Insulin Resistance & Blood Sugar Imbalance: Key Warning Signs to Watch For

06 Nov 2025

Keeping blood sugar levels in a healthy range is crucial for long-term health. However, many individuals harbour hidden signs of blood sugar imbalance or insulin resistance long before a diagnosis of diabetes. Early identification is very important because addressing these changes early enough not only allows for appropriate management, but more importantly, can prevent the onset of more severe conditions such as heart disease, type 2 diabetes, or metabolic syndrome.

At London GP Clinic, our private health screening and blood testing services actively help patients identify insulin resistance, elevated fasting blood glucose, and HbA1c abnormalities early enough for lifestyle modifications andother treatments to be effective.

Understanding Blood Sugar and Insulin

When we eat, our carbohydrates are digested and converted into glucose – the body’s primary energy source. Insulin is a hormone produced by the pancreas that helps the absorption of glucose by our cells from the bloodstream.

However, if the cells of the body do not accept the insulin effect or become less responsive to the hormone, glucose levels remain in the blood rather than being used for energy. When this occurs, insulin resistance is developed. At some point, and as the body continues to increase the insulin production response in the pancreas, the body often fails to keep up with it. This results in chronic high blood glucose levels.

This period – when your blood sugar levels are elevated, but you are not diagnosed with diabetes – is called prediabetes or impaired glucose tolerance. It is a crucial point for you to act on early.

What triggers Insulin Resistance?

Insulin resistance develops slowly, and can be affected by different lifestyle, hormonal or genetic factors. The most prevalent causes triggering insulin resistance are:

• Poor dietary choices: Having excessive sugary foods, processed snacksand refined carbohydrates.
• Obesity, specifically around the abdomen (visceral fat).
• Lack of movement: Not exercising regularly has been shown to decrease the body’s insulin sensitivity.
• Hormonal imbalances, such as a diagnosis of polycystic ovary syndrome (PCOS).
• Chronic stress: This leads to increased cortisol levels and impacts glucose metabolism.
• Poor sleeping habits: Not getting enough sleep impairs the ability for your body to regulate insulin.
• A family history of diabetes or metabolic syndrome.

You will have a considerable impact on your health outcomes by identifying and addressing risk factors early.

Early Signs of Blood Sugar Imbalance

Blood sugar imbalance can present in subtle ways, and most people often do not notice early signs. Common signs are:

1. Persistent fatigue or low energy: You feel tired or fatigued almost all the time, even after adequate rest.
2. Increase hunger and sugar cravings: You find yourself craving carbohydrates or sugar.
3. Frequent thirst and urge to urinate: Symptoms of high blood glucose levels.
4. Unexplained weight gain or difficulty losing weight: Especially around the abdomen.
5. Brain fog and difficulty concentrating: A result of fluctuating glucose levels.
6. Mood swings or irritability: Frequently fluctuating blood sugar levels can have an impact on stable mood.
7. Skin changes: Dark patches (acanthosis nigricans) on the armpits or neck when insulin resistance is present.
8. Irregular menstrual cycles in women: Significant in regards to PCOS.

Since these are typically non-specific symptoms, the best way to measure metabolic health is through consistent blood work.

The Importance of Early Diagnosis

Insulin resistance tends to develop silently for years before it is directly diagnosed. By the time symptoms are present, significant metabolic changes can take place.

If diagnosed early, lifestyle modification and medical management, if appropriate, will help restore normal insulin sensitivity. This helps:

• Prevent or delay type 2 diabetes.
• Decrease the likelihood of cardiovascular disease.
• Improve focus, energy, and weight management.
• Improve metabolic and hormonal balance overall.

How is Insulin Resistance diagnosed?

At London GP Clinic, your doctor may advise one or more of the following blood tests to assess blood sugar and insulin levels:

1.      Fasting Blood Glucose Test

This checks your blood sugar after an overnight fast and usually, normal values are somewhere in the range of 4.0 and 5.4 mmol/L.

2.     HbA1c (Glycated Haemoglobin) Test

This indicates what your average blood sugar level has been over the preceding 2 to 3 months. A result between 42–47 mmol/mol suggests prediabetes, and 48 mmol/mol and greater indicate diabetes.

