Overweight and Obesity: The Silent Threat Leading to Diabetes

Overweight and obesity not only affect body shape but are also leading causes of diabetes. This close relationship is often overlooked, but understanding the impact of body weight on blood glucose is important for taking proactive steps to protect your health. This article will help you recognize this “silent enemy” and learn about effective preventive measures.

1. Did You Know? Overweight and Obesity Are Major Risk Factors for Diabetes

1.1. How to Recognize Overweight and Obesity

Overweight and obesity are conditions characterized by abnormal or excessive accumulation of body fat, which can negatively affect health and increase the risk of chronic diseases such as type 2 diabetes, hypertension, and cardiovascular disease [1, 6].

Body Mass Index (BMI) is used to assess these conditions. BMI is calculated by dividing body weight (kg) by the square of height (m). For example, if you weigh 60 kg and are 1.6 m tall, your BMI is 60 / (1.6 × 1.6) ≈ 23.4 kg/m².

Due to differences in body composition, Asian populations tend to face health risks at lower body weights compared with Western populations. Therefore, the BMI thresholds used for assessment are also stricter: overweight is defined as a BMI of ≥23.0 kg/m², while obesity is defined as a BMI of ≥25.0 kg/m².

1.2. Why Does Obesity Increase the Risk of Diabetes?

The link between obesity and type 2 diabetes has been well established: most people with type 2 diabetes are overweight or obese [1, 3, 5]. Among the various factors involved, abdominal obesity (visceral fat) plays a central role in the pathogenesis through the following mechanisms:

Insulin Resistance: The Core Mechanism

Insulin acts as a key that helps glucose move from the bloodstream into cells to produce energy. In people with obesity, cells, particularly those in the muscles and liver, become “resistant” or less sensitive to insulin [4, 5]. To compensate, the pancreas has to work harder to produce more insulin. When this compensatory capacity is exceeded, pancreatic function declines, leading to chronic hyperglycemia [1, 4].

The Negative Effects of Excess Adipose Tissue

Adipose tissue, particularly visceral fat, is not simply an energy storage site but also functions as an active endocrine organ:

• Releases free fatty acids: Directly interferes with the transport of glucose into cells.
• Secretes inflammatory substances: Promotes chronic inflammation, which further worsens insulin resistance.

Impaired Pancreatic Function

The prolonged demand to produce large amounts of insulin places stress on the insulin-producing cells of the pancreas, causing them to become damaged and gradually die over time. When the function of these cells declines significantly, type 2 diabetes develops [1, 5].

1.3. Warning “Signals” and Dangerous Complications

Early Warning Signs of Diabetes

Type 2 diabetes often progresses silently. Pay attention to symptoms such as [4]:

• Persistent fatigue and unexplained lethargy.
• Constant thirst and frequent urination, especially at night.
• Increased hunger and eating more than usual, with possible unintentional weight loss.
• Minor wounds that heal slowly or recurrent skin infections.
• Reduced visual acuity or blurred vision.

Dangerous Complications

If not properly controlled, obesity and diabetes can create a “double blow” to the body, leading to complications [2, 6]:

• Cardiovascular system: Stroke, myocardial infarction, and atherosclerosis.
• Kidneys: End-stage kidney disease requiring hemodialysis.
• Eyes: Retinal damage that can lead to blindness.
• Nervous system: Numbness and loss of sensation in the hands and feet, increasing the risk of ulcers and limb amputation.
• Liver: Fatty liver disease or cirrhosis.

1.4. When Should You Seek Medical Evaluation and Diagnosis?

Early detection is very important for preventing and managing diabetes. You should have regular health check-ups, especially if you have any of the following risk factors:

• BMI: ≥23.0 kg/m² for Asian populations or ≥25.0 kg/m² for Western populations [2].
• Waist circumference: ≥90 cm for men or ≥80 cm for women [2].
• A family history of diabetes, physical inactivity, or conditions such as hypertension, dyslipidemia, or polycystic ovary syndrome [4, 5].
• A previous diagnosis of prediabetes [5].

Doctors diagnose diabetes through blood tests such as fasting blood glucose testing (after fasting for at least 8 hours) or the HbA1c test, which indicates average blood glucose levels over the past 3 months [4].

1.5. Weight Management – A Key Strategy for Diabetes Prevention

Weight management is one of the most effective ways to prevent and manage type 2 diabetes if you are overweight or obese. Even modest weight loss (5–10% of body weight) can provide significant benefits in improving blood glucose control and reducing cardiovascular risk [5, 10].

