Though we can measure weight, it does not denote whether an individual is overweight or not. Measurements like Body Mass Index (BMI), Waist Circumference and Skin fold thickness are more useful.

Eating too many calories and not getting enough physical activity are the main causes of obesity, especially in combination.

Diet: Regular consumption of high-calorie foods, such as fast foods, contributes to weight gain. High-fat foods are dense in calories. Cakes, ice-creams, chocolates, chips, samosas and deep fried food items are high in fat and calories.

Physical Inactivity: Sedentary lifestyle without exercise.

Psychological factors: Some people overeat to cope with problems or deal with emotional stress.

Genetics: If one or both of your parents are obese, your chances of being overweight are greater. But, your genetic makeup doesn't always guarantee that you'll be obese.

Age: As you get older, you tend to be less active. In addition, the amount of muscle in your body tends to decrease with age. This lower muscle mass leads to reduction in calorie expenditure. If one doesn't decrease calorie intake as they become older, they are likely to gain weight.

Pregnancy: During pregnancy a woman's weight increases naturally. Some women find this weight difficult to lose after the baby is born. This weight gain may contribute to the development of obesity in women.

Medications: Inappropriate steroid and antidepressant medication use can occasionally lead to obesity.

Medical problems: Hormonal disorders like Cushing's syndrome can cause weight gain. A medical problem, such as arthritis, can also lead to decreased activity, which can result in weight gain.

Alcohol: Drinking alcohol adds calories to your diet — just one regular beer is about 150 calories. If you don't cut back somewhere else, adding just one beer daily could cause a weight gain of more than one pound a month. Additionally, excessive drinking can stimulate your appetite and make you eat more.

Body mass index (BMI). The BMI is a formula that uses weight and height to estimate body fat and health risks. If your BMI is between 19 and 23 (for Indians), you're considered in a healthy weight range for your height. If your BMI is between 24 and 29, you're considered overweight. Consult your doctor if you are overweight or obese.

Waist circumference. If you carry most of your fat around your waist or upper body, you may be referred to as apple shaped. If you carry most of your fat around your hips and thighs or lower body, you may be referred to as pear shaped. Being apple shaped increases your risk of many of the serious conditions associated with obesity. Women's waist measurements should be less than 80 cms. Men's should be less than 90 cms. This has been purposefully lowered in Indians due to the increased risk of diabetes and heart disease early on compared to westerners. If you have a large waist circumference, talk to your doctor about weight loss.

Talking to your doctor openly and honestly about your weight is one of the best things you can do for your health. The more your weight increases, the more medical problems you may have to face. Also, talk to your doctor if you have weight-related medical conditions, such as high blood pressure, high blood cholesterol, diabetes and arthritis. These health conditions may improve if you're able to lose weight.

If you're obese, you're more likely to develop a number of potentially serious health problems. These may include:

• High blood pressure
• Diabetes
• Abnormal cholesterol.
• Heart disease/Heart attack
• Stroke/Paralysis
• Osteoarthritis (wear and tear of joints)
• Sleep apnoea (interrupted breathing during sleep)
• Cancer (colon cancer, uterine cancer, breast cancer)
• Fatty liver disease (fat in the liver, inflammation of liver)
• Gallstones

Emotional problems like depression, feeling isolated and rejected are also linked to obesity. This can lead to further isolation, discrimination at work, school and social settings.

The treatment of obesity needs to be long-term and not short-term. Weight loss should be gradual and vigilant follow-up is necessary to prevent rebound weight gain. Behaviour and lifestyle changes are the most important ways for a successful weight loss program. These changes focus on gradual, permanent changes in eating and exercise habits.

There are four simple ways one can change behaviour and lifestyle that will help maintain weight loss:

• Learning about nutrition
• Changing eating habits
• Increasing your physical activity
• Changing your attitudes about eating

Drugs and surgery are for those who have failed to reduce weight despite effective changes in their lifestyle.

To lose weight and keep it off, eat moderate amounts of nutrient-rich, low-fat, low-calorie foods. Follow these fundamentals of healthy eating:

• Think 'energy density.' Oils and butter are dense with calories, so we take more to satisfy our hunger thereby resulting in high calories intake.
• Choose healthy foods. Healthy foods include vegetables, fruits and grains. These foods optimize nutrition, taste and promote a healthy weight.
• Choose the right carbohydrates. Steer away from simple carbohydrates, such as refined sugar and limit fruit juices.
• Cut back on sweets. Limit intake of cakes, cookies, ice creams, chocolates. They're a large source of calories.
• Reduce fat (oils, deep fried food items, non-vegetarian foods like meat)

Another way to lose weight is to increase physical activity.

A few minutes of walking or stair climbing can be as good as structured exercise. Walking, jogging, and cycling for a period of 30 – 60 min for at least 5 days a week is good for health.

Here are some other simple ways to add more activity to your day:

• Take the stairs — not the elevator.
• Short walk during lunch hour.
• Play with your children instead of watching them play.
• Walk with your family after dinner.
• Buy an exercise bike and pedal while watching TV.

Drugs are useful for people who are unable to lose weight despite strict dietary restriction and regular activity. Sometimes it is useful in people with disabilities which prevent them from physical exercise. The commonly used weight loss medication currently in use is Orlistat. It is very safe but treatment should be under a specialist with experience in using these medications on a regular basis

Another treatment option for severe obesity is bariatric surgery. Surgery should be only considered in patients who fail to lose weight by lifestyle measures or if a person has an obesity-related disease. Surgery should only be done at centres with specialist surgeons and physicians committed to long-term follow-up. The surgery for obesity (bariatric surgery) is done with the principle aim to reduce the size of the stomach or by altering the digestive process, which promotes weight loss. There are multiple procedure and the risk of procedure is very low in skilled hands. But it is not an answer to a lazy or sedentary lifestyle.