Definition of Obesity
The ideal weight in the medicine is based on the principle of improving health, generally Body Mass Index (BMI) is used.
1. Body Mass Index (BMI)
The calculation of BMI is using the body weight (unit: kg) divided by the square meter of the height (unit: meters)(BMI = kg/ m2). Normally speaking, the adult BMI shall be between 18.5 and 24, over 24 is overweight, and over 27 is obese, the BMI of over 35 combining with the hypertension, diabetes, etc, and BMI over 40 is considered as morbid obesity. According to the Body Mass Index (BMI), the ideal index is 22 for the life and health, it is the same for both men and women. So the ideal weight calculation is: height (in meters) X height (in meters) X 22.
2. Waistline
The waistline is also a standard to evaluate the obesity, if the men’s waistline is over 90 cm and the women’s waistline is over 80 cm are considered as obese.
According to the different Body Mass Index (BMI), we can also see whether our body weight is ideal or not, the following table is a comparison of the Body Mass Index (BMI):

	Body Mass Index (BMI) （kg/ m2）	waistline (cm)
Overweight	BMI＜18.5
Normal	18.5≦BMI＜24
Abnormal	Overweight：24≦BMI＜27 Light obese：27≦BMI＜30 Moderate obese：30≦BMI＜35 Severe obese：BMI≧35 Morbid Obese：BMI≧40 Super obese：BMI≧50	Men：≧90cm Women：≧80cm

Cardiovascular diseases
1.Hypertension: It is related to the increase in the cardiac output and blood vessel pressure.
2.Coronary artery diseases: The hypertension, high cholesterol and diabetes caused by obesity are the main factors of causing coronary artery disease.
3.Cerebrovascular diseases and diseases of vascular embolism: hypertension, high cholesterol and diabetes can all cause atherosclerosis and increase the risk of stroke. The obese patients are also easily suffered from vein embolism of the lower extremities and cause embolism of pulmonary and cerebral blood vessels.

Respiratory diseases
Hypoventilation syndrome, Obstructive Sleep Apnea Syndrome

Diseases of the digestive system
Gallstone, fatty liver: The obese patients do not only have high risk of gallstone, but also acute cholecystitis. The nonalcoholic fatty liver disease (NAFLD) can cause hepatomegaly, abnormality of the liver function, hepatitis and even cirrhosis. The obese patients are also complicated with Gastro-esophageal regurgitation disease and cause damage and deformation to esophagus.

Joints diseases
Degenerative arthritis:
The overweight can make the joints to support more weight, and it can cause degeneration of the joints producing arthritis, especially the knee joints. The obese patients are often suffered from low back pain.

Reproductive diseases
The risk of infertility of the obese women is 30% higher than the normal weight women, because the excess of fat can influence the secretion of hormones and change the ovulation function of the ovaries, causing the menstruation disorders and infertility. They also suffer Polycystic Ovarian Syndrome more easily. Obesity can also influence the sexual function, the excess of the fat can influence the secretion of sexual hormone, causing the reduction of sexual desires and functional disorders, so the obese men have higher chance of impotence.

Dermatologic diseases
The obese patients often suffer friction dermatitis at skin folding area including neck, axilla, genitals and buttocks, causing red and itching eczema. The obstruction of the venous return of the lower extremities can also cause varicose veins and dermatitis.
Psychological diseases
The obese patients easily have Feeling of inferiority and lack of self-esteem, and even depression.
Cancer
The obese patients have higher risk of suffering colon and rectal cancer, prostate cancer, endometrial carcinoma, gallbladder cancer, ovarian cancer and breast cancer.
BMI & Mortality ratio
We also discover that the Body Mass Index (BMI) can influence the mortality rate. People with higher or lower BMI have more risk of suffering diseases than those whose BMI is between 22-25,and the mortality rate is also higher. Therefore, it is very important to maintain an ideal weight.

Obesity and diseases
The obesity can cause the following diseases:
Endocrine diseases
1.Diabetes: The obese patients have lots of fat tissues, this can cause an increased secretion of insulin, the result of high amount of secretion would increase the resistance of insulin and then pancreatic insufficiency, this will further induce hyperglycemia .
2.Hyperlipidemia, hyperuricemia and gout are all related to obesity.

Laparoscopic bariatric surgery at E-Da Hospital
Bariatric surgery has made obvious progress due to the improvement of the laparoscopic equipment and techniques. Because the operation with laparoscope can reduce the pain and accelerate the recovery time of the patients, avoiding the complication of the wound and heart and lungs, and there is further advantage of nice-looking, therefore, it has become the main stream of the obesity treatment.

