GLP-1s have a proven place in type 2 diabetes. Now they’re turning heads in type 1.
by Dr Paula Diab, PhD, CDCES Diabetologist & Weight Management Specialist
If insulin is essential in type 1 diabetes, why are we increasingly talking about adding other therapies?
It’s a question that comes up more and more and one that reflects how our understanding of type 1 diabetes is evolving. While insulin remains the cornerstone of treatment, many people living with type 1 diabetes today are facing challenges that insulin alone doesn’t fully address: weight gain, rising insulin requirements, and persistent glucose variability despite best efforts.
Recently, Gary Scheiner and I hosted a webinar addressing the use of GLP1s in type 1 diabetes. If you didn’t get an opportunity to view the webinar, please contact our office and ask for a recording, or have a look at our Type 1 University course, GLP-1s & T1D: The Real Story.
GLP1s are well established in type 2 diabetes and obesity care, but their role in type 1 diabetes is becoming increasingly very exciting.
Why Consider GLP-1s in Type 1 Diabetes?
Traditionally, type 1 diabetes has been viewed purely as a condition of insulin deficiency. But in clinical practice, the picture is often more complex.
Many people with type 1 diabetes:
- Experience weight gain over time
- Develop features of insulin resistance
- Require progressively higher doses of insulin
This has led to the concept of “double diabetes” – where type 1 diabetes coexists with metabolic features more commonly associated with type 2 diabetes, such as weight gain, increased appetite and insulin resistance.
GLP-1 receptor agonists offer a different mechanism of action that may complement insulin therapy.
Their effects include:
- Slowing gastric emptying
- Enhancing satiety and reducing appetite
- Reducing post-meal glucose excursions
In carefully selected individuals, these effects can support more stable glucose patterns and reduce some of the daily burden of managing diabetes. Importantly, this is not about replacing insulin – it’s about augmenting its effects.
What Does the Evidence—and Experience—Show?
The clinical trial data for GLP-1 use in type 1 diabetes is still limited and somewhat mixed.
Studies have shown modest but meaningful benefits, including:
- Weight reduction
- Decreased total daily insulin dose
- Improvements in postprandial glucose control
However, the real insight often comes from clinical experience. In our recent discussions, a consistent theme emerged: for some individuals, GLP-1 therapy changes the experience of living with diabetes.
Patients frequently report:
- Less “food noise” or constant preoccupation with eating
- Greater ease in following structured nutrition plans
- Fewer large post-meal glucose spikes
These changes may not always translate into dramatic shifts in HbA1c, but they can significantly improve day-to-day management and quality of life.
That said, responses are highly individual. Some patients experience meaningful benefits, while others find little change or struggle with side effects. As with many aspects of diabetes care, there is no one-size-fits-all solution.
Safety Considerations: Where We Need to Be Careful
As interest in GLP-1 therapy grows, it is essential to approach its use in type 1 diabetes with caution and clarity.
One of the most important risks to be aware of is the potential for ketone formation and euglycaemic diabetic ketoacidosis (DKA). This can occur if insulin doses are reduced too aggressively, particularly in the context of reduced appetite and food intake.
Other considerations include:
- Gastrointestinal side effects (such as nausea and delayed gastric emptying)
- Changes in glucose patterns that may alter hypoglycaemia risk
- The potential for under-bolusing due to reduced food intake
A key principle we emphasised in our discussion is this: GLP-1 therapy does not replace insulin – it changes how we need to use it.
Insulin remains essential for metabolic stability. Any adjustments to dosing must be thoughtful, gradual, and closely monitored.
Practical Use
In practice, success with GLP-1 therapy in type 1 diabetes depends less on the medication itself and more on how it is introduced and supported.
- Patient selection is key
GLP-1 therapy may be most helpful for individuals who:
- Are experiencing weight gain or obesity
- Require higher insulin doses
- Have significant post-meal glucose excursions
- Feel overwhelmed by appetite or food-related decision-making
2. Start low, go slow
Gradual dose titration helps minimise side effects and allows time to adjust insulin safely.
3. Maintain insulin structure
- Basal insulin should remain stable to ensure safety
- Bolus adjustments should be cautious and data-driven
- Avoid the temptation to reduce insulin too quickly
4. Education is essential
Patients need clear guidance on:
- Recognising and checking for ketones
- Adjusting meal patterns as appetite changes
- Understanding expected effects versus warning signs
How can we play a role?
The introduction of adjunct therapies like GLP-1s highlights an important truth: diabetes management is increasingly complex—and best approached as a team effort.
Successful use of GLP-1 therapy in type 1 diabetes often requires:
- Careful insulin adjustment
- Nutritional guidance tailored to changing appetite
- Ongoing monitoring and education
- Support for behavioural and emotional aspects of care
This is where a multidisciplinary approach becomes invaluable. Having access to experienced clinicians, educators, and dietitians allows for safer initiation, more effective titration, and better long-term outcomes.
At IDS, our clinicians have a host of skills that enable us to share lived experience and clinical expertise as you navigate all the changes in your diabetes management. We can also assist with a baseline assessment and motivation to your primary care physician if necessary.
Where Are We Heading?
The growing interest in GLP-1 therapy in type 1 diabetes reflects a broader shift in how we think about the condition. We are moving beyond a purely insulin-centric model toward a more integrated understanding of metabolism—one that recognises the roles of appetite regulation, insulin sensitivity, and overall metabolic health.
Looking ahead, we are likely to see:
- More research into GLP-1 and dual agonist therapies in type 1 diabetes
- Greater individualisation of treatment strategies
- Continued integration of pharmacological, technological, and behavioural approaches
But even as new tools emerge, the fundamentals remain unchanged. GLP-1 receptor agonists are not a solution for everyone with type 1 diabetes. They are not a shortcut, and they are not without risk. However, in the right context, for the right individual, and with the right support, they can offer a meaningful addition to the treatment toolkit.
The future of type 1 diabetes care is not about using less insulin – it is about using all our tools more thoughtfully, more safely, and more effectively.
