Obesity

 

Obesity is the presence of excess fat in the body. It is linked to many diseases such as diabetes, hypertension, cardiovascular disease, cancer, osteoarthritis, and chronic kidney disease.

Obesity is measured by:

1. Body mass index (BMI) is the ratio of one’s body weight (in Kg) to the square of height (in meter). A BMI of more than 25 is considered overweight while a BMI of more than 30 is considered obese.

2. Waist circumference measures the accumulation of fat around the abdominal area (central adiposity). It measures waist to hip ratio. A waist circumference of more than 94 cm in men and 80 cm in women is considered unsafe.

 

 

Obesity occurs when the fat cells in the body increase in size and number. It can be caused due to:

1. Excess calorie intake: Intake of calories exceeds the number of calories spent. Just additional 220 calories (equivalent to taking a candy) consumed every day over a period of 1 year can cause a weight gain of 5 kg.

2. Sedentary lifestyle: Lack of physical activity

3. Unhealthy food choices: Consuming too much snack foods or greater serving sizes

4. Hormonal disorders: Such as thyroid disorders or polycystic ovary syndrome (PCOS)

5. Other factors that increase the risk of obesity include:

a) Family history: Risk of obesity is higher if one or both the parents are obese.

b) Childhood Obesity: Being obese during childhood increases the risk of being obese as an adult.

c) Genes: Some gene mutations or genetic disorders may cause obesity. For example, leptin gene mutation or leptin receptor mutation. Prader-Willi syndrome is a genetic disorder characterized by excessive hunger that leads to obesity

d) Drugs such as sleeping pills and antipsychotic drugs

e) Abnormal sleep pattern

 

 

Diagnosis of obesity is done on the basis of one’s BMI. The doctor will physically examine the patient and measure:

1. Height and weight to calculate the BMI

2. Waist circumference

3. Blood pressure

Medical history will be taken along with eating habits and the amount of physical activity. The doctor may perform blood tests for:

1. Fasting glucose

2. Lipid profile total cholesterol, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, and triglycerides

3. C-reactive protein

4. Thyroid hormones

 

 

The basic modality of management of obesity lies in lifestyle modifications. It includes the following:

1. Dietary changes: Restrict calorie intake to create a calorie deficit in the body so that energy expenditure exceeds the number of calories consumed. Consuming special diets may also reduce the intake of calories:

a) Low-fat diet (example, Ornish diet)

b) Low carbohydrate diet (for example, Atkins diet)

c) Low glycemic index diet
NOTE: DO NOT opt for crash dieting. Sudden weight loss may cause serious health problems as it slows down the metabolism and deprives the body of essential nutrients. It can also lead to weight gain in future.

2. Increase in physical activity and exercise on a regular basis are important in the prevention and management of obesity. Exercise can help increase energy expenditure and achieve the balance with calories consumed and spent. Do at least 150 minutes of exercise a week. 

Cardio exercises such as jogging, walking, running, swimming, aerobics help in burning calories. Try brisk walking at least 30 minutes a day. Weight training will help in long term weight loss along with retention of muscles. You can opt for chest press, shoulder press, leg press, leg extensions and leg curls.

3. Weight management programs that include lifestyle changes in the diet and physical activity may also help in losing weight.

4. Use of drugs:

a) Orlistat is an over-the-counter drug that prevents the absorption of fat in the body.

b) Lorcaserin suppresses the appetite by making a person feel full.

c) Topiramate and Phentermine suppress the appetite and when used along with dietary changes and exercise can help control weight.

5. Surgery is done for obesity only when the person is not able to lose weight by dietary changes, exercise, or medicines.

a) Liposuction involves reducing the excess fat from the body.

b) Bariatric surgery reduces the size of the stomach so that you eat less. It can be done in multiple ways.

c) Laparoscopic adjustable gastric banding places a silicone ring on the upper part of the stomach. It is attached to a tube that can be inflated. The tube connects to a port under the skin that can be used to inject or withdraw saline to adjust the band diameter. This helps in creating a small pouch with a narrow opening.

d) Roux-en-Y gastric bypass (RYGB) reduces the size of the stomach and then bypasses part of the small intestine to reduce absorption.

e) Sleeve gastrectomy reduces the size of the stomach by up to 75%. It involves separating a part of the stomach and removing it.

f) Biliopancreatic diversion removes a large part of the stomach and attaches it to ileum (a part of the intestine).

g) Biliopancreatic diversion with duodenal switch involves removing a large part of the stomach and then connecting the remaining part to the duodenum (the first part of the intestine). The duodenum is then directly connected to the last part of the small intestine thereby closing the middle part.

 

Obesity can cause serious health problems. It increases the risk of many other diseases such as:

1. Hypertension

2. Diabetes

3. Heart diseases

4. Kidney, gallbladder, or liver disease

5. Obstructive sleep apnea

6. Arthritis

7. Cancer -- Obesity in men increases the risk of colon, rectum, or prostate cancer. Obesity in women increases the risk of cancers of the reproductive system and gallbladder.

8. Obesity may also cause a negative self-image with reduced physical and social functioning.

9. See a doctor if you are gaining unintentional weight.

 

 

The prognosis depends on the cause of your obesity. Weight loss significantly reduces the risks associated with obesity.

Weight gain can be prevented by adopting a healthy lifestyle. These tips may help:

1. Keep a track of calories consumed.

2. Exercise regularly

3. Eat a healthy balanced diet rich in fiber and whole grains.

4. Avoid foods with high sugar and fat content such as cold drinks, packaged juices, cereals, bread, cookies, and cake frostings.

5. Take care of the portion size you are eating.

6. Eat three meals a day. When hungry between meals, snack on healthy food such as nuts and fresh fruits.

 

 

Klein S, Romijn JA. Obesity. In: Melmed S, Polonsky KS, Larsen PR, Kronenberg HM, eds. Williams Textbook of Endocrinology. 13th ed. Philadelphia, PA: Elsevier; 2016:chap:36.

Bray GA. Obesity. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger and Fordtran's Gastrointestinal and Liver Disease. 10th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 7.