Weight loss in the Over-65s

Posted on September 23, 2026 by Sally-Anne Turner

Can Mounjaro Injections Help?

Are you an older person who wants to lose weight? Have you read about Mounjaro injections and wondered whether this GLP-1 could help you?

As the UK population continues to live longer, secondary questions arise about mobility, longevity, and, of course, weight loss. According to the NHS, as many as 7 in 10 adults aged 65–74 is overweight or living with obesity, with approximately 35% living with obesity.

Interestingly, we have noticed a shift in our demographics at the Bodyline Clinic, with more people approaching us for weight loss later in life.

We are different from other GLP-1 providers at the Bodyline Clinic. We take the time to get to know our patients and work with you to meet your weight loss goals. Our dedicated clinical team will assess your health throughout your journey and adjust your dosages as needed. With over 18 years of experience and over 100,000 patients helped, we know how to make your weight-loss journey a success.

Choosing the right medication to help you lose weight can be tricky. Many people cannot decide between oral options and weight-loss injections. So, we will walk you through Mounjaro (tirzepatide) to help you see whether Mounjaro injections could help you lose weight later in life.

What is Mounjaro?

Mounjaro is the brand name for tirzepatide.

Tirzepatide is a GLP-1/GIP agonist. When injected, it increases both of these incretins (hormones) in your body. It can also help with diabetes by prompting your body to produce more insulin when needed. This helps lower blood sugar levels and makes you feel full.

At the time of writing, Mounjaro is available only by injection.

Can Older People Take Mounjaro?

In a word, yes.

The core issue is that clinical data on Mounjaro include limited data for people over 65. This means that many UK online pharmacies that offer this as a treatment will say no to people in this age group. The licence for Mounjaro has no upper age cut-off. The SmPC for Mounjaro notes that older adults need no dose adjustment based on age, including once they reach a Mounjaro maintenance dose. Clinically, there is no need to change the starting dose or the escalation schedule.

Our team at the Bodyline Clinic has a guide on what a typical Mounjaro dose increase may look like, so feel free to check it out.

The SmPC does flag some side effects that warrant particular clinical oversight in the elderly, which include:

1. Mounjaro nausea, vomiting and diarrhoea. These are gastrointestinal side effects of GLP-1 treatment which, in the elderly, can result in significant fluid loss. Mounjaro diarrhoea and vomiting can be particularly important in an older person because of the increased risk of dehydration.
2. Dehydration and electrolyte imbalances. This is a particular concern in elderly patients, as they are at a higher risk of falls due to these complications
3. Issues with kidney function/acute renal failure. Linked to dehydration, this GI side effect can impair renal function.
4. Hypoglycaemia. This is more of a risk in those with type 2 diabetes who are taking insulin or a sulphonylurea. Note that this isn’t unique to the elderly and should be monitored across all age groups.
5. Hypotension and dizziness. An adverse reaction in those being treated for weight management. Dehydration can make these important to monitor in an older patient, who may be frail.

One other thing. The SmPC notes extremely limited data for patients aged ≥85 years. Mounjaro is not contraindicated but, as with all GLP-1s, it can make symptom management more specialised.

What do the Studies Say?

Some studies have inadvertently examined how Mounjaro may affect an older person’s health.

A 2026 post-hoc analysis of data from the SURMOUNT-1 to -5, SURMOUNT-OSA and SUMMIT compared adults ≥65 with those <65.

It determined that tirzepatide created clinically relevant weight loss in those over the age of 65. Of course, the researchers noted that weight loss in older people needs more clinical oversight due to;

1. Age-related loss of muscle and bone.
2. Sarcopenia.
3. Nutritional deficiencies.
4. Functional decline.
5. Fractures.

SURMOUNT-1 and Body Composition

In SURMOUNT-1, a DXA scan (bone density test) explored the kind of tissue that people lost while taking tirzepatide. After 72 weeks of treatment with tirzepatide, there was approximately

1. 21.3% body weight
2. 33.9% fat mass
3. 10.9% lean mass

So, around 75% of weight loss was fat and 25% lean mass. Researchers in this study analysed people ≥65 and noted that the proportion of fat versus lean-mass loss was broadly similar across age groups. These Mounjaro results are particularly relevant when considering treatment in those over the age of 65, who may already have sarcopenia or lower muscle reserves.

