaro diet, and that's a good thing
Mounjaro is tirzepatide, a medicine licensed in the UK to be taken alongside a reduced-calorie diet and regular movement. The medicine handles the appetite. You still have to point the fork in the right direction.
It works by slowing how quickly your stomach empties and turning down the volume on food noise. You feel full sooner and stay full longer. In the SURMOUNT-1 trial, people on the highest dose lost up to 20.9% of their body weight over 72 weeks.
Here's the bit nobody selling you a 'Mounjaro meal plan' wants to admit. The plan isn't secret. It's the same sensible eating a dietitian would have given you for free, only now the medicine makes it easier to actually stick to.
Protein first is the rule that actually moves the needle
Muscle is the one thing Mounjaro can't protect for you. Lose weight too fast without enough protein and a good chunk of what comes off is muscle, not fat. That's why protein first is the rule I repeat until I sound like a stuck record.
Aim for at least 0.8 grams of protein per kilogram of body weight a day, more if you train. For most people that's roughly a chicken breast, a fillet of fish, a tub of Greek yoghurt, and a handful of lentils spread across the day.
And here's the trick that actually helps on this medicine. Your appetite can vanish mid-meal, so eat the protein on your plate before the rice or potatoes. When the 'I'm full' switch flips, you've already had the important bit.
Some foods turn Mounjaro from helpful to unpleasant
Because your stomach empties more slowly, the foods that used to be 'a bit heavy' can now sit around long enough to cause proper trouble. Greasy takeaways, very spicy curries, and anything fizzy are the usual suspects for nausea and bloating.
Fizzy drinks get a special mention. The carbonation adds gas to a stomach that's already taking its time. (The burps alone are a public service announcement.)
You don't have to swear off them forever. In the first few weeks, while your body adjusts, keep meals small, bland, and low in fat. If nausea shows up, ginger tea and cold foods like yoghurt tend to be gentler than a hot, heavy plate.
Constipation is the other one that catches people out. Get ahead of it with fibre, plenty of water, and magnesium if you need it, from day one rather than waiting until it's a problem. The full list of what's normal and what isn't is in my guide to slimming injection side effects.
A week of eating that won't make you miserable
A patient of mine with type 2 diabetes lost about a quarter of his body weight over nine months on Mounjaro. His plan wasn't punishing. It was a high-fibre, mostly plant-based diet and a few walks. No marathons, no cabbage, no daily hour on the treadmill.
A day of it looks roughly like this. Greek yoghurt with berries and chia seeds for breakfast, a grilled chicken salad at lunch, baked salmon with greens in the evening. Snacks are a boiled egg, cottage cheese with apple, or a small handful of nuts.
The practical stuff matters more than the fancy stuff. Batch-cook a few protein bases on a Sunday. Serve the same family dinner with extra chicken and fewer potatoes. And remember your appetite is lowest a day or two after the injection, so eat small then and a bit more later in the week.
This plan isn't for everyone, and that's worth saying
Mounjaro is prescribed for adults with a BMI of 30 or above, or 27 and above with a weight-related condition like high blood pressure or type 2 diabetes. If you don't meet that, a decent clinic tells you so rather than taking your money.
It's also off the table if you're pregnant or breastfeeding, or if you've had pancreatitis or a certain type of thyroid cancer. A proper online assessment catches all of that before a single pen leaves the pharmacy.
The rule of thumb once you're on it: if you can't keep food down for more than a couple of days, or you're getting severely dehydrated, get in touch with your prescriber. Not everything is fixed with a bigger glass of water and good intentions.
Cost-wise, Mounjaro starts at £174.99 a month, with the assessment, prescription, and cold-chain delivery all included. No hidden fee at checkout, which shouldn't be a selling point but somehow is.
