General Facts about Obesity


Obesity is defined as “abnormal or excessive fat accumulation that may impair health”.1 With respect to obesity, it is important to understand the term “body mass index” (BMI). The BMI of a person helps in differentiating a normal person from an obese person. The BMI is basically an index of weight (measured in kilograms) for the height (measured in meters) of a person, and is indicated as kg/m2. The World Health Organization’s (WHO) crude measure to consider a person “overweight” is a BMI greater than or equal to 25 kg/m2 ; while a BMI of greater than or equal to 30 kg/m2 is considered “obese”.1 Thus, the terms “obesity” and “overweight” differ, but carry a similar meaning and poor health outcomes.


It is estimated that in 2014, nearly 2 billion adults (18 years and above) were overweight and over half a million were obese.1 Obesity was once considered a problem only in high income countries, however, both overweight and obesity are now increasingly observed in low- and middle-income countries, especially in urban areas.Childhood obesity is now a global epidemic that needs to be addressed seriously since it is more than likely that overweight children will graduate into becoming obese adults.


causes of obesityObesity is generally a consequence of an increased consumption of foods that contain a high calorific value and not being able to expend equal amount of energy through physical activity.2 Children, especially from urban settings, globally, are used to eating from fast food eateries and snacking on foods containing high amount of fat and carbohydrates such as chips, crisps, colas, soft drinks and sweets. They tend to use their gadgets such as television sets, computers, gaming consoles which deprive them of exercise and burning calories. The same can be said of adults who are used to being seated at their offices for up to 10 hours each day. Most use transport for to and fro journeys which once again results in inactivity. Additionally, work stress or boredom has also been implicated in binge eating and weight gain.

Other likely causes include an individual’s genetic inheritance.2 If both parents are obese, it is likely that the offspring would go on to develop obesity. A hormonal imbalance as a result of the absence of leptin, a weight controlling hormone, can also trigger obesity in an individual. Certain medications are invariably associated with weight gain. Oral contraceptives and steroids are common culprits. Others included medications for diabetes, depression, and seizures. It is advisable that counseling for a proper diet and exercise plan is also discussed concurrently with the physician prescribing these medications.

Certain diseases themselves also cause weight gain.2 Hypothyroidism (lack of sufficient thyroid hormone), polycystic ovarian syndrome (affects women’s hormone regulation), insulin resistance (diabetes as a result of improper use of body’s insulin) are common conditions that can result in obesity. Once diagnosed it is imperative to consult a dietician/nutritionist who can chart out how best to keep weight under control.

Health risks associated with obesity
Increase in BMI can pose serious health consequences. Children and young adults are especially vulnerable if signs of weight gain occur. It is now known that adult obesity is a consequence of childhood obesity.3The following conditions are associated with being overweight and obese:

i. Metabolic syndrome: This condition includes a combination of excess weight/body fat and cholesterol levels, increased blood sugar levels, and high blood pressure. The presence of metabolic syndrome in an individual increases the risk for heart disease, diabetes, and stroke.4

ii. Type 2 diabetes: This condition occurs when the body is unable to produce insulin to regulate sugar (glucose).5 Complications of type 2 diabetes include retinopathy (leading to loss of vision), nephropathy (kidney disease), and neuropathy (damage to nerves). Type 2 diabetes can have detrimental effect on the heart leading to heart attacks and stroke.6

iii. Hypertension: High blood pressure is often observed in obese and overweight individuals. Untreated hypertension can cause heart failure and strokes.

iv. Respiratory issues: Obese and overweight individuals have fatty deposits on the neck. This can cause sleep apnea(difficult breathing during sleep), and pulmonary hypertension(increased blood pressure in artery of the lungs).

v. Cancer

vi. Infertlity

vii. Arthritis

viii. Gall bladder disease


PreventionIncreasing global trends of obesity is a matter of grave public health concern. The WHO and the National Institute of Health recommend obese and overweight adults, especially those who have associated disease conditions as listed in the above section, to lose at least 10% of their body weight.

Lifestyle modifications include changes in diet, physical activity and behavior. It is recommended that obese and overweight individuals attend weekly individual or group treatment sessions that encourage such lifestyle changes. Studies suggest that even modest weight loss can carry significant positive effects on long-term health.

