By Renova Hospitals
January 06, 2026
Obesity: Causes, Health Risks, Diagnosis, and Treatment Options
Overview
Obesity is a chronic, complex medical disease defined by excessive accumulation of body fat that harms overall health. It is most commonly identified using body mass index, where a BMI of 30 or above is considered obesity in adults.
Modern medicine recognizes obesity not as a cosmetic issue, but as a condition driven by metabolism, genetics, hormones, environment, and behavior.
Modern medicine recognizes obesity not as a cosmetic issue, but as a condition driven by metabolism, genetics, hormones, environment, and behavior.
In India, obesity has become one of the fastest-growing health challenges across all age groups. Sedentary lifestyles, long working hours, high-calorie processed foods, stress, poor sleep, and limited physical activity have contributed to a rising obesity rate in India.
Without early medical intervention, obesity often progresses silently and leads to serious long-term complications.
Obesity can cause health problems throughout your body
Obesity affects nearly every organ system in the body. Excess fat tissue increases inflammation, alters blood flow, and disrupts normal metabolic function. Over time, these changes raise the risk of diabetes, heart disease, stroke, and organ damage.
The impact of obesity is not limited to internal organs. Physical endurance decreases, fatigue increases, and mobility becomes restricted. These changes reduce quality of life and independence.
Obesity has direct and indirect effects on many body systems
Direct effects of obesity occur due to physical stress from excess weight. Joints, spine, and muscles bear increased load, leading to pain and early degeneration. The lungs and diaphragm also face restriction, causing breathlessness and sleep disorders.
Indirect effects occur through obesity and hormones. Fat tissue acts as an endocrine organ, releasing hormones and inflammatory chemicals that disturb insulin, leptin, estrogen, testosterone, and cortisol. These hormonal changes increase appetite, slow metabolism, and promote further fat storage.
What is obesity?
Obesity is defined as abnormal or excessive fat accumulation that presents a health risk. It is a chronic disease that often develops gradually over many years. Once established, the body adapts to the higher weight and actively resists weight loss.
Obesity also affects emotional and psychological health. Stigma, low self-esteem, anxiety, and depression are common. Medical treatment focuses on restoring health, not blaming individuals.
Symptoms and Causes
What are the symptoms of obesity?
Obesity does not usually present with a single obvious symptom. Many individuals feel “normal” despite having significant health risks. Diagnosis relies on measurements and associated medical conditions.
Healthcare providers assess obesity using:
- Body mass index (BMI)
- Waist circumference
- Body fat distribution
- Presence of obesity-related disorders
Body mass index (BMI)
BMI compares body weight to height and provides an estimate of body fat. It is widely used because it is simple and standardized. However, BMI does not directly measure fat mass.
People with high muscle mass may have elevated BMI without excess fat. Others may have normal BMI but high visceral fat. Doctors therefore interpret BMI alongside other clinical findings.
BMI classifications
BMI is used to define obesity categories, which help guide treatment decisions and risk assessment.
- Class I obesity: BMI 30–34.9
- Class II obesity: BMI 35–39.9
- Class III obesity: BMI ≥40
As obesity class increases, the risk of diabetes, heart disease, infertility, and early mortality rises significantly.
Waist circumference
Waist circumference measures abdominal or visceral fat, which is especially dangerous. Visceral fat surrounds vital organs and releases inflammatory substances. It strongly predicts cardiovascular disease and diabetes risk.
Abdominal obesity is closely linked to obesity and hormones, particularly insulin resistance and cortisol imbalance. This explains why belly fat carries higher risk than fat in hips or thighs.
What causes obesity?
At its core, obesity occurs when calorie intake exceeds energy expenditure over time. However, this imbalance is driven by complex biological, environmental, and psychological factors. Obesity is rarely caused by lack of willpower alone.
Major contributing factors include:
- High intake of ultra-processed, calorie-dense foods
- Sugary drinks and frequent snacking
- Sedentary lifestyle and prolonged screen time
- Poor sleep disrupting hunger hormones
- Chronic stress triggering emotional eating
- Certain medications such as steroids and antidepressants
Hormonal and reproductive conditions also play a role. Disorders like thyroid imbalance and pcos and obesity are strongly linked due to insulin resistance and hormonal disruption.
What are the complications of obesity?
Obesity causes both metabolic and mechanical complications. Many develop silently and worsen over time. Early intervention can prevent or reverse several of these effects.
Metabolic changes
As fat cells enlarge, they release inflammatory chemicals that interfere with insulin action. This leads to insulin resistance, abnormal cholesterol levels, and rising blood sugar. Blood pressure also increases.