In older people who already have lower muscle reserves or sarcopenia, this will need additional monitoring and dose adjustment as needed.

SURPASS Analysis ≥65

A 2025 post-hoc analysis of the SURPASS-1 to SURPASS-5 trials looked at 540 adults aged 65 and over with type 2 diabetes and a BMI of 23 to <30 kg/m²

These older patients were noted to have:

1. longer-standing diabetes
2. lower kidney function
3. lower starting body weight
4. numerically lower weight loss
5. a greater likelihood of discontinuing tirzepatide because of adverse events.

With the oversight of the clinical team, they made meaningful improvements in HbA1c and dose-dependent weight reduction.

This highlights what we have always promoted at Bodyline: even with complex medical histories, you can still lose weight with the right clinical support.

Why Dehydration Matters More

Clinical trial data suggest that dehydration itself is uncommon, occurring in around 3 in every 1,000 people taking tirzepatide.

Gastrointestinal effects like nausea, vomiting, and diarrhoea can lead to dehydration. In older people, this can impact kidney function. For those over the age of 65, this can be serious and is why older people who take Mounjaro are advised to stay more hydrated when suffering from GI side effects.

Alongside kidney issues and electrolyte disturbances, dehydration from Mounjaro in older people increases the chances of:

1. Low blood pressure/hypotension. This can contribute to weakness, light-headedness or dizziness.
2. Increased risk of falls. When dehydration contributes to dizziness, weakness or postural hypotension, older people may fall more easily. If they are frail, they are at a higher risk of fractures.
3. Confusion or changes in cognition. When dehydration becomes significant, older adults are more prone to illness-related confusion.
4. Physical weakness and decline. This is more worrying if someone is already frail or has limited/reduced muscle reserves.
5. Complications of existing health conditions. Worsening renal or cardiovascular disease, changes in fluid volume, blood pressure and electrolyte balance may need closer monitoring.

Please note that these symptoms do not mean stopping Mounjaro. However, discuss significant or persistent side effects with your clinical team. Coming off Mounjaro may be advisable if side effects cannot be safely managed or if the treatment is no longer appropriate.

Elderly Weight Loss at Bodyline

When it comes to choosing where to go to lose weight, you may feel the best option is the cheapest.

A quick five-minute call, a sign-off on a prescription and voila! You are on your way to losing weight. However, if you are older or have a condition that could prevent you from getting access to GLP-1s from a pharmacy, you will need more than a quick consultation.

At the Bodyline Clinic, our core difference from other GLP-1 providers is that we offer specialised weight loss care for:

1. People over 75.
2. People with a diagnosed mental health issue.
3. Patients who have gastrointestinal issues, like Crohn’s.
4. Those who have cardiovascular disease.

However, we offer additional personalised clinical oversight to all of our patients. Why? Because your health matters.

If you have been wanting to start weight loss with Mounjaro, or another GLP-1, we may be able to help you. So, contact our team today on 0800 995 6036 or drop us an email on our site and let’s start your weight loss journey.

Bodyline works. Bodyline cares.

FAQs

How Long Does Mounjaro Take to Work?

For appetite suppression, Mounjaro starts working within hours after injection. For visible weight loss, people may be waiting for 2-4 weeks before noticing a change. Most significant results happen within 3-6 months, on average.

Does Mounjaro Make You Tired?

Mounjaro (tirzepatide) can cause fatigue or tiredness. Indeed, this has been reported in around 5-10% of clinical trial participants. If the fatigue interferes with your daily functioning, please contact a GP for advice.

Can You Drink Alcohol on Mounjaro?

You can drink alcohol when taking Mounjaro. However, caution is advised due to the impacts that alcohol can have on blood sugar and gastrointestinal health.