Why Weight Loss Is Harder with Diabetes and Prediabetes — and What Actually Helps

If you’re living with type 2 diabetes or prediabetes, you may have already discovered an uncomfortable truth: weight loss often feels harder than it “should” be.

And when you’ve tried repeatedly — eating “well”, starting again on Monday, losing a little, regaining it — it can start to feel personal. Like a motivation problem. Like a willpower problem.

It usually isn’t. For many people, weight gain and difficulty losing weight are the visible surface of deeper biology (hormones, appetite signals, sleep, stress), layered on top of real life (work, family, costs, fatigue, habits built over decades).

This page is a practical, story-led overview of why weight loss is harder with diabetes and prediabetes — and the strategies that actually work. If you want a higher-level starting point, begin at our main hub: Weight Loss and Diabetes: What Really Works.

If you’re feeling stuck and want a clear plan, you may find it helpful to watch one of my free masterclasses: Type 2 Diabetes Masterclass or Prediabetes Masterclass. They’re designed to make the “why” feel obvious — and the “what next” feel doable.

Why weight loss is harder with diabetes and prediabetes

Let’s start with the most important reframe: your body is not neutral about weight loss. When you lose weight, your biology often responds as if something has gone wrong — hunger rises, fullness signals weaken, and your body becomes more efficient at using energy.

In diabetes and prediabetes, that “pushback” is often stronger because the underlying metabolism is already under strain. For many people, the driver is insulin resistance — but not every person with weight challenges has insulin resistance, and not every person with insulin resistance looks the same. (If you want a clear explanation, start here: What is insulin resistance?)

Here are the common reasons weight loss feels harder in real clinics (not just in theory):

• Higher hunger, lower satiety. The body defends its usual intake, especially after dieting. If this feels familiar, you’ll recognise the “I was fine all day… then I ate everything at night” pattern.
• Energy efficiency. After weight loss your body often burns fewer calories than expected for your size — sometimes called metabolic adaptation. (We explore this idea in: adaptive thermogenesis.)
• Time pressure and inconsistency. People don’t fail because they “don’t know what to do” — they struggle because they’re busy, tired, stressed, and trying to fit health into real life. (See: too busy to manage type 2 diabetes and too busy to manage prediabetes.)
• Medication effects. Some diabetes medications support weight loss, some are weight neutral, and some can push weight up — especially if doses aren’t matched to your changing body and activity.

This is why the most effective weight-loss plans for diabetes aren’t “diet plans”. They’re systems — designed around appetite, routine, emotions, sleep, movement, and medical therapy when needed.

Insulin, appetite, and the “hungry brain”

Many people hear “insulin” and think it only relates to injections. But insulin is also one of the major hormones involved in energy storage and appetite regulation. In prediabetes and type 2 diabetes, insulin levels can be higher than you’d expect for years before diagnosis, because the body is trying to overcome insulin resistance.

Put simply: when the body becomes resistant to insulin, it often needs more insulin to do the same job — and that can make fat storage easier and fat loss harder. (If you’d like the deeper “why”, see: Causes of insulin resistance and insulin resistance and belly fat.)

This is also why some treatments can support weight loss by helping the body work with appetite instead of fighting it:

• Metformin can improve insulin sensitivity in some people and may modestly reduce appetite. If metformin upsets your stomach, don’t “push through” blindly — there are practical ways to reduce side effects: metformin and diarrhoea.
• GLP-1 medications work through the brain–gut appetite system — helping you feel fuller sooner, and making it easier to eat less without constant hunger. (If you’re exploring options: Victoza, exenatide-based therapies, and Mounjaro.)
• If insulin is part of your treatment, weight loss is still possible — but your plan must match your insulin. A useful starting point is: Insulin explained and Basal insulin. (And if you’re adjusting insulin, always do it with your clinician to avoid hypos.)

If you want an immediate “where am I right now?” check-in, our HbA1c Converter and Target Tool can help you understand what your result means — and what a sensible next step could be.

And if you prefer video, start with: Insulin resistance (video).

Stress, sleep, and emotional eating

Weight loss doesn’t happen in a lab. It happens in kitchens, workplaces, car rides, shift work, relationship stress, grief, loneliness, and exhaustion.

Two of the biggest hidden drivers of weight regain are stress and sleep. When stress is high and sleep is low: hunger hormones tend to rise, cravings intensify, patience shrinks, and the brain starts looking for quick comfort.

If you’ve ever found yourself eating “not because you’re hungry, but because you need relief” — that’s not a character flaw. It’s a human brain under load. (Related reads: Why do we eat when we are not hungry? and Good stress, bad stress, and distress.)

Sleep matters more than most people realise. Poor sleep can worsen insulin resistance and appetite regulation — making the next day feel like an uphill battle from breakfast. See: sleep habits and insulin resistance.

The strongest long-term plans include behavioural tools that reduce “all-or-nothing” swings. If you like practical psychology without fluff, explore:

• Mindfulness and diabetes
• Mindfulness and prediabetes
• Perfectionism and diabetes
• Perfectionism and prediabetes
• Thinking style and diabetes
• Thinking style and prediabetes

If you want the “big picture” explained step-by-step (without judgment), the free masterclasses are designed exactly for this stage: Type 2 Diabetes Masterclass and Prediabetes Masterclass.

Plateaus, weight regain, and the biology of “bounce back”

Most people don’t struggle to lose any weight. They struggle with the middle part: the plateau… the slow drift… the regain… the frustration… the stop-start cycle.

Plateaus happen for a few predictable reasons: you’re lighter so your body needs less energy, your routine becomes less consistent over time, appetite pushes back, and “treats” quietly become daily. None of this means you’ve failed — it means you need a better system.

A simple (and surprisingly powerful) strategy is to stop treating movement as “exercise sessions” and start using it as a tool to reduce glucose spikes and improve insulin sensitivity across the day. See: exercise snacking and how to improve insulin sensitivity.

What actually works (and what to do next)

The best approach depends on your health, your preferences, your medications, and what you can sustain. But most successful plans include three layers:

• Food strategy that is realistic. If you want a structured starting point, visit our diet sub-hub: Diet & Weight Loss Strategies. Helpful reads include carbohydrates and diabetes, reducing carbs, and low-carb: is it right for you?.
• Behaviour strategy that survives real life. This is where stress, sleep, habits, and support matter. If you’ve been doing it alone, consider reading: support in type 2 diabetes.
• Medical strategy when needed. For many people, medications aren’t a “shortcut” — they’re a way to align biology with effort. Explore GLP-1 medications, metformin, and if insulin is part of your care, insulin explained.

Two final “modern life” factors worth naming: portion size and pricing psychology. If you’d like the thought-provoking angle, read our news pieces: Portion size, weight loss, and diabetes and Non-linear pricing and obesity. These aren’t about blaming people — they’re about understanding the environment we’re all living in.

If you want a guided explanation of what to prioritise first (and why), choose the masterclass that fits you: Type 2 Diabetes Masterclass or Prediabetes Masterclass. Many people find that once the logic “clicks”, the next steps finally feel clear.