Did you know that obesity is now considered a chronic disease [1], not just a lifestyle problem? Every day, millions of people silently carry not just excess weight, but also shame, judgment, and guilt. They are told to “just eat less” or “move more”, but the causes of obesity and what really works are not that simple.
Dr. Sarthak Chakarvarthy, Consultant Physician at TATA 1mg, states that “Doctors are treating obesity as a medical condition that sometimes needs medical treatment. Emerging anti-obesity drugs can offer hope.”
This World Obesity Day, it’s important to pause and look at “8 billion reasons to act on obesity”, which is the theme for this year [2]. The message is simple yet powerful — with the world’s population now crossing 8 billion, every single life matters. Obesity affects people across age groups, geographies, and income levels. Acting on obesity is not just about individual health — it is about protecting global health. Because for many people, it isn’t about laziness or lack of willpower. It’s biology, hormones, genetics, and environment. Let’s understand more.
Obesity Is More Than A Number On the Scale
According to the World Health Organization (WHO), obesity is defined as abnormal or excessive fat accumulation that presents a health risk [1]. It is classified as a chronic, complex disease influenced by genetic, metabolic, behavioural, and environmental factors.
Obesity is defined using Body Mass Index (BMI), but health risks go far beyond a calculation. Excess body fat, mainly around the abdomen, increases the risk of [3]:
– Type 2 diabetes
– Heart disease
– High blood pressure
– Fatty liver disease
– Joint problems (gout or osteoarthritis)
– Sleep apnea
– Certain cancers
But what is often overlooked is the emotional toll, anxiety, low self-esteem, social stigma, and constant dieting cycles. Obesity affects physical and mental health together. This increases the chances of developing depression, eating disorders, and similar conditions.
Read the signs of eating disorders beforehand and stay alert!
The theme “8 Billion Reasons to Act” highlights that obesity is not a niche problem—it affects families, healthcare systems, and economies worldwide. With over 8 billion people on the planet, rising obesity rates increase the burden of other health issues. Acting early means reducing preventable disease and protecting millions of lives.
Understanding BMI: Where Do You Fall?
Body Mass Index (BMI) is a screening tool used to classify weight status.
Standard World Health Organization (WHO) classifications are [4]:
– Normal weight: 18.5 – 24.9 kg/m²
– Overweight: 25 – 29.9 kg/m²
– Obese: 30 kg/m² and above
Asian/Indian Cut-offs (More Sensitive to Risk) [4]:
– Normal weight: 18.5 – 22.9 kg/m²
– Overweight: 23 – 24.9 kg/m²
– Obese: 25 kg/m² and above
For Indian populations, health risks like diabetes and heart disease may begin at lower BMI levels. That’s why doctors often use the Asian cut-offs. However, BMI does not measure body fat distribution. Waist circumference and metabolic markers are equally important.
What Are Some Common Causes of Obesity
Obesity develops from multiple overlapping factors — not just overeating.
1. Genetic Predisposition
Some individuals are biologically more prone to weight gain and fat storage.
2. Sedentary Lifestyle
Long work hours, screen time, and reduced physical movement can significantly lower calorie expenditure.
3. Ultra-Processed Diets
High intake of refined carbs, sugary beverages, fried snacks, and packaged foods contributes to excess calorie intake.
4. Poor Sleep
Chronic sleep deprivation can increase hunger hormones and reduce satiety signals.
5. Hormonal Imbalances
Conditions such as hypothyroidism, PCOS, and insulin resistance can influence weight.
6. Stress
Chronic stress elevates cortisol, which may promote abdominal fat accumulation.
7. Environmental and Social Factors
Easy access to calorie-dense food and limited access to safe spaces for physical activity also play a role.
What Should You Do If You’re Struggling With Weight?
If you are someone who is struggling with weight, you should:
– Avoid crash diets
– Get your blood sugar, thyroid, and metabolic markers checked
– Speak to a doctor if BMI is in the overweight or obese range
– Ask whether medication is appropriate — don’t assume
– Focus on long-term health, not just appearance
The Rise of GLP-1-Based Anti-Obesity Medications
In recent years, a class of medications known as GLP-1 receptor agonists, including semaglutide, has changed the conversation. Originally developed for type 2 diabetes, these medications were found to support weight reduction significantly.
How do they work?
GLP-1 is a hormone naturally released in the gut after eating. It helps regulate appetite and blood sugar. When used as medication, GLP-1 receptor agonists may [5]:
- Reduce hunger signals in the brain
- Increase feelings of fullness
- Slow gastric emptying
- Improve blood sugar control
As a result, people tend to eat less — not by force, but because appetite itself is reduced. Heard about food noise – it’s something many patients can relate to. The constant thoughts about eating, strong cravings, and difficulty feeling satisfied. For some, GLP-1 medications quiet that internal struggle.
If you don’t know about ‘Food Noise’, just click to know more.
Who Are These GLP-1 Medications For?
