Obesity is defined as an increase in body fat composition. This increase results in an increase in weight and although not all body weight increase is due to increased adipose tissue, in medical practice the concept of obesity is related to body weight. Obesity should be understood as a chronic disease, similarly to what is diabetes mellitus or hypertension.
Obesity is a chronic, complex and multi-factorial disease, which usually begins in childhood and adolescence, and having its origin in a genetic and environmental interaction, the most important being the environmental or behavioral part, which is set by an imbalance between intake and energy expenditure.
Obesity is the most prevalent metabolic disease in the Western world and is a great source of morbidity, mortality and costs. The increased risk of mortality in relation to obesity is in part associated with the alterations that constitute the so-called metabolic syndrome. The economic effects of obesity are very important . Attributable to obesity economic cost includes direct costs (care for obesity – related diseases) and indirect (lost productivity).
Diagnosis of obesity
The degree of obesity is established in relation to body mass index (BMI) or Quetelet index, measured in kg / m 2 . It is obtained by dividing weight in kilograms by the square of the height in meters, as numerous studies have shown correlation with total body fat.
According to the Body Mass Index (BMI):
18.5-24.9 kg / m 2 Normal Weight
25 to 26.9 kg / m 2 Overweight grade I
27 to 29.9 kg / m 2 Overweight grade II
30-34.9 kg / m 2 Obesity Type I
35 to 39.9 kg / m 2 Obesity Type II
40 to 49.9 kg / m 2 Obesity Type III or morbid
50 Kg / m 2 Obesity Type IV or extreme
In obesity excess fat can be distributed throughout the body and can concentrate especially in certain body regions, so we speak of central obesity and peripheral obesity. When excess fat accumulates preferentially in the abdominal cavity, we speak of abdominal or central obesity. The most accurate way to quantify visceral fat is the measurement of intra – abdominal fat by abdominal CT or MRI at the level of fourth lumbar vertebra; A second way would be by abdominal ultrasound. In the usual practice, the definition of central obesity based on waist circumference or the ratio of waist circumference and hip circumference. Central obesity has more clinical significance than peripheral obesity as the intra – abdominal adipose tissue is metabolically more active than peripheral. The central obesity is an essential component of metabolic syndrome and a risk factor for development of diabetes mellitus type 2 and of cardiovascular disease.
What is the relationship between obesity and cancer?
Obese patients have a higher risk of certain cancers, particularly of hormone -dependent tumors. In obese women is more frequent endometrial, breast and gallbladder cancer. In men prostate cancer, and both sexes colon and rectum cancer.
Other health disorders associated with obesity
Obesity itself is a risk factor for the health of the population, which influences the development and progression of various diseases helping to reduce life expectancy in obese individuals, worsening their quality of life, limiting much of its activity and also causes problems of self – esteem, mobility, social relationship. Three factors directly influence this process: the degree of obesity, the time evolution of the same, and the age of obese individuals .
There is a direct relationship between BMI and the risk of morbidity and mortality of obese, which is derived from the associated diseases and obesity reaches convert a disease in itself and hence the term “morbid obesity”.
What diseases are associated?
Obesity is associated with many diseases, enhancing their appearance, facilitating their progression and worse prognosis, this fact is especially important in morbid obesity.
– Dyslipidemia : hypercholesterolemia, especially at increases of the LDL levels are common in patients with morbid obesity. The cause of occurrence of dyslipidemia in patients with morbid obesity is mixed and due to multiple factors. In untreated patients dyslipidemia favor endoluminal vascular deposits of atheroma and occurrence of ischemic heart disease.
– Arterial hypertension
– Venous stasis with hypercoagulation
– Type 2 Diabetes . 90% of diabetic patients are obese. The rate of complete resolution of type 2 diabetes after bariatric surgery is high and depends in part on the surgical technique used.
– Subclinical hypothyroidism
– Dysmenorrhea, impaired fertility and polycystic ovaries in women.
– Metabolic syndrome
– Hepatic steatosis, steatohepatitis and liver cirrhosis
– Cholelithiasis and acute cholecystitis
– Gastroesophageal reflux
Impaired quality of life
– Degenerative osteoarthritis
– Gout, hyperuricemia and maintained by uric acid deposits
– Urinary incontinence, abdominal hyperpressure and hypotonic pelvic floor
– Psychological disorders, especially depressive syndromes.