Several diets have been identified as beneficial, the Ornish diet, Mediterranean diet, Dash diet, etc. Basically, a diet in low-fat, low salt, and plant, fruits and nut-based diets are recommended. Low fat diets improve cholesterol levels, low carbohydrate diets improve triglycerides, low salt diets reduce risk of high blood pressure, low sugar diets improve blood glucose levels.

Since physical inactivity remains one important aspect of obesity, researchers have estimated that more than 30min/day of exercise can control body weight and at least an hour’s exercise of moderate intensity may be required to lose excess body weight.8 There is evidence that exercise in combination with diet has the greatest impact on weight loss.Significant weight loss in overweight and obese individuals can take from 6 months to a year to observe any significant weight loss.Improvements in health related outcomes become obvious after equivalent of at least 150 min/week of moderate-intensity physical activity as recommended by the Institute of Medicine, American College of Sports Medicine, and the International Associationfor the Study of Obesity. Resistance training can be added to the regime of overweight and obese individuals. This can help in improving muscular strength.

Behaviour therapy techniques at the hands of expert can modify a person’s thinking habit. This can take significance for overweight and obese individuals who need to modify their eating and physical activity habits to a considerable extent when compared to normal weight individuals. Setting achievable target goals, maintaining a record of diet and activityare some techniques that are employed. Many internet-based self-monitoring programmes are available, however the success of these compared to face-face programmes seem limited.7

Weight Watchers, Jenny Craig, and Nutrisystem with options for pre-packaged calorie restricted home delivered meals have become popular. Some studies suggest that weight loss from such commercial ventures could be an option for those obese or overweight individuals who cannot engage with health professionals on a regular long-term basis.7


The U.S. Food and Drug Administration recently (2014, September) approved Contrave, as an anti-obesity medication to be prescribed to those overweight and obese individuals who also have one weight-related disease condition, and are unable to lose weight through diet and exercise, and cannot undergo weight loss surgery.9 Other anti-obesity medications are also available and only available through prescription.

Morbid or extreme obesity combined with serious health issues can be dealt by surgery known as bariatric surgery. The surgery involves by reducing the size of the stomach and bypassing a large portion of the intestines so that food intake affects only a small portion of the intestine. This is followed by a regular follow-up that assesses the patient’s nutritional requirements to avoid nutritional deficiencies. Patients have benefitted from this procedure with adequate weight loss as well as significant improvement in their obesity related health condition. Many are able to discontinue medications that they were taking before surgery for their diseases, and hence a regular follow-up is mandatory.10


Obesity is now considered a global epidemic. There are worldwide campaigns to end obesity since the overall disease burden is a great drain on a nation’s resources. Knowledge of obesity and its consequences is very important to understand at the individual level. Adopting a healthy lifestyle from infancy can prevent weight issues in adulthood. Overweight and obese individuals can also modify their thinking, diet and physical activity and promote weight loss.


  1. Obesity and overweight. Fact sheet N°311. Updated January 2015. Available at: Accessed 04 Feb 2015.
  2. Available at: Accessed on 04-02-2015.
  3. Kopelman P. Health risks associated with overweight and obesity. Obesity reviews. 2007; 8 (Suppl. 1): 13–17.
  4. Available at Accessed 05-02-2015.
  5. (Available at Accessed 05-02-2015.
  6. Grundy SM. et al. AHA Scientific Statement. Diabetes and Cardiovascular Disease. Ciculation. 1999;100: 1134-1146.doi 10.1161/01.CIR.100.10.1134.
  7. Wadden TA, Webb VL, Moran CH, Bailer BA. Obesity. Lifestyle Modification for Obesity. New Developments in Diet, Physical Activity, and Behavior Therapy Circulation.2012; 125:1157-1170.
  8. Jakicic JM, Otto AM.Physical activity considerations for the treatment and prevention of obesity. Am J Clin Nutr 2005;82(suppl): 226S–9S.
  9. Available at: Accessed 06-02-2015.
  10. Available at: Accessed 06-02-2015.
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