A Functional Medicine approach to Mounjaro

This article will explore how Mounjaro works, who it might be best suited to, what to expect while taking it, and perhaps most importantly, how to lay the groundwork for long-term success whether you continue with it or not.

Introduction: Navigating the Mounjaro Journey with Clarity and Confidence

If you’ve recently started taking Mounjaro (tirzepatide), or are considering it, you may be feeling both hopeful and hesitant.

The stories of dramatic weight loss and metabolic improvements are everywhere. But so are the concerns about side effects, long-term safety, and what happens when you eventually come off it.

Maybe you’ve tried many things before, and this feels like your last resort. Or perhaps you’re wondering if relying on a medication means you’ve somehow failed. These are common thoughts, and it’s okay to have mixed feelings.

I want to be clear from the outset: this article is not here to tell you whether you should or should not take Mounjaro. That decision is deeply personal, and context is everything.

There are legitimate reasons both for and against using peptides like this, and they need to be considered carefully, perhaps with consultation with a professional that can guide that thought process.

While I do not prescribe peptide therapies, I regularly work with clients who are using Mounjaro and other peptides to support their weight loss, cardiometabolic health, muscle gain, injury recovery and more.

What I’ve found is that many people are given a powerful tool but little guidance on how to use it well, how to manage the side effects, or how to build the habits and physiological resilience that allow them to succeed not just during, but after treatment.

That’s where a functional medicine approach comes in. Rather than treating Mounjaro as a quick fix, we look at the bigger picture, your metabolism, gut health, hormones, nutrition, lifestyle, stress load, exercise, mindset and long-term goals.

What is Mounjaro and How Does it Work?

Mounjaro (tirzepatide) is a relatively new injectable medication developed for the treatment of type 2 diabetes and obesity.

Mounjaro (tirzepatide) works by mimicking two natural hormones in your gut that help regulate appetite, blood sugar, and insulin levels, GLP-1 and GIP. These hormones play essential roles in regulating appetite, blood sugar, and insulin function. By mimicking the effects of both GLP-1 and GIP, Mounjaro helps:

• Slow the emptying of food from the stomach, which increases satiety and reduces hunger
• Enhance insulin secretion in response to meals, improving blood sugar control
• Suppress glucagon (a hormone that raises blood sugar) when it is not needed
• Influence areas of the brain that regulate appetite and food cravings

These combined effects can lead to reduced food intake, management of food cravings and impulsive eating, more stable blood sugar, and for many, substantial fat loss over time.

In clinical trials, people using Mounjaro have achieved an average of 15 to 22 percent reduction in body weight, depending on the dose and duration of use.

Because of these impressive outcomes, Mounjaro is used not only for type 2 diabetes management, but also as a tool to address obesity, insulin resistance, and related cardiometabolic conditions like high blood pressure and fatty liver. These are areas that we specialist in supporting naturally through our functional medicine approach.

However, while its mechanisms sound straightforward, the real-world experience can vary greatly from one person to the next. It is not a magic solution, and without the right foundations in place, nutrition, movement, sleep, stress management, exercise, and gut health the results may plateau, or side effects may become harder to manage and there is a real risk of weight rebound, much like other very restrictive dieting strategies that do not address the root cause of why someone gained that weight in the first place.

Who is Mounjaro Best Suited To?

Mounjaro is typically prescribed to individuals with type 2 diabetes or those classified as obese, particularly when lifestyle changes alone have not delivered sufficient improvements in weight or metabolic health.

In recent years, it has also been used more broadly in people struggling with weight loss resistance, insulin resistance, or cardiometabolic conditions such as high cholesterol, high blood pressure, and non-alcoholic fatty liver disease.

That said, it is not suitable for everyone.

Mounjaro may be best suited to those who:

• Have a diagnosis of type 2 diabetes or prediabetes and need additional support for blood sugar control
• Have a BMI that categorises them as overweight or obese, especially with associated metabolic risk factors
• Have a history of yo-yo dieting or weight regain, despite ongoing efforts to improve lifestyle habits
• Struggle with appetite regulation, emotional eating, or intense food cravings
• Are under the care of a healthcare provider who can monitor their use and progress

It is important to stress that Mounjaro should not be seen as a replacement for foundational lifestyle change. It works best when paired with the right nutrition, exercise, and mindset strategies.

However, it may not be appropriate for those with a history of pancreatitis, certain thyroid conditions, or gastrointestinal issues such as gastroparesis. It is also not approved for use in individuals with type 1 diabetes or those who are pregnant or breastfeeding.