GLP-1-based treatments are not cosmetic tools. They are prescribed for individuals who have a BMI ≥ 30 or BMI ≥ 27 with obesity-related conditions like diabetes, etc. However, regular monitoring is still required, and dosages need to be adjusted gradually. Though lifestyle guidance continues, self-medication or using these drugs without medical supervision can be risky.
Are They Safe?
Like all medications, GLP-1 receptor agonists have side effects. Common ones include nausea, vomiting, diarrhea or constipation, and reduced appetite. Most side effects are mild and improve over time. However, they are not suitable for everyone. A thorough medical evaluation is necessary before starting treatment.
To start with, speak to a professional guide or doctor today!
Long-term safety data is still expanding, and doctors weigh benefits versus risks carefully. This is not a trend-driven decision; it’s a clinical one.
Dr. Sarthak adds that, although GLP-1-based medications have shown promising results, prevention through diet, movement, and systemic changes remains essential.
Lifestyle Still Comes First
Before medications are even considered to reduce the causes of obesity, foundational habits can include:
– Nutrition: Balanced meals with adequate protein, fiber, and controlled portions that can improve insulin sensitivity. Reducing ultra-processed foods and sugary drinks can make a measurable difference.
– Movement: Regular physical activity, especially strength training combined with moderate cardio, can support metabolic health.
– Sleep and Stress: Chronic sleep deprivation and stress can increase cortisol levels and disrupt appetite regulation.
These lifestyle changes aren’t optional. They remain central to obesity management, but for some people, lifestyle efforts alone are not enough.
What About Surgery?
For individuals with severe obesity or obesity with serious complications, bariatric surgery remains an option. It works by altering gut hormones, appetite signals, and nutrient absorption. Surgery and medication are not competing tools — they are part of a spectrum of medical care. The right choice depends on individual health status.
The Way Forward: Compassion Over Criticism
World Obesity Day is not about promoting weight loss fads. It is about awareness and understanding what the causes of obesity are and what you can really do. Obesity deserves medical attention, just like hypertension or diabetes.
FAQs
Q. What are the causes of obesity in India?
The causes of obesity are:
– Sedentary lifestyles
– High intake of ultra-processed foods
– Sugary beverages
– Poor sleep
– Stress
– Genetic predisposition
– Hormonal conditions like PCOS or hypothyroidism
Q. What are some of the risks involved with obesity?
Obesity increases the risk of type 2 diabetes, high blood pressure, heart disease, fatty liver, and certain cancers. It can also develop joint problems or sleep apnea.
Q. Can obesity be reversed?
Yes, weight reduction and metabolic improvement are possible with sustained lifestyle changes, medical support, and, in some cases, medications or surgery. Early intervention works best.
Q. What is the biggest indicator of obesity?
Body Mass Index (BMI) is commonly used, but waist circumference is also an important indicator, especially for abdominal fat.
Q. Which cancers are caused by obesity?
Obesity is linked to a higher risk of breast (postmenopausal), colorectal, endometrial, pancreatic, kidney, and liver cancers [2].
Q. What are the four pillars of good and balanced health?
The four pillars of optimised health are balanced nutrition, regular physical activity, adequate sleep, and stress management.
Q. What weight is considered dangerously obese?
A BMI of 30 or above is considered obese, and 40 or above is classified as severe or morbid obesity. The higher the BMI, the higher the health risks.
Q. What blood tests are done for obesity?
For obesity, doctors may check fasting blood sugar, HbA1c, lipid profile, thyroid function, and liver function. Sometimes insulin levels are also checked for metabolic health. All these tests are usually done or recommended for obesity.
References
1. World Health Organization: WHO. Obesity and overweight. https://www.who.int/news-room/fact-sheets/detail/obesity-and-overweight. Published December 8, 2025.
2. May T. World Obesity Day 2026: 8 Billion Reasons to Act on Obesity. Research Communities by Springer Nature. https://communities.springernature.com/posts/world-obesity-day-2026-8-billion-reasons-to-act-on-obesity. Published March 5, 2026.
3. Health Risks of Overweight & Obesity. National Institute of Diabetes and Digestive and Kidney Diseases. https://www.niddk.nih.gov/health-information/weight-management/adult-overweight-obesity/health-risks. Published October 7, 2025.
4. Singh S, Sikri G, Garg M. Body Mass Index and Obesity : Tailoring “cut-off” for an Asian Indian Male Population. Medical Journal Armed Forces India. 2008;64(4):350-353. doi:10.1016/s0377-1237(08)80019-6
5. Popoviciu MS, Păduraru L, Yahya G, Metwally K, Cavalu S. Emerging role of GLP-1 agonists in obesity: A Comprehensive review of randomised controlled trials. International Journal of Molecular Sciences. 2023;24(13):10449. doi:10.3390/ijms241310449
(The article is written by Sneha Jajoo, Intern, Clinical Health & Content, and is reviewed by Dr.Subita Alagh, Assistant Team Lead, Disease Content.)