3.      Fasting Insulin and HOMA-IR Index

This test evaluates insulin sensitivity by assessing both fasting glucose and insulin levels. A high HOMA-IR value confirms insulin resistance may exist even though diabetes has not developed.

4.     Lipid Profile

Insulin resistance is frequently associated with abnormal cholesterol levels – increased triglycerides and decreased HDL (good cholesterol).

These would also be included in a Comprehensive Metabolic Health Screening or Full Body MOT package for providing a complete picture of your health.

Common Conditions and Health Risks

Insulin resistance, when left untreated, may result in serious long-term complications:

• Type 2 diabetes: Persistent insulin resistance will eventually lead to pancreas failure.
• Cardiovascular disease: Due to high cholesterol and chronic inflammation.
• Fatty liver disease (non-alcoholic fatty liver disease or NAFLD): The body will convert excess glucose into fat to be stored in the liver.
• Polycystic ovary syndrome (PCOS): Insulin resistance will lead to persistently irregular ovulation and hormonal dysregulation.
• Hypertension (high blood pressure): Causes metabolic dysfunction.

Detecting insulin resistance as early as possible through routine blood tests allows for proactive management in these areas.

Lifestyle Modifications to Reduce Insulin Resistance

The good news is that insulin resistance can sometimes be reversed – or at least significantly improved – through small, sustainable lifestyle changes.

1. Balanced diet

Choose whole unprocessed foods, cutting back on added sugars and refined carbohydrates. Focus on:

• Lean protein sources, legumes, whole grains, and vegetables.
• Healthy fats like nuts, olive oil and avocado.
• Balancing portions and eating mindfully to avoid food-related spikes in energy level.

2. Regular physical activity

Exercise will increase the body’s insulin sensitivity and work to reduce body fat. You should work towards:

• At least 150 minutes of moderate aerobic activity every week.
• 2 sessions of strength training weekly to help build lean muscle mass and boost metabolism.

3. Stress Management

Prolonged stress can increase cortisol, which can then worsen your hormonal balance and blood sugar regulation. Finding ways to relieve stress and practicing things like mindfulness, meditation, plus sleeping adequately can help.

4. Make Sleep a Priority

Aim for 7 to 9 hours of good quality sleep. Poor sleep is associated with increased insulin resistance and appetite-regulating hormones.

5. Weight Management

A modest reduction in body weight (5 to 10%) could meaningfully improve your insulin sensitivity and disturbances in blood sugar regulation.

Medical Treatment Options

If lifestyle measures are not enough, your GP may recommend treatment options such as:

• Drugs enhancing insulin sensitivity and suppressing hepatic glucose production.
• Lipid lowering agents – if cholesterol is elevated.
• Nutritional supplements: Intake of magnesium, vitamin D, and omega-3 fatty acids to assist with metabolic balance.

All treatments and targeted management should be based on your blood results and clinical history.

Preventing Blood Sugar Imbalance in the Long-Term

Preventative health check-ups are an important aspect of your long-term wellbeing. Regular blood tests allow your physician to track changes before symptoms develop.

At London GP Clinic, we suggest for:

• Individuals over 35 or someone who is identified at risk might want to have annual fasting glucose and HbA1c tests.
• If you have a family history of PCOS or diabetes – for more frequent monitoring.
• Comprehensive health checks including cholesterol screening, blood tests, and body composition analysis.

A proactive approach can protect your metabolic health for the future.

When to Book an Appointment with a Doctor

Book an appointment if you have ongoing tiredness, unusual weight gain, are excessively thirsty, or have a family history of diabetes. Early assessment will ensure that you are managed effectively and prevent an issue occurring.

Our highly experienced doctors at London GP Clinic can offer same-day blood tests with quick results and personalised advice that supports your best health.

Conclusion

Blood sugar imbalance and insulin resistance are both serious but hidden health issues that can lead to diabetes and other chronic health problems, when left unaddressed. Recognising early signs, being mindful of risk factors and making sure you have testing done regularly are all key prevention measures.

London GP Clinic offers assessments of your metabolic health with thorough examinations including HbA1c, fasting glucose, and insulin and lipid testing in a professional and relaxing atmosphere.