In my role as a functional medicine practitioner, I do not prescribe Mounjaro or other peptides, but I regularly work with clients who are taking them to help support their journey. In these cases, our work focuses on maximising results, supporting sustainable habits, and addressing any side effects or imbalances that may arise during use.

Common Side Effects and Challenges with Mounjaro

While Mounjaro (tirzepatide) has shown impressive results in helping individuals reduce weight and improve markers of metabolic health, it is not without its challenges.

Many people begin their journey with excitement and high expectations, only to feel confused or discouraged when they encounter side effects or slower progress than anticipated.

Some of the most commonly reported side effects include:

• Nausea and digestive upset – this is perhaps the most common issue, especially when starting or increasing the dose. People may experience nausea, bloating, reflux, constipation, or diarrhoea.
• Reduced appetite or aversion to food – while appetite suppression can be helpful for weight loss, it can sometimes go too far. Some individuals struggle to meet their nutritional needs or develop an unhealthy relationship with food, whilst also negatively impacting their overall health.
• Fatigue or low energy – this may relate to reduced food intake, inadequate protein or nutrient consumption.
• Muscle loss – without a conscious effort to maintain protein intake and resistance training, rapid weight loss may result in a significant loss of lean muscle mass, which can negatively affect long-term health, metabolism and your ability to maintain long term weight loss.
• Mood changes – some people report low mood, apathy, irritability, or increased anxiety while on the medication.
• Plateaus or diminishing returns – while weight loss may be significant early on, many people hit a plateau. Without addressing the underlying metabolic, behavioural, or hormonal drivers, the benefits can stall or even reverse, especially when coming off the medication or even with long term use.

It’s also important to consider the psychological and behavioural impact. For some, Mounjaro creates a sense of reliance on the medication or leads to fear about what will happen when they stop. Others may feel they are “cheating” or bypassing the hard work of behaviour change.

In functional medicine, we recognise that medication can be a useful tool, but it is rarely the whole solution. My work with clients on Mounjaro focuses on:

• Supporting digestion and nutrient absorption
• Preserving muscle mass through tailored nutrition and movement
• Maintaining a healthy relationship with food and appetite cues
• Investigating and addressing side effects when they arise
• Laying the foundation for what happens after Mounjaro

Ultimately, the goal is to help each person feel informed, empowered, heard and supported, not dependent or reactive.

How to Use Mounjaro Effectively to Maximise Results and Minimise Risk

For those choosing to use Mounjaro (tirzepatide), the way it’s integrated into your overall health plan can make a significant difference to both the outcomes you achieve, and the side effects you experience. The medication itself may reduce appetite and improve metabolic markers, but it doesn’t teach the body or mind how to maintain those changes without support.

Here’s how I approach supporting clients to get the most from their time on Mounjaro:

1. Start with a Foundation of Education and Realistic Expectations

Before or early in the process, it’s important to understand:

• This is not a magic fix.
• Side effects are common but often manageable.
• The goal isn’t just to lose weight, but to improve body composition, energy, metabolic flexibility, and long-term habits.
• Having realistic expectations helps prevent disappointment and builds a healthier mindset around progress.

2. Prioritise Protein and Nutrient Density

Mounjaro often leads to a significant reduction in appetite. Without careful planning, this can result in:

• Inadequate protein intake
• Poor exercise performance and recovery from training or activity
• Loss of lean muscle tissue
• Micronutrient deficiencies

I work with clients to create a food plan that ensures you are meeting your protein needs and rich in essential nutrients. Sometimes this means smaller, more frequent meals or easy-to-digest protein options like smoothies, yoghurts, soups, or well-tolerated whole foods.

3. Support Digestion and Reduce Gastrointestinal Symptoms

Nausea, bloating, or reflux are some of the most common challenges. To reduce these, we may explore:

• Eating slowly and mindfully
• Limiting large meals or heavy fats
• Using functional digestive support and prokinetics (e.g., bitters, enzymes, ginger tailored to the individual)
• Tracking symptom triggers and adjusting food choices
• For some clients, supporting stomach acid, bile flow, or gut motility can make a noticeable difference.

Implement Resistance Training and Preserve Muscle

Weight loss alone is not always healthy if it includes a large loss of muscle. Muscle is metabolically protective and essential for long-term health. We emphasise:

• Resistance or strength training 2–4 times weekly
• Progressive overload (increasing challenge over time)
• Monitoring body composition accurately in clinic when possible
• Even if the number on the scale drops, we want to ensure you’re losing fat, not strength and muscle function.