A Healthy Diet

• Eat a balanced diet: Prioritize vegetables, fruits, whole grains, and healthy fats [2].
• Limit: Sugar, processed foods, fast food, sweets, carbonated soft drinks, and high-fat foods [2].
• Stay hydrated: Water is a good choice to support the body's metabolic processes.

Appropriate Physical Activity

Exercise is an important part of achieving a healthy weight and improving insulin sensitivity [12]. It is recommended to engage in at least 150 minutes of moderate-intensity exercise per week, such as brisk walking or swimming, combined with strength-training exercises [12]. At the same time, you should avoid sitting for prolonged periods.

Sleep and Stress Management

Insufficient sleep and prolonged stress can affect hormones and metabolic processes, contributing to weight gain and insulin resistance. Aim for 7–9 hours of sleep each night and manage stress effectively to support weight management.

2. Frequently Asked Questions (FAQ)

• Does obesity inevitably lead to diabetes? Not everyone with obesity develops diabetes, but obesity significantly increases the risk of diabetes [1, 2]. Genetic factors and lifestyle also play important roles [3, 4].
• How much exercise is enough to prevent obesity-related diabetes? At least 150 minutes of moderate-intensity physical activity per week is recommended [12]. Start gradually and progressively increase the intensity.
• Can people who are thin develop type 2 diabetes? Yes. Thin people can still develop type 2 diabetes due to genetic factors or because they may have a high amount of visceral fat despite appearing thin externally [3, 4].

3. Medical Review and References

Medical consultation:

• Nurse Le Thi Thu Ngan – Endocrinology Department, University Medical Center Ho Chi Minh City

References:

• [1] Al-Goblan, A. S., Al-Alfi, M. A., & Khan, M. Z. (2014). Mechanism linking diabetes mellitus and obesity. Diabetes, Metabolic Syndrome and Obesity: Targets and Therapy, 7, 587–591. https://pmc.ncbi.nlm.nih.gov/articles/PMC4259868/. Truy cập: 2026-01-12.

• [2] Chandrasekaran, P., & Weiskirchen, R. (2024). The Role of Obesity in Type 2 Diabetes Mellitus—An Overview. International Journal of Molecular Sciences, 25(3), 1882. https://pmc.ncbi.nlm.nih.gov/articles/PMC10855901/. Truy cập: 2026-01-12.

• [3] Chadt, A., Scherneck, S., Joost, H.-G., & Al-Hasani, H. (2018). Molecular links between Obesity and Diabetes: “Diabesity”. In Endotext. MDText.com, Inc. https://www.ncbi.nlm.nih.gov/books/NBK279051/. Truy cập: 2026-01-12.

• [4] Banday, M. Z., Sameer, A. S., & Nissar, S. (2020). Pathophysiology of diabetes: An overview. Avicenna Journal of Medicine, 10(4), 174–188. https://pmc.ncbi.nlm.nih.gov/articles/PMC7791288/. Truy cập: 2026-01-12.

• [5] Klein, S., Gastaldelli, A., Yki-Järvinen, H., & Scherer, P. E. (2022). Why Does Obesity Cause Diabetes? Cell Metabolism, 34(1), 11–20. https://pmc.ncbi.nlm.nih.gov/articles/PMC8740746/. Truy cập: 2026-01-12.

• [6] Lin, X., & Li, H. (2021). Obesity: Epidemiology, pathophysiology, and therapeutics. Frontiers in Endocrinology, 12, 706978. https://doi.org/10.3389/fendo.2021.706978. Truy cập: 2026-01-12.

• [10] Wing, R. R., Lang, W., Wadden, T. A., Safford, M., Knowler, W. C., Bertoni, A. G., Hill, J. O., Brancati, F. L., Peters, A., & Wagenknecht, L. (2011). Benefits of modest weight loss in improving cardiovascular risk factors in overweight and obese individuals with type 2 diabetes. Diabetes Care, 34(7), 1481–1486. https://doi.org/10.2337/dc10-2415. Truy cập: 2026-01-12.

• [11] Jastreboff, A. M., Aronne, L. J., Ahmad, N. N., Wharton, S., Connery, L., Alves, B., Kiyosue, A., Zhang, S., Liu, B., Bunck, M. C., & others. (2022). Tirzepatide once weekly for the treatment of obesity. New England Journal of Medicine, 387(3), 205–216. https://doi.org/10.1056/NEJMoa2206038. Truy cập: 2026-01-12.

• [12] Poirier, P., & Després, J. P. (2001). Exercise in weight management of obesity. Cardiology Clinics, 19(3), 459–470. https://doi.org/10.1016/S0733-8651(05)70229-0. Truy cập: 2026-01-12.

The information above is for reference purposes only and is not intended as medical advice. Please contact your doctor for detailed medical consultation.