Obesity: Risks & Causes ?

The definition of obesity varies depending on what one reads, but in general, it is a chronic condition defined by an excess amount body fat. A certain amount of body fat is necessary for storing energy, heat insulation, shock absorption, and other functions. The normal amount of body fat (expressed as percentage of body fat) is between 25%-30% in women and 18%-23% in men. Women with over 30% body fat and men with over 25% body fat are considered obese.

The calculation of body mass index (BMI) has also been used in the definition of obesity. The body mass index (BMI) equals a person's weight in kilograms (kg) divided by their height in meters (m) squared. Since BMI describes body weight relative to height, it is strongly correlated with total body fat content in adults. "Obesity" is defined as a BMI of 30 and above.

Health risks associated with obesity?

Obesity is not just a cosmetic consideration; it is a dire health dilemma directly harmful to one's health. In the United States, roughly 300,000 deaths per year are directly related to obesity, and more than 80% of these deaths are in patients with a BMI (body mass index, which will be discussed later in this article) over 30. For patients with a BMI over 40, life expectancy is reduces significantly (as much as 20 years for men and 5 years for women ).

Obesity also increases the risk of developing a number of chronic diseases including:

• Insulin Resistance: Insulin is necessary for the transport of blood glucose (sugar) into the cells of muscle and fat (which is then used for energy). By transporting glucose into cells, insulin keeps the blood glucose levels in the normal range. Insulin resistance (IR) is the condition whereby the effectiveness of insulin in transporting glucose (sugar) into cells is diminished. Fat cells are more insulin resistant than muscle cells; therefore, one important cause of insulin resistance is obesity. The pancreas initially responds to insulin resistance by producing more insulin. As long as the pancreas can produce enough insulin to overcome this resistance, blood glucose levels remain normal. This insulin resistance state (characterized by normal blood glucose levels and high insulin levels) can last for years. Once the pancreas can no longer keep up with producing high levels of insulin, blood glucose levels begin to rise, resulting in type 2 diabetes, thus insulin resistance is a pre-diabetes condition. In fact scientists now believe that the atherosclerosis (hardening of the arteries) associated with diabetes likely develops during this insulin resistance period.

• Type 2 Diabetes. The risk of type 2 diabetes increases with the degree and duration of obesity. Type 2 diabetes is associated with central obesity; a person with central obesity has excess fat around his/her waist, so that the body is shaped like an apple.

• High blood pressure (hypertension). Hypertension is common among obese adults. A Norwegian study showed that weight gain tended to increase blood pressure in women more significantly than in men. The risk of developing high blood pressure is also higher in obese people who are apple shaped (central obesity) than in people who are pear shaped (fat distribution mainly in hips and thighs).

• High cholesterol (hypercholesterolemia)
• Stroke (cerebrovascular accident or CVA)
• Heart attack. A prospective study found that the risk of developing coronary artery disease increased three to four times in women who had a BMI greater than 29. A Finnish study showed that for every one kilogram (2.2 pounds) increase in body weight, the risk of death from coronary artery disease increased by one percent. In patients who have already had a heart attack, obesity is associated with an increased likelihood of a second heart attack.
• Congestive heart failure
• Cancer. While not conclusively proven, some observational studies have linked obesity to cancer of the colon in men and women, cancer of the rectum and prostate in men, and cancer of the gallbladder and uterus in women. Obesity may also be associated with breast cancer, particularly in postmenopausal women. Fat tissue is important in the production of estrogen, and prolonged exposure to high levels of estrogen increases the risk of breast cancer.
• Gallstones
• Gout and gouty arthritis
• Osteoarthritis (degenerative arthritis) of the knees, hips, and the lower back
• Sleep apnea

What Causes Obesity?

The balance between calorie intake and energy expenditure determines a person's weight. If a person eats more calories than he or she burns (metabolizes), the person gains weight (the body will store the excess energy as fat). If a person eats fewer calories than he or she metabolizes, he or she will lose weight. Therefore the most common causes of obesity are overeating and physical inactivity.

At present, we know that there are many factors that contribute to obesity, some of which have a genetic component:

• Genetics. A person is more likely to develop obesity if one or both parents are obese. Genetics also affect hormones involved in fat regulation. For example, one genetic cause of obesity is leptin deficiency. Leptin is a hormone produced in fat cells, and also in the placenta. Leptin controls weight by signaling the brain to eat less when body fat stores are too high. If, for some reason the body cannot produce enough leptin, or leptin cannot signal the brain to eat less, this control is lost, and obesity occurs. The role of leptin replacement as a treatment for obesity is currently being explored.

• Overeating. Overeating leads to weight gain, especially if the diet is high in fat. Foods high in fat or sugar (for example, fast food, fried food, and sweets) have high energy density (foods that have a lot of calories in a small amount of food). Epidemiologic studies have shown that diets high in fat contribute to weight gain.