Metabolic complications include:
- Type 2 diabetes
- Hypertension
- Dyslipidemia
- Metabolic syndrome
These conditions significantly increase cardiovascular risk.
Direct effects
Excess weight physically strains the body. Joints, spine, and respiratory muscles are affected. Mobility decreases and daily activities become difficult.
Direct complications include:
- Osteoarthritis and joint degeneration
- Chronic back and neck pain
- Obstructive sleep apnea
- Obesity hypoventilation syndrome
Obesity also increases the risk of certain cancers, depression, and cognitive decline.
Diagnosis and Tests
How do healthcare providers diagnose obesity?
Diagnosis begins with accurate measurement of height, weight, and waist circumference. BMI is calculated and classified. Body fat distribution is assessed.
Healthcare providers also evaluate:
- Medical history and medications
- Family history of obesity-related diseases
- Dietary habits and physical activity levels
- Sleep patterns and stress levels
Blood tests may assess glucose levels, cholesterol, liver enzymes, thyroid function, and reproductive hormones. This complete evaluation allows personalized treatment planning.
Management and Treatment
How is obesity treated?
There is no single permanent obesity cure. Obesity management focuses on long-term weight control, metabolic improvement, and prevention of complications. Treatment plans are individualized and adaptive.
Management usually involves:
- Nutrition therapy
- Physical activity planning
- Behavioral and mental health support
- Medications or surgery when appropriate
Long-term follow-up is essential for success.
Changing what you eat
Nutrition therapy focuses on sustainable eating habits rather than extreme dieting. Balanced meals stabilize blood sugar and reduce hunger. Proper nutrition supports hormonal balance.
Doctors may recommend:
- Mediterranean diet
- DASH diet
- High-fiber, low-glycemic meal plans
These approaches are evidence-based and easier to maintain long term.
Building activity into your day
Physical activity improves insulin sensitivity, heart health, and mood. It also preserves muscle mass during weight loss. Even moderate activity offers meaningful benefits.
Recommended strategies include:
- Daily walking
- Strength training
- Reducing prolonged sitting
Activity plans are customized based on age, joint health, and fitness level.
Mental health support
Stress, anxiety, and depression strongly influence eating behavior. Emotional eating is common in obesity. Mental health support improves long-term outcomes.
Support may include:
- Counseling or psychotherapy
- Cognitive behavioral therapy
- Sleep optimization and stress management
Medication for weight loss
Weight-loss medications may be prescribed when lifestyle changes alone are insufficient. These medications act on appetite regulation and satiety pathways. Medical supervision is mandatory.
Medications support weight loss but do not replace healthy habits. Regular monitoring ensures safety and effectiveness.
Weight loss surgery
Obesity surgery may be recommended for severe obesity or obesity with serious medical complications. Surgery alters digestion and hunger hormones. It often leads to significant and sustained weight loss.
Common procedures include:
- Gastric sleeve
- Gastric bypass
- Duodenal switch
Surgery requires lifelong nutritional monitoring and follow-up care.
Outlook / Prognosis
What can I expect if I have obesity?
Obesity increases the risk of many chronic diseases. However, meaningful improvement is possible with treatment. Even modest weight loss of 5–10% improves blood sugar, blood pressure, and cholesterol.
Obesity is a long-term condition requiring ongoing care. Early treatment improves prognosis. Consistency is key.
Prevention
Can obesity be prevented?
Prevention focuses on early lifestyle habits and awareness. Small, consistent changes reduce long-term risk. Prevention is easier than treatment.
Key precautions of obesity include:
- Balanced meals and portion control
- Regular physical activity
- Adequate sleep
- Stress management
Preventive strategies reduce disease burden significantly.
Additional Common Questions
What can I do to avoid regaining lost weight?
Weight regain is common without long-term planning. Obesity requires continuous management. Maintenance is an active process.
Effective strategies include:
- Regular medical follow-up
- Continued physical activity
- Structured meal planning
Obesity, fertility, and women’s health
Obesity disrupts reproductive hormones and ovulation. Obesity infertility is linked to insulin resistance and hormonal imbalance. Weight loss improves fertility outcomes.
Conditions such as pcos and obesity often coexist and worsen each other. Weight management improves menstrual regularity and insulin sensitivity. Medical guidance ensures safe outcomes.
Obesity Is Treatable With the Right Medical Guidance
At Renova Hospitals, obesity is treated as a medical disease, not a personal failure. Our multidisciplinary teams address metabolism, obesity and hormones, mental health, and long-term sustainability. Care is personalized, evidence-based, and compassionate.
If you are concerned about weight or related health issues, seek medical guidance early. Timely care can prevent complications and improve quality of life. You are not alone, and effective help is available.
