Op.Dr.Gökhan ATEŞ — Antalya Obezite CerrahisiOp.Dr.Gökhan ATEŞ
Patient Education

What Is Obesity? Causes and Health Effects

Obesity is defined as abnormal or excessive fat accumulation that presents a risk to health. It is not merely an aesthetic issue; it is a major risk factor for type 2 diabetes, hypertension, cardiovascular disease, and certain cancers.

Medical Definition

The World Health Organization defines obesity as a BMI of 30 or above. Class II obesity begins at 35, and class III (severe) obesity at 40. Waist circumference (≥102 cm in men, ≥88 cm in women) is an additional metabolic risk indicator.

Main Causes

Genetic and epigenetic predisposition

High-calorie, ultra-processed diets

Sedentary lifestyle

Sleep irregularity and chronic stress

Hormonal disorders (hypothyroidism, Cushing's syndrome)

Side effects of some medications

Psychosocial factors (eating disorders, depression)

Associated Conditions

Type 2 diabetes and insulin resistance

Hypertension and cardiovascular disease

Obstructive sleep apnoea

Non-alcoholic fatty liver disease (NAFLD)

Joint pain and osteoarthritis

Polycystic ovary syndrome and infertility

Certain cancers (breast, colon, endometrium)

Why It Matters

Obesity is a treatable chronic disease. Early diagnosis, lifestyle modification, medical therapy when appropriate, and bariatric surgery in suitable patients can substantially improve long-term health outcomes.

References

  • World Health Organization — Obesity and overweight fact sheet
  • International Diabetes Federation — Metabolic Syndrome Criteria
Medical notice: The information on this page is for general patient education only and does not replace medical diagnosis, treatment, or a surgical decision. The appropriate method for you can only be determined after a physician's assessment and necessary tests.

Last updated: 28.06.2026 · Medical content: Op.Dr.Gökhan ATEŞ

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