Obesity

This excerpt is taken from Wikipedia

United Kingdom

The Health Survey for England predicts that more than 12 million adults and 1 million children will be obese by 2010 if no action is taken.^[18][19] The prime minister has urged people to take more responsibility for their fitness and diet.^[20]

United States

The prevalence of overweight and obesity in the United States makes obesity a leading public health problem. The United States has the highest rates of obesity in the developed world. From 1980 to 2002, obesity has doubled in adults and overweight prevalence has tripled in children and adolescents.^[21] From 2003-2004, "children and adolescents aged 2 to 19 years, 17.1% were overweight...and 32.2% of adults aged 20 years or older were obese."^[21] The prevalence in the United States continues to rise.^[21] The prevalence of obesity has been continually rising for two decades.^[22] This sudden rise in obesity prevalence is attributed to environmental and population factors rather than individual behavior and biology because of the rapid and continual rise in the number of overweight and obese individuals.^[23] The current environment produces risk factors for decreased physical activity and for increased calorie consumption. These environmental factors operate on the population to decrease physical activity and increase calorie consumption.

Q: What are the health consequences of obesity?

A: Obesity is a potentially deadly condition. Poor nutrition and physical inactivity account for some 300,000 premature deaths in the United States each year. ³ Obesity-related illness results in hundreds of thousands of preventable deaths each year in the United States and billions of dollars in health care costs.

Being obese causes an increased risk for developing a number of serious and potentially lethal health problems, including: hypertension/high blood pressure, non-insulin-dependent or Type 2 diabetes, heart disease and stroke, and gallstones and gall bladder disease. The Centers for Disease Control also include the following in their list of possible health consequences of obesity:

• High blood cholesterol, dyslipidemia
• Insulin resistance, glucose intolerance
• Congestive heart failure
• Cholescystitis and cholelithiasis
• Gout
• Osteoarthritis
• Some types of cancer (such as endometrial, breast, prostate, and colon)
• Complications of pregnancy
• Poor female reproductive health (such as menstrual irregularities, infertility, irregular ovulation)
• Bladder control problems (such as stress incontinence)
• Psychological disorders (such as depression, eating disorders, distorted body image, and low self- esteem)

There are also other gender-specific health risks among obese women and men. For example, according to the National Women's Health Resource Center, if a woman’s waist circumference is more than 35 inches, she is considered to have a high amount of visceral fat, which is the type of fat that surrounds the internal organs. This type of fat is associated with higher risk of certain, serious diseases (e.g. liver disease) and chronic conditions like diabetes and heart disease.

Several of the most severe and prevalent life-threatening illnesses among the male population are also correlated to obesity. Obese men are more likely than non-obese men to die from cancer of the colon, rectum, or prostate. ⁴ Obese men are also more likely than women to suffer from sleep apnea, a very serious, possibly life-threatening condition which is associated with stroke and heart attack.

Increased Health Risk of Premature Death

According to CDC researchers, an estimated 300,000** American deaths a year are related to obesity, but see note, below. The risk of premature death rises with increasing weight. Even moderate weight gain (10 to 20 pounds for a person of average height) increases the risk of death, particularly among adults aged 30 to 64 years. Individuals who are obese (BMI greater than 30) have a 50 to 100 percent increased risk of premature death from all causes, compared to individuals with a healthy weight.

Increased Health Risk of Heart Disease

The risk of heart attack, congestive heart failure, sudden cardiac death, angina or chest pain is increased in persons who are overweight or obese. High blood pressure is twice as common in adults who are obese than in those who are at a healthy weight. Obesity is associated with high triglycerides and decreased HDL cholesterol.

Increased Health Risk of Stroke

Atherosclerosis, or narrowing of the arteries, which may lead to the formation of an arterial blood clot, is an important pre-condition of many strokes. Atherosclerosis is accelerated by high blood pressure, smoking, high cholesterol and lack of exercise. Obesity, especially morbid obesity is frequently associated with a high-fat diet, raised blood pressure and lack of exercise. Thus obesity is now considered an important secondary risk factor for strokes.

Increased Health Risk of Type 2 Diabetes

A weight increase of 11-18 pounds raises a person's risk of developing type 2 diabetes to twice that of individuals who have not gained weight. Over 80 percent of people with diabetes are overweight or obese. This may account for the newly invented word, "diabesity"®, which signifies the close association between obesity and diabetes.

