Facts
The World Health Organisation (WHO) defines overweight and obesity as abnormal or excessive fat accumulation that presents a risk to health.
Worldwide more than 1 billion adults are currently overweight with approximately 1/3 of these being clinically obese (BMI >30). This obesity epidemic is now a major contributor to the global healthcare burden. In individual countries obesity rates vary from 5% (China and Japan) to 66% in the US and 75% in urban Samoa.More worrying is the 22 million children under five currently estimated to be overweight worldwide. According to the US Surgeon General, in the USA the number of overweight children has doubled and the number of overweight adolescents has trebled since 1980. In 2004 the American Medical Association placed obesity as the second highest cause of death in the USA.
USA Death Statistics 2004 (American Medical Association) | |
Smoking Obesity Infection Alcohol Toxic Motor Guns Sexual | 435,000 385,000 75,000 65,000 55,000 43,000 29,000 20,000 |
No mater how alarming the health economic data is, it is extremely important to not forget the significant cost of obesity to the individual. These include:-
l Lost output due to reduced ability to work or cessation of productivity
l Reduced quality of life
l Increased morbidity (cardiac disease, diabetes and arthritis)
l Premature mortality (heart disease, cancer, diabetes, liver disease)
l Stigmatization within society
l Decreased opportunity in education, housing and employment
How do we define obesity and overweight?
Obesity is assessed using body mass index (BMI) which is defined as the weight in kilograms divided by the square of the height in metres (kg/m2). Whilst BMI provides a benchmark for comparative assessment, risks of disease in all populations increase progressively from lower BMI levels.In Africa and Asia, adult mean BMI levels are 22-23 kg/m2 whilst levels of 25-27 kg/m2 are prevalent across North America, Europe, and in some Latin American, North African and Pacific Island countries. BMI also increases amongst middle-aged elderly people, who are at the greatest risk of health complications. The distribution of BMI is shifting upwards in many populations.
WHO Body Mass Index (BMI) Classification | |
Less than 18.5 18.5 to 24.9 25.0 to 29.9. 30.0 to 34.9 35.0 to 39.9 40.0 to 49.9 >50 | Underweight Normal or Healthy Range Overweight Obese Severely Obese Morbid Obese Super Obese |
Why is this happening?
The rising epidemic reflects changes in society and its behavioural patterns over recent decades. Undoubtedly, genetic inheritance is important in determining a person's susceptibility to weight gain however energy balance is determined by calorie intake and physical activity. Thus as incomes rise and populations become more urban, diets high in complex carbohydrates have given way to more varied diets with a higher proportion of fats, saturated fats and sugars. At the same time, shifts towards less physically demanding work, and moves towards less physical activity through the increasing use of automated transport, technology in the home, and more passive leisure pursuits have been seen worldwide. Put simply,“Energy balance is determined by calorie intake and physical activity”
Ironically, contrary to common belief, the obesity epidemic is not just restricted to industrialized societies and the epidemic is seen to be growing faster in some developing countries which are currently experiencing the rapid introduction of modern energy saving technology and western high calorie foodstuffs. How does excess body fat impact health?
The health consequences of obesity range from increased risk of premature death, to serious chronic conditions that reduce the overall quality of life. Obesity is a major risk for life threatening related chronic diseases including type 2 diabetes, cardiovascular disease, hypertension, stroke, certain forms of cancer (breast, colon, prostate, endometrium, kidney and gallbladder) and gallbladder disease.Being overweight can lead to adverse metabolic effects on blood pressure, cholesterol, triglycerides and insulin resistance. Other non-fatal, but debilitating health problems associated with obesity include respiratory problems (sleep apnoea), chronic musculoskeletal problems (including osteoarthritis – a major cause of disability), skin problems, infections and infertility.
Obesity should probably be considered a disease in its own right as together with smoking, high blood pressure and high blood cholesterol it is a recognised key risk factor for many other chronic diseases. In the analyses carried out for World Health Report 2002, approximately 58% of diabetes and 21% of ischaemic heart disease and 8-42% of certain cancers globally were attributable to a BMI above 21 kg/m2.
Economists with RTI International, a non-profit research organization in Research Triangle Park, N.C., analyzed national data on 366,000 people. Among the findings published online in the journal Obesity, they found that:
•Overall, excess weight was responsible for the loss of roughly 95 million years of life in the USA in 2008.
•Non-smokers who are obese (about 30 or more pounds over a healthy weight) have a shorter life span by a year or less.
•Smoking takes a toll, too, and very heavy smokers are affected most. An 18-year-old white male who is normal weight and does not smoke can expect to live to age 81. If he's extremely obese and a smoker, his life expectancy is 60, a difference of 21 years.
What can society do about it?
“Inside every obese person there is a small person trying to get out”
Effective weight management for individuals and groups at risk of developing obesity involves a range of long-term strategies. These include prevention, weight maintenance, management of co-morbidities and weight loss. Key elements include:- Creating supportive environments through public policies that promote low-fat, high-fibre foods, and that provide opportunities for physical activity.
- Promotion of healthy behaviour to encourage, motivate and enable individuals to lose weight by
- eating more fruit and vegetables, nuts and whole grains;
- engaging in daily moderate physical activity for at least 30 minutes;
- cutting the amount of fatty, sugary foods in the diet;
- moving from saturated animal-based fats to unsaturated vegetable-oil based fats.
- Promoting medical treatments for the existing burden of obesity and associated conditions with effective support for those affected to lose weight or avoid further weight gain.
Medical and Surgical Options
Whilst lifestyle changes, low calorie diets, increased exercise and some medical treatments remain the ideal way to loose weight, some patients are unable to achieve the weight loss necessary to return to a health BMI.
Many surgical techniques have been developed and today interest in obesity (Bariatric) surgery is a growing at a faster than ever before. Broadly speaking three surgical options exist.
The water filled Intragastric (BIB®) Balloon is placed in the stomach using an endoscope passed through the mouth under sedation. The procedure takes about 15 minutes and does not require surgery. It is effective in patients who are overweight (BMI 25.0–29.9). It is sometimes used in special circumstances for patients with very high BMIs to rapidly reduce the liver fat content prior to surgery. The balloon is removed once the target weight is reached.
For patients with BMI’s greater than 30, the balloon is not so effective and two surgical treatments are available.
Gastric by-pass surgery including the gastric by-pass and duodenal switch are major irreversible operations which reduces the size of the stomach and short circuit the small intestine to create a permanent state of malabsorption. The operation is very effective but involves cutting and joining the intestine in a number of places. It is associated with a significant surgical complication rate and post operative biochemical problem including vitamin, iron and calcium malabsorption which can occur in up to 30% of patients. This requires lifelong supplements to be taken.
The adjustable laparoscopic gastric band (Lap Band®), is a device which is placed around the neck of the stomach using keyhole surgery and which can be intermittently adjusted to restrict the amount of food that can be eaten. The Lap Band is as effective as the gastric by-pass techniques at helping a patient loose weight, however the technique has the distinct advantage of not altering the intestinal tract and not dividing the bowel. The surgical complications are much lower with this procedure and there are no associated vitamin, iron or calcium nutritional problems. The device can be removed once the patient reaches their target weight.
When considering what way to best loose weight, the preferred option is by reversing the “energy in / energy out” imbalance by diet and exercise. If you opt for one of the surgical options, to ensure the best long term results, your team should be able to offer you dietetic, surgical, endocrine medical and fitness training support an be committed to working with you towards your goal.
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