Signs and Symptoms of Prediabetes

Medically reviewed by Dr Sultan Linjawi, Endocrinologist & Diabetes Specialist — January 2026

Part of:What is prediabetes or borderline diabetes and does it matter?
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Prediabetes symptoms are usually subtle — and many people have no symptoms at all. When symptoms do show up, they’re often linked to insulin resistance and early changes in how your body handles glucose.

This matters because prediabetes is the stage where progression to type 2 diabetes is often preventable — but only if it’s recognised and acted on early. If you’re unsure whether what you’re feeling “counts”, the safest move is not to guess: check your risk and consider a simple blood test.

What helps most (in real life)

  • Confirm the diagnosis with the right tests (don’t rely on symptoms alone)
  • Target insulin resistance with sustainable weight + waist reduction strategies
  • Move most days (walking + resistance training is a powerful combination)
  • Improve sleep (especially if snoring or sleep apnoea is likely)
  • Choose food changes you can repeat (protein + fibre first, refined carbs down)

If you’d like the “big picture” explained simply (symptoms + tests + what to do next), you can join the free Prediabetes & Insulin Resistance Masterclass.

Start where you are

People land here for different reasons. Use this quick guide to go straight to what you need:

If you prefer an external reference, see: CDC – Prediabetes Basics and NIDDK – Prediabetes & Insulin Resistance.

How this page fits into your learning

My Health Explained is designed to help you understand diabetes over time, not all at once. Most people arrive with one specific question, then build confidence as new questions come up.

This page covers one important part of that picture. You'll see links throughout to related topics that explain why things happen, what options exist, and what tends to help in real life.

If you'd like a broader overview first, start here: What is prediabetes or borderline diabetes and does it matter?.

If something here raises a question, follow the links that feel most relevant and ignore the rest for now. This resource is built to support learning at your own pace.

Early signs you may notice

Many symptoms of prediabetes relate to the body struggling to keep glucose levels in a healthy range. These can be subtle, inconsistent, or easy to attribute to lifestyle pressures.

1. Increased thirst

Mild dehydration can occur when excess glucose draws water into the urine. This isn’t usually as dramatic as in type 2 diabetes, but some people notice they are drinking more than usual, especially in the evenings or overnight.

2. More frequent urination

As blood sugars begin creeping higher—even within the “prediabetes” range—the kidneys may pass more urine to keep glucose under control. You might find yourself going to the toilet more often, particularly at night.

3. Increased hunger (even after eating)

If your body becomes less responsive to insulin, glucose does not move efficiently into the muscles for energy. This can trigger “cell-level hunger”, leading to cravings or overeating even when you have eaten enough.

To understand the background process, it can help to review:

For a simple overview of prediabetes and insulin resistance, the CDC also provides a helpful summary: CDC – Prediabetes Basics.

Skin, weight & hormonal symptoms

4. Darkening of the skin (acanthosis nigricans)

A velvety, darker patch of skin—commonly around the neck, underarms, or groin—can be a visible sign of high insulin levels. This is one of the strongest physical markers of insulin resistance and should always prompt further testing.

5. Weight gain around the stomach

Central or abdominal weight gain is strongly linked with worsening insulin sensitivity. Many people notice that their waistline increases even if they do not feel they are eating more than before. This “apple-shaped” pattern is closely associated with prediabetes and metabolic syndrome.

6. Polycystic ovary syndrome (PCOS) features

Prediabetes often coexists with polycystic ovary syndrome in women. Symptoms can include irregular or absent periods, acne, excess hair growth on the face or body, and difficulty losing weight. PCOS is strongly associated with insulin resistance, even when blood glucose levels are not yet in the diabetes range.

If you are concerned about underlying insulin resistance or metabolic health, you may find these resources helpful:

Energy, sleep & mood symptoms

Many people with prediabetes report feeling unusually tired, mentally foggy, or unrefreshed after sleep. These symptoms are often early metabolic warning signs, but they are easy to blame on work, family demands, or “just getting older”.

7. Fatigue and low energy

When glucose does not enter the cells efficiently, the body cannot generate energy optimally. This can lead to:

  • Persistent tiredness
  • “Brain fog” or feeling mentally slow
  • Difficulty concentrating or staying motivated

Many people only realise how affected they were once their glucose control improves. For a deeper dive into this topic, see: Why Do I Feel So Tired With Prediabetes?

8. Poor-quality sleep or sleep apnoea

Insulin resistance and obstructive sleep apnoea commonly occur together. Signs include loud snoring, pauses in breathing during sleep, waking unrefreshed, morning headaches, or needing daytime naps. Disturbed sleep further worsens insulin resistance, creating a vicious cycle.

9. Mood changes

Fluctuating glucose levels and chronic fatigue can affect mood, making it harder to cope with daily stresses. People with prediabetes may notice:

  • Irritability or feeling “on edge”
  • Low mood or loss of enjoyment
  • Increased anxiety or worry about health

If this resonates with you, you may also want to explore: Prediabetes and Mental Health.

If these symptoms feel familiar, Dr Sultan explains the underlying biology and practical next steps in the free Prediabetes & Insulin Resistance Masterclass. It’s a simple, no-jargon way to understand what is happening in your body and what you can do about it.

When should you get tested?

Testing is recommended if you notice any of the symptoms above—especially if you also have risk factors such as family history of type 2 diabetes, a history of gestational diabetes, abdominal weight gain, high blood pressure, or age over 40.

Common tests include:

  • Fasting plasma glucose
  • Oral Glucose Tolerance Test (OGTT)
  • HbA1c (best interpreted alongside other tests, not in isolation)
  • In some cases, specific tests for insulin resistance

You can read more about how prediabetes is diagnosed here:

The NIDDK also provides an overview of prediabetes and testing approaches: NIDDK – Prediabetes & Insulin Resistance.

What should you do next?

If you recognise these symptoms, the most important step is not to ignore them. Prediabetes is the stage where lifestyle changes have the greatest impact and reversal is genuinely possible.

Good next steps include:

Remember: it is not “having prediabetes” that causes most of the long-term harm, but living for years with elevated blood sugars and unrecognised insulin resistance. Acting early makes all the difference.

Free Prediabetes & Insulin Resistance Masterclass

If you would like a clear, step-by-step explanation of what your symptoms mean, how to interpret your blood tests, and what to do next, you can join Dr Sultan’s free Prediabetes & Insulin Resistance Masterclass.

In around 40 minutes you’ll learn how to reduce your risk of type 2 diabetes, improve your energy levels, and build a practical plan you can actually stick to.