Increased Health Risk of Cancers

Obesity is associated with an increased risk for some types of cancer including endometrial (cancer of the lining of the uterus), colon, gall bladder, prostate, kidney, and post-menopausal breast cancer. Women gaining more than 20 pounds from age 18 to midlife double their risk of post-menopausal breast cancer, compared to women whose weight remains stable.

Increased Health Risk of Fatty Liver Disease

The main cause of non alcoholic fatty liver disease is insulin resistance, a metabolic disorder in which cells become insensitive to the effect of insulin. One of the most common risk factors for insulin resistance is obesity, especially central abdominal obesity. Studies indicate a correlation between body mass index (BMI) and the degree of liver damage. The higher the BMI the worse the liver disease.

Obesity is a Risk Factor For Chronic Venous Insufficiency

Although obesity is not a direct cause of chronic venous insufficiency, it is an important risk factor. This is because obesity, especially morbid obesity, leads to raised blood pressure, a sedentary lifestyle and musculoskeletal problems (hampering mobility and use of leg muscles), all of which are contributory factors in the development of chronic venous insufficiency. Obese patients also have an increased health risk of other vascular disorders (eg. lower-limb ischemia), caused by inadequate blood flow to the extremities.

Increased Health Risk of Gallbladder Disease

The risk of gallstones is approximately 3 times greater for obese patients than in non-obese people. Indeed, the risk of sympomatic gallstones appears to correlate with a rise in body mass index (BMI).

Increased Health Risk of Breathing Problems

Obstructive sleep apnea (that is, interrupted breathing during sleeping) is more common in obese persons. Obesity is associated with a higher prevalence of asthma and severe bronchitis, as well as obesity hypoventilation syndrome and respiratory insufficiency.

Obesity and Deep Vein Thrombosis

Risk factors for deep vein thrombosis include prior history of the disease, vascular damage, hypertension and predisposition to blood clotting. Although obesity (BMI 30+) has traditionally been recognised as a risk factor for deep vein thrombosis and pulmonary embolism, experts now consider that the evidence supporting this association is inadequate, as much depends on other factors such as history, illness, immobility, and age.

Increased Health Risk of Arthritis

musculoskeletal disorders, including osteoarthritis, are much more prevalent among obese patients, especially patients diagnosed with severe clinical or mobid obesity. Health studies show that obesity is a strong predictor for symptoms of osteoarthritis, especially in the knees. The risk of osteoarthritis increases with every 2-pound gain in weight.

Increased Health Risks For Expectant Mother and Baby

Obesity has a strong detrimental effect on the health of both mother and new-born baby, both during and after pregnancy. Obesity while pregnant is associated with a higher risk of death in both the baby and the mother. It also raises the risk of high blood pressure in the Mom, by 10 times. Obesity during pregnancy is also associated with an increased risk of birth defects, such as spina bifida. Obesity-related health problems occurring after childbirth include higher risk of wound and endometrial infection, endometritis and urinary tract infection.

So, you think that more exercise is the answer, then read this.

Most people are incredulous when told that clinical studies provide no evidence that exercise promotes weight loss either with or without dieting. The exercise industry has yet to inform the public of this rather important caveat. Of course, letting this simple truth out of the bag would be very bad for business. In the area of public health the 'truth' is highly negotiable. Much of what the public has come to believe is marketing, not science. Health edicts based on cherrypicking the evidence have become the unfortunate norm.

In theory, exercise should promote weight loss, so why doesn't the theory work in the real world? One reason is that fat is such a good source of energy. One kg of fat provides enough energy to keep us going for about four days even if we eat nothing. Expressed another way, one kg of fat is the energy equivalent of walking 80 miles. If you are a brisk walker, that could take as little as 16 hours.

Any increase in energy expenditure not compensated for by increased energy intake must cause weight loss. This is simple physics. However, mountains of data show that in the long run, exceedingly few can increase their energy expenditure enough to make a difference to their weight. Like it or not, the facts speak for themselves. To hector entire populations about what is at most a highly equivocal lifestyle deficiency has considerable potential for harm. Such an assault on the simple joys of leisure can only increase feelings of helplessness and self-loathing. Exercise may well have other benefits, but its impact on weight loss is negligible. It is not the moral or health imperative that its advocates make it out to be. The strident advocacy of 'run for your life' is yet another instance of pseudo-scientific tinkering with the lifestyles of entire nations.

30 January 2004

Dale M. Atrens, Ph.D. is Reader Emeritus in Psychobiology at the University of Sydney and Research Scholar at the River Centre Clinic, Sylvania, Ohio.