The Diagnosis That Wasn’t: Mark’s 28-Year Journey to the Truth

And Mark believed them.

When Insulin Doesn’t Add Up

Mark, originally from Australia and now living north of London in the UK, began his diabetes management with Levemir and Novorapid — a regimen usually reserved for T1D. But the numbers never quite made sense.

“My dosages just kept on climbing,” said Mark. “I started out on 15 or 20 units of Levemir a day and six units of rapid-acting insulin for meals. That got adjusted a few times, but I just needed more and more.”

Eventually, Mark was taking 250 units of insulin a day — 100 units of Levemir and 150 units of Novorapid — and he still wasn’t within range.

“It didn’t matter how much I adjusted things. My blood sugar just wouldn’t stay in range,” he said. “But nobody ever questioned whether I was really type 1.”

Years of Burnout and Complications

By Mark’s early 40s, the emotional weight of the diagnosis began to wear him down.

“I sank into diabetes burnout really badly,” he shared. “I stayed in that burnout phase for at least 10 years. I couldn’t even check my blood sugar once a day.”

In 2014, Mark developed diabetic retinopathy. Diabetic retinopathy is a common diabetes complication caused primarily by chronically high blood sugar levels. The excess sugar in the bloodstream will essentially damage and destroy the nerve endings and blood vessels in the eyes, and potentially in other organs throughout your entire body. 

With annual eye exams to identify the earlier stages of retinopathy, today’s treatment options can stop the condition from worsening, protect your vision, and potentially restore lost sight. Getting your blood sugar levels down to a safer range is critical to prevent further damage.

Multiple laser surgeries followed, and his eyesight became a new concern in an already overwhelming health journey.

The Breaking Point

By mid-2019, job stress was pushing Mark past his limits.

“My company was on its third round of job cuts in two years, and it was clear they wanted me gone,” he said. “I’d get off the train and feel like throwing up before I even got to the office.”

His doctor signed him off work for stress leave. That’s when Mark realized he needed to choose his health over his job. He took a severance package and left. Everything changed that year on World Diabetes Day when he had bloodwork done. His A1C came back at 8.9 percent.

“I went to my GP, and all they said was, ‘lose weight and watch what you eat,’ with no actual advice on how to do that,” said Mark. “I asked about a CGM, but they said, ‘You’re type 2, you’re not entitled to one on the NHS.’”

A New Chapter Begins

Mark didn’t accept that answer. He ordered his own Libre sensor directly from Abbott.

His first CGM sensor arrived on December 19, 2019. By Christmas, he had switched to a low-carb diet — and everything began to change.

By February 2020, his A1C had dropped to 6.6 percent.

“Once I could see the sensor data, it all clicked,” he said. “I started asking, ‘What can I do? What can I eat to change this?’”

He’s now lost 24 kilos (59 lbs.) and continues to make progress. His weight today is 110 kilos (242 lbs), and he is heading in the right direction.

A Correct Diagnosis, at Last

It wasn’t until 2023 — nearly 30 years after his initial diagnosis — that Mark finally had a C-peptide and autoantibody test.

The results confirmed what he had long suspected: he did not have T1D. He had type 2 diabetes (T2D) all along.

The news was both validating and infuriating. After nearly three decades of believing he had a condition that required lifelong insulin dependence, he finally had clarity — and the freedom to explore new approaches to his health.

Better Tools, Better Results

Since then, Mark’s approach to treatment has completely shifted. He now uses Mounjaro (tirzepatide), a medication that has made a significant difference.

“My insulin use has gone from 40 units of Levemir and 60 units of NovoRapid down to 35 units of Levemir and 20 units of NovoRapid,” he said. “It’s really helped with appetite, too.”

Mark also uses a Noctura400 mask at night to help manage his eye health. The mask reduces the demand for oxygen in the eyes, targeting the root cause of diabetic retinopathy—hypoxia. After 12 months of using the mask, his eye doctor reported no new bleeding and significant improvement.

“It’s also improved my night vision,” he said. “Unless I can improve the blood circulation in my eyes, I’ll need to keep using it, but it’s worth it.”

From Burnout to Advocacy

Today, Mark works in niche software development and advocates for better access to CGMs for people with type 2 diabetes in the UK. He’s also working to reduce the stigma that people with type 2 diabetes often face.

“Being misdiagnosed took away my sense of agency and autonomy,” he said. “It shouldn’t take decades to get the right answers.”

Mark hopes that by sharing his story, others will feel empowered to ask more questions, seek second opinions, and advocate for the tools and care they deserve.

Know Your Diagnosis — Advocate for Yourself

Mark’s story is an important reminder: you have the right to understand your diagnosis. If something doesn’t feel right — speak up. Ask for the tests. Push for clarity. Don’t let assumptions about your age, weight, or background stand in the way of getting the care you need. Advocacy isn’t just an option — it can be the difference between decades of mismanagement and finding your way forward.