Why Insulin Resistance is Missed — and How Metabolic Surgery Changes the Game

(Part 2 of 3 in our Insulin Resistance Series)

In Part 1, we introduced insulin resistance as the hidden driver behind stubborn weight gain, cravings, and even weight regain after bariatric surgery. But here’s the real problem: in the UK, insulin resistance is almost invisible in standard healthcare.

Why Insulin Resistance Gets Missed in the UK

Most GPs can only request two tests to look at blood sugar: fasting glucose and HbA1c. These are useful for diagnosing diabetes, but they miss the earlier stage — when insulin is already running high, but blood sugar still looks “normal.”

By the time an HbA1c rises to the prediabetes or diabetes range, insulin resistance has often been active for years. Patients with clear symptoms — hunger after meals, weight gain around the middle, brain fog, constant tiredness — are frequently told: “your bloods are fine.”

This gap means people struggle on, often blaming themselves, when their biology is actually crying out for help.

Other Clues Doctors Might Overlook

Even without fasting insulin testing, there are patterns that point to insulin resistance:

• A high triglyceride:HDL ratio

• Central obesity or “apple-shaped” weight gain

• Skin changes like skin tags or dark patches (acanthosis)

• A strong family history of type 2 diabetes

• Rapid weight regain after diets or sleeve surgery

These aren’t always checked, or they’re dismissed as cosmetic issues. But together, they tell a story.

Beyond Restriction: Surgery as Metabolic Treatment

When most people think of bariatric surgery, they think of restriction — smaller stomachs, reduced appetite, less food. But the real revolution is in metabolic surgery. These procedures change the way the gut and pancreas talk to each other, triggering powerful hormonal shifts.

• GLP-1 and other gut hormones rise, improving satiety and insulin sensitivity.

• Fasting insulin drops, even before significant weight loss.

• Blood sugar and HbA1c improve within weeks, not years.

This isn’t just about eating less. It’s about resetting the body’s chemistry.

Not All Surgeries Are Equal

• Gastric Sleeve: highly effective for weight loss, but primarily restrictive. Many patients do see metabolic improvements, but some insulin resistance lingers.

• Roux-en-Y Gastric Bypass: stronger hormonal effects, often leading to higher rates of diabetes remission.

• Mini Gastric Bypass (MGB): increasingly recognised as one of the most effective procedures for improving insulin resistance and type 2 diabetes. For patients revised from sleeve, MGB can act as a “metabolic reset.”

When Sleeve Isn’t Enough

Sleeve surgery remains one of the most popular procedures worldwide. But for patients whose insulin resistance persists — who continue to struggle with grazing, cravings, or slow improvements in HbA1c — revision to Mini Gastric Bypasscan provide a second chance.

This isn’t about failure. It’s about tailoring the right tool to the right biology.

Looking Ahead

Insulin resistance is not rare — it’s just ignored. And it can be treated. Metabolic surgery stands as one of the most powerful options available, especially when standard restriction isn’t enough.

In Part 3 of this series, we’ll look at practical steps to reduce insulin resistance — from diet, exercise, and medication, through to surgical options for those who need them.