After the creation of the Minimally Invasive Surgery Center of the E-Da Hospital, we have introduced many newest laparoscopic equipment and techniques to benefit more obese patients. There are many obese patients have received the laparoscopic bariatric surgery in our hospital. Normally speaking, there are only 5 needle sized wounds after laparoscopic bariatric surgery, and they can get off the beds on the same day of the operation, and discharged on the next day. One year after the operation the patients can lose 80% of the excess body weight.

Indication of operation:
1.Morbid obesity: The weight has surpassed 100 pounds (about 45 kg) of the ideal weight, or BMI≧35 with combination of diseases caused by the obesity, or the BMI is over 40.
2.Obesity more than 5 years
3.No effectiveness of diet or drug control
4.No alcoholic addiction or psychological problems
5.Obesity not caused by the drugs, metabolic or endocrine diseases
6.Between 14-60 years of age

Vitamins Supplement after bariatric surgery
Vitamins mal-absorption: Patients who have received the Roux-en-Y Gastric bypass could encounter long-term vitamin deficiency problems due to bypassing the small intestines. Normally, the absorption of B12, calcium and iron has been dramatically influenced. Please take the vitamins according to the doctor’s instructions, and the dietician would also teach you how to supple the vitamins from your foods. The gastric banding and sleeve gastrectomy have less these problems.

Possible complications of bariatric surgery
The US National Institutes of Health (NIH) has made the conclusion in 1991: the risk of bariatric surgery is much lower than the diseases caused by the morbid obesity. It is also the fact. Comparing to the death rate of the diseases caused by diabetes, hypertension, high cholesterol, etc., in fact the operation risk is very low. And from the clinical data; the following cases have a higher risk of complication: advanced age, super-obese, or who had ever received bariatric surgery before. Of course, the condition of each patient is different, it is important to have a good communication with the doctors before operation. The doctors will propose and arrange a suitable operation for you according to the results of your physical examination. The followings are the possible complications of the operation

1) Death: According to data, the mortality rate of bariatric surgery is around 1/200.Generally speaking, the definition of mortality is within 30 days after operation. Till now, there is no mortality in our hospital.

2) Gastric pouch leakage: It is caused by the poor healing of the gastric pouch or improper diet after the operation, which is very rare. In case it occurs, it is possible that a second laparoscopic operation is necessary.

3) Pulmonary embolism: The obese patients who have higher risk of embolism due to the poor blood circulation of the leg veins. And if the embolism comes to the cardiopulmonary circulation, it could cause a fatal pulmonary embolism. The patients with blood coagulation disorders or super-obese have higher risk, therefore, during the operation, our surgical team will arrange compressing device of the legs in order to reduce the risk.

4) Heart attack: the obese patients can have arteriosclerosis due to the high cholesterol, which can cause heart attack after operation. We would arrange a series of cardiovascular examinations before the operation. If there is any problem of vascular problems, normally it is proposed to treat the heart disease first.

5) Gastrointestinal tract hemorrhage: Because the operation involves incision and anastomosis of the gastrointestinal tracts, sometimes there could be bleeding situation from the gastrointestinal tracts after the operation. You will find melena or bloody stool passage and that needs hospitalization treatment. Normally, medical treatment can solve these problems.

6) Pneumonia: The patients who have received traditional laparotomy are less active because of pain and can have much sputum hard to clean, inducing atelectasis of lung or pneumonia. But in laparoscopic operation patients can get off bed soon, so this complication is rare.

7) Intestinal obstruction: All patients who received abdominal surgery could have this problem, normally it caused by adhesion or internal hernia, but in laparoscope this problem is very rare.

8) Anastomotic leakage: Because the operation involves the incision and anastomosis of the gastrointestinal tracts, rarely leakage can occur at the anastomosis of gastrointestinal tracts after the operation. At this time, abdominal pain, fever or palpitation can occur. Generally speaking, the necessity of re-operation is <1 %.

9) Anastomotic stricture: Normally it occurs at the anastomosis of the gastric pouch and small intestines. And patients would vomit even after taking liquid food. Mostly the symptoms can be relieved with gastroscopic dilatation, normally speaking, the possibility is < 5%.

10) Infection of the gastric band: The gastric band is made of silicone, a foreign body, and sometimes there is an infection of the gastric band. It will be necessary to remove it if infected and a second operation will be arranged in the future.