5. Balance Blood Sugar and Energy Levels

Despite improved glucose markers, some clients on Mounjaro experience fatigue, light-headedness, or crashes. This is often related to inconsistent eating, lack of carbohydrates, fats or protein, or poor meal balance.

We assess energy patterns and adjust nutrition to support more stable blood sugar, mood, and energy output.

6. Monitor Mood and Mental Health

A suppressed appetite, low calorie intake, or nutrient deficiencies can all impact mental wellbeing. Plus, the psychological experience of being on medication for weight loss can bring up complex emotions, identity challenges, or even guilt.

We approach this with compassion, curiosity, and support, and where needed, may involve mental health practitioners to support the process as well.

When used with the right mindset, education, and support structure, Mounjaro can be part of a powerful transformation. But it works best when paired with a clear plan for the habits, health foundations, and behaviours that will carry you through long after the medication is stopped.

What Happens When You Stop Taking Mounjaro?

One of the most important and often overlooked conversations to have when starting Mounjaro is what happens next.

For many, the medication is intended as a short to medium-term intervention. But without proper preparation, coming off it can lead to rebound weight gain, metabolic disruption, and frustration.

The Reality of Rebound

Clinical studies and real-world observations show that many people regain a significant portion of the weight lost when stopping GLP-1 or dual agonist medications like Mounjaro. This is not due to failure or lack of willpower, it’s largely because:

• Appetite returns, often quite suddenly
• Acute short-term increases in glycogen and water levels, causing an initial spike in weight that can derail some mentally if they are not prepared for it
• Satiety signals may still be disrupted
• Old habits may creep back in
• Muscle mass may have been lost during the weight loss phase and metabolism levels will likely be lower
• Underlying metabolic issues (insulin resistance, inflammation, etc.) may still be present

This is why I always encourage clients to think of Mounjaro as a window of opportunity to build the habits, behaviours, and physiological resilience that will support long-term health.

Building the Groundwork While on Mounjaro

If you plan to stop or know you’ll eventually need to it’s vital to use your time on the medication wisely. This includes:

• Establishing meal structure and timing: Rather than relying on suppressed appetite, learn what eating patterns suit your energy, mood, and blood sugar best.
• Preserving or building muscle mass: Strength training is essential not only during weight loss, but especially as you come off to help stabilise weight and support metabolism. Developing long lasting strategies for movement and exercise that will last way beyond the use of Mounjaro is critical
• Improving your relationship with food: Emotional eating, binge–restrict cycles, and food fear often resurface when the medication is withdrawn. These patterns must be addressed alongside physical health.
• Optimising your gut and metabolic health: Addressing underlying inflammation, insulin resistance, and digestive imbalances helps the body function more efficiently without medication support.
• Stress and sleep hygiene: These two pillars are often the “silent saboteurs” of weight maintenance. We work to create sustainable, individualised routines that promote nervous system balance.

A Gradual Transition

Coming off Mounjaro doesn’t have to mean a sharp rebound. Depending on the duration and dose, some people benefit from a gradual tapering approach, combined with nutrition and lifestyle guidance as that reduction occurs.

My goal with clients is to ensure that when the time comes, they feel confident, informed, and supported, not anxious or unprepared.

Conclusion: Functional Medicine Support Alongside Mounjaro

Whether you’re just beginning Mounjaro, have already been taking it for a while, or are preparing to come off it, you might find yourself with more questions than answers.

• How do I make the most of this opportunity?
• What if I start regaining weight?
• How do I minimise the side effects?
• Will I just go back to square one when I stop?

These are valid concerns, and they’re exactly why many people choose to work with a functional medicine practitioner like me who specialises in body composition and cardiometabolic health during their Mounjaro journey.

We look beyond the number on the scale to address your energy, sleep, metabolism, gut health, stress resilience, and food relationship. These are the pillars that determine whether your results are sustainable and whether your body is truly thriving.

We work with your feedback and the data we track on your weight loss journey to help inform the decision-making process. This means we can feedback to your prescriber about appropriate dosing as well as make any required changes to your nutrition, lifestyle and perhaps supplementation.

If you want support navigating the challenges and opportunities of using Mounjaro, we can create a tailored support program that complements your medication, supports your body, and sets you up for success, both during and after your time on it.

👉 Learn more about working with me on your weight and metabolic health by visiting my Functional Medicine Support page.

You don’t have to do this alone.

References

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