Q: When is a person considered as obese?
Obesity is based on a person’s Body Mass Index [BMI= weight in kg/height in m2]. In the Indian context, a person with a BMI between 18 and 23.5 is considered of normal weight, with a BMI between 23.5 and 27.5 is considered overweight, and with a BMI of more than 27.5 is considered obese.
Q: Why does one gain weight without any apparent reason?
To enable humans to survive periods of food scarcity, the human body was designed to store energy, which could then be drawn upon in times of famine. This built-in fat storage facility was a critical defence mechanism for our ancestors. During those times, starvation and famine were ever-present dangers to survival and over-consumption and obesity were unheard of. Today, we live in a time of surplus and eat more energy-dense foods. But our body still has a tendency to store reserves. This is known as the ‘thrifty gene hypothesis’.
Further, weight gain or weight loss is determined by the ‘calorie equation’. If you burn as many calories as you take in each day, there is nothing left over for storage in the fat cells and your weight remains constant. But if your calorie-intake exceeds your calorie-expenditure, the extra calories get stored in your body and you gain weight.
Simply put, weight gain occurs when energy intake by an individual exceeds energy expenditure over a period of time. Besides, metabolic disorders and genetic inheritance also impact the incidence and symptoms of obesity to varying degrees.
Q: What are the types of obesity?
There are two types of obesity:
- Android or apple-shaped obesity: In this type, excess fat is primarily stored in the abdominal region. Asians are more prone to central obesity, which in turn, makes them increasingly susceptible to type-2 diabetes and other chronic ailments like high cholesterol and hypertension.
- Gyenoid or pear-shape obesity: In this type, excess fat is accumulated in the hip and thighs. Women are more susceptible to this type.
Q: What causes obesity?
Following is the list of simple reasons for weight gain:
- Growth-related phases like pregnancy and recent childbirth [retaining weight after giving birth is common in women]; childhood and adolescent growth phases too are high-risk periods for obesity to set in
- Ageing: Getting older often involves a gradual weight gain due to changes in activity levels and metabolism
- Hypothyroidism: Inactivity of the thyroid gland can contribute to a gain of only about 7 – 8kg secondary to water retention
- Dietary imbalances: Excessive intake of high-fat foods/high-carbohydrate foods and excessive snacking
- Sedentary lifestyle, reduced exercise or activity level
- Reaction to prior dieting: Weight lost by fad diets and extreme methods comes back with a vengeance and is known as rebound weight gain
- Emotional causes like comfort eating and stress eating
- Depressive disorders: Some people eat more with depression or depressive disorders [whereas some people eat less and lose weight instead]
- Compulsive eating disorder [frequent episodes of uncontrolled eating or binge eating]
- Genetic tendency to obesity
- Water retention: Your body may be retaining fluid, which usually is due to ongoing medications like steroids, cyproheptadine, lithium, tranquilisers, phenothiazines, and some antidepressants.
Q: What are the problems associated with morbid obesity?
Obesity and diabetes are twin diseases with the risk of diabetes becoming higher with increase in body fat content. By 2025, India will be home to more than 170 million diabetics. Heart problems, high blood pressure, high cholesterol, sleep apnoea, gastric reflux disease [abnormal reflux of stomach acid], joint pains, deep vein thrombosis [formation of blood clot in a deep vain], infertility, PCOD [polycystic ovary disease], psychological problems, depression and social discrimination are various other problems, which are a direct result of obesity.
Q: How is obesity treated?
The modalities of treatment include:
- Diet and exercise: These form the cornerstone of therapy for people who are overweight.
- Medications: Medications are an adjunct to lifestyle modifications. However, they are not a replacement for the same and should not be considered as a shortcut to losing weight.
- Intragastric balloon insertion: This is a non-surgical procedure in which a saline-filled silicon balloon is inserted into the stomach endoscopically. The balloon acts on the principle of restriction of food intake and early satiety. It is a temporary measure and needs to be removed after six months. It is good for people who want to lose 12 – 15kg weight.
- Bariatric surgery: Improvement in obesity-related diseases is not sustained if weight is regained. It is seen that up to 98 per cent of people fail to maintain weight loss with diet and exercise or medication alone. According to the National Institutes of Health [NIH] conference in 1991, “surgery is the only proven method of long-term sustained weight loss for the patient with severe clinical obesity”.
Surgery is recommended for people with Body Mass Index [BMI] of 35 or above, BMI of 32 – 37 with health problems like diabetes, high blood pressure and heart problems and Multiple failed dietary attempts to lose weight.
Q: What does bariatric surgery involve?
There are two basic types of bariatric surgery: Restrictive and Malabsorptive.
Restrictive mainly consists of the gastric band and sleeve gastrectomy. In the banding procedure, an inflatable silicon band is placed around the upper part of the stomach, which restricts the food intake. It leads to about 50 per cent weight loss. Since results of banding have not been too great, it has slowly gone out of favour.
Sleeve gastrectomy has become much more popular over the last few years. In this surgery, two thirds of the stomach is surgically removed using staplers. This reduces the food intake and takes away the hunger inducing hormone, ghrelin, leading to loss of appetite. This leads to about 75 – 80 per cent weight loss over 18 – 24 months.
Sleeve gastrectomy can also be done through a single incision through the navel. This procedure is commonly known as SILS and it leaves no scars.
Malabsorptive surgery includes gastric bypass and the biliopancreatic diversion [BPD]. In a gastric bypass, a small pouch of stomach is created using staplers and a loop of intestine is attached to it. The stomach and first part of intestines are bypassed. This leads to restriction of food intake coupled with malabsorption of nutrients.
A gastric bypass is considered as a gold standard and leads to about 85 per cent excess weight loss. It leads to resolution of diabetes within 7 – 10 days.
Biliopancreatic diversion is not recommended for Indians, as the post-surgery nutritional requirements are difficult to meet with Indian diet.
All the surgeries are done laparoscopically and the patient is usually home within 48 hours.