What is obesity?
A person’s height and gender determine what is a healthy weight. The terms ‘overweight’ and ‘obesity’ refer to body weight above what is considered healthy for a certain height. A useful measure to determine whether a person is overweight or obese is body mass index (BMI),which is calculated from height and weight.
The Australian population is ranked as one of the most overweight nations in the developed world. The number of Australians classed as obese (BMI > 30) has doubled during the past 20 years to more than five million people. Obesity is now the single biggest threat to public health in Australia and the leading cause of premature death and illness, with smoking second.
Being obese increases a person’s risk of diabetes, coronary artery disease, congestive heart failure, stroke, osteoarthritis, and some cancers. Reducing your weight by just 10% can delay or prevent the onset of some chronic diseases.
Until recently the connection between obesity and heart disease was believed to be indirect resulting from high blood pressure, dyslipidemia, cholesterol and insulin resistance or type 2 diabetes, with the likelihood increasing as BMI increased. However, doctors now know that obesity not only relates to, but also can independently predict the course of developing coronary artery disease.
Simply jumping on the scales to check your weight doesn’t really provide an accurate picture of body fat content. Bones, muscles, fluid, and fat all contribute to weight. To assess chronic disease risk, correlating height and waist measurements provides a more accurate pciture. The ratio of your weight to your height – your BMI – enables