There has recently been a considerable amount of attention around GLP-1 medications like Mounjaro (tirzepatide). These drugs are changing the conversation around weight loss and offering hope to many people who have struggled to manage their weight for years.
As a nutritionist I want to share my perspective on how GLP-1s could, in some cases, fit into a more sustainable approach to weight loss.
What is Mounjaro?
Mounjaro is a weekly injection that mimics two key hormones in the body - GLP-1 (glucagon-like peptide-1) and GIP (glucose-dependent insulinotropic polypeptide).
The body has multiple receptors for GLP-1 in tissue such as muscles, bones and adipose and also in organs including the gastrointestinal tract, pancreas, kidneys, lungs, heart and brain.
In relation to weight loss, when used as prescribed, Mounjaro slows stomach emptying, improves insulin sensitivity and reduces appetite.
The result for many people is they have fewer blood sugar spikes and less ‘food noise’ which allows them to more easily reduce their calorie intake and lose weight.
Why It’s So Effective
Mounjaro doesn’t rely on willpower. It changes the underlying biology that drives hunger and cravings. For people who have tried every diet under the sun, this can feel like a revelation.
However - while Mounjaro is powerful, it’s not a magic fix.
A Tool, Not a Shortcut
My view is that Mounjaro can be a useful tool - particularly for individuals who have significant weight-related health issues.
If you’ve been struggling with your weight for several years it may create the space for change: less hunger, more focus and perhaps a sense of momentum.
But a GLP-1 alone won’t teach someone how to nourish their body, how to regulate stress or how to support long-term metabolic health.
It doesn’t build healthy habits, address emotional eating, or ensure you’re getting the right balance of nutrients — all of which matter just as much for sustainable results.
The reality is that many people regain weight once they stop the medication, especially if they haven’t addressed the underlying lifestyle and dietary patterns that contributed to the gain in the first place.
Why Nutrition Still Matters
One of the most common things I see with clients using Mounjaro is a dramatic drop in appetite. While that’s part of how the drug works, it also means that food intake can become so low that the body isn’t getting the essential nutrients it needs.
Over time, this can create new issues such as fatigue, low mood, digestive sluggishness or even hair thinning. These can all be signs that the body isn’t being properly nourished.
When you’re eating less the quality of the diet becomes even more important.
It’s not just about calories - it’s about the composition of those calories.
Are you getting enough protein to prevent muscle loss?
Are you eating foods that support your gut health and liver function?
Is your intake of essential fats, magnesium, B vitamins and iron sufficient for energy, hormonal balance and brain health?
If you’re currently taking GLP-1 medication and unsure what to eat day-to-day, you can find more structured guidance here:
GLP-1 Nutrition Support: What to Eat on Mounjaro, Wegovy & Ozempic
Without proper nutritional guidance, it’s easy for meals to become minimal, repetitive, or heavily processed especially when appetite is low and cooking feels like a chore.
Lack of nutrients can have unintended consequences, especially during long-term use of GLP-1 medications. In some cases, clients develop muscle loss (sarcopenia) or worsen metabolic health despite the weight loss on the scales because what’s being lost isn’t just fat.
This is where nutrition plays a crucial role. For example:
Protein intake needs to be consistent and adequate, ideally spread across meals, to help preserve lean body mass.
Fibre-rich foods help maintain digestive regularity, which can be disrupted by GLP-1 medications.
Micronutrient density matters more than ever — a small plate of food still needs to deliver the key vitamins and minerals your body relies on daily.
Hydration and electrolyte balance can be impacted, particularly with reduced food volume or when nausea is a side effect.
There’s also a psychological aspect. Appetite suppression can sometimes disconnect people from their natural hunger cues or lead to erratic eating patterns, including long periods of under-eating followed by episodes of emotional eating or snacking.
Structure and personalised advice can help rebuild that connection to food in a more intuitive and supportive way.
Ultimately, the goal isn’t just weight loss - it’s healthy, sustainable weight loss with energy, mood, digestion, sleep and hormone balance all in balance. That only happens when nutrition is thoughtfully tailored to the individual.
Why Medical Oversight Is Essential
GLP-1 medications like Mounjaro are not appropriate for everyone, and they should never be used without input from a qualified prescribing doctor. These are powerful drugs that affect multiple systems in the body including blood sugar regulation, digestion and cardiovascular function.
Medical oversight is essential to assess whether a GLP-1 is suitable and to monitor for side effects such as nausea, constipation, gallbladder issues or in rare cases, more serious complications.
A healthcare professional will also consider how the drug interacts with any existing conditions or medications you may be taking. For example, those with a history of disordered eating, gastrointestinal disease or thyroid issues may need additional support or a different approach.
Monitoring by a doctor ensures the safest and most effective use of GLP1. It also provides a structure for reviewing progress, adjusting dosage and deciding when and how to taper or stop the medication if appropriate. This is not something to self-manage or source without guidance.
If you’re considering starting Mounjaro, or you’re already taking it, make sure you have a prescribing doctor who is actively involved in your care.
Final Thoughts
GLP1 medications are changing the landscape of weight management. They offer an important new option particularly for those who’ve been let down by traditional advice or struggled due to hormonal or metabolic challenges.
However they work best as part of a bigger picture. I believe that the most effective, long-lasting results come when medication is combined with medical support, personalised nutrition, realistic lifestyle changes and a compassionate, practical approach to health.
Mounjaro is not a standalone solution — but in some cases it can be a helpful starting point.
If you're currently using a GLP-1 like Mounjaro under the care of a prescribing doctor and want to make sure your nutrition is supporting your health and goals, please get in touch. I offer personalised nutrition advice to help you optimise results, maintain energy, and avoid common nutrient pitfalls.
I also have a FREE download that contains nutrition tips for before, during and after using the medication - CLICK HERE