• A diet high in simple carbohydrates. The role of carbohydrates in weight gain is not clear. Carbohydrates increase blood glucose levels, which in turn stimulate insulin release by the pancreas, and insulin promotes the growth of fat tissue and can cause weight gain. Some scientists believe that simple carbohydrates (sugars, fructose, desserts, soft drinks, beer, wine, etc.) contribute to weight gain because they are more rapidly absorbed into the blood-stream than complex carbohydrates (pasta, brown rice, grains, vegetables, raw fruits, etc.) and thus cause a more pronounced insulin release after meals than complex carbohydrates. This higher insulin release, some scientists believe, contributes to weight gain.

• Frequency of eating. The relationship between frequency of eating (how often you eat) and weight is somewhat controversial. There are many reports of overweight people eating less often than people with normal weight. Scientists have observed that people who eat small meals four or five times daily, have lower cholesterol levels and lower and/or more stable blood sugar levels than people who eat less frequently (two or three large meals daily). One possible explanation is that small frequent meals produce stable insulin levels, whereas large meals cause large spikes of insulin after meals.

• Slow metabolism. Women have less muscle than men. Muscle burns (metabolizes) more calories than other tissue (which includes fat). As a result, women have a slower metabolism than men, and hence, have a tendency to put on more weight than men, and weight loss is more difficult for women. As we age, we tend to lose muscle and our metabolism slows; therefore, we tend to gain weight as we get older particularly if we do not reduce our daily caloric intake.

• Physical inactivity. Sedentary people burn fewer calories than people who are active. The National Health and Nutrition Examination Survey (NHANES) showed that physical inactivity was strongly correlated with weight gain in both sexes.

• Medications. Medications associated with weight gain include certain antidepressants (medications used in treating depression), anti-convulsants [medications used in controlling seizures such as carbamazepine (Tegretol, Tegretol XR , Equetro, Carbatrol) and valproate], diabetes medications (medications used in lowering blood sugar such as insulin, sulfonylureas and thiazolidinediones), certain hormones such as oral contraceptives and most corticosteroids such as Prednisone. Weight gain may also be seen with some high blood pressure medications and antihistamines.

• Psychological factors. For some people, emotions influence eating habits. Many people eat excessively in response to emotions such as boredom, sadness, stress or anger. While most overweight people have no more psychological disturbances than normal weight people, about 30 percent of the people who seek treatment for serious weight problems have difficulties with binge eating.

• Diseases such as hypothyroidism, insulin resistance, polycystic ovary syndrome and Cushing's syndrome, are also contributors to obesity.

More info :

22% children suffering from obesity: Study

Srinagar, May 4: In what could set alarm bells ringing, around 22 per cent urban and semi- urban Kashmiri children have been found suffering from obesity- the main cause of disease like diabetes and cardiac ailments.

This was revealed in a study conducted by the department of Endocrinology, SK Institute of Medical Sciences on 5000 children. Talking to local newspaper SKIMS, Director, Dr Abdul Hamid Zargar said, “ We completed the study three months ago and found 22 per cent children suffering from obesity,” Dr Zargar said.

He said the finding was worrisome as it shows that obesity, which was prevalent in people above 40- years, was now occurring at 20 years. He said it would affect the quality of life in coming years adding the children would be more susceptible to lifestyle diseases like diabetes, cardiac ailments and hypertension.

“ It means the children, if left untreated, will spent major portion of their life as diseased,” he said.

Dr Zargar held changed lifestyle responsible for growing obesity among children.

“ Earlier, kids used to walk miles and availability of food was according to the need. But now there is more food than required, intake of chocolates and junk food has increased,” he said.

“ During my student days in medicine, we would rarely receive any youth suffering from diabetes or cardiac ailments. But now there is hardly any week when we don’t receive such patients barely of 30 to 35 years. We frequently receive obese girls of 15 year suffering from diabetes,” he said.

He said the kidney ailments due to diabetes were also increasing. “ We receive 50 cases of kidney failures at SKIMS each month.” A separate SKIMS Study had shown that the Kashmir youth was highly susceptible to diabetes. The study in which 11000 people were randomly shown showed that 27 per cent youth in the age group between 25 and 40 were living in pre- diabetes condition while as eight percent above 40 years had diabetes.

Meanwhile, during a symposium on lifestyle disease organized by Gilan Foundation at the Revenue Training Institute here on Monday, the experts said the diabetes and cardiac ailments were prevalent among the youth.

Speaking on the occasion, Dr Zargar said “ The increased patient rush has exhausted the SKIMS resources. We are in the process of getting SKIMS- II, but I doubt if that could be of any help due to huge increase in the patient rush.” Justice ( Retd) Bashir Ahmad Kirmani opined that people should gain spirituality and sincerity to avoid stress. “ We shall not call it lifestyle but it is lack of style which we are witnessing in the society. We need to avoid stress which affects life and causes diseases.” local news paper Columnist, Z G Muhammad stressed on the need for attitude change for prevention and treatment of lifestyle disease.

“ Besides changed lifestyle being a cause of diabetes, attitude is big contributor to such ailments.
We need to change our attitude towards life,” he said, adding, “ Lifestyle diseases have to do with psychological status of an individual. I have personal experience keeping oneself busy can help in living a better life.”

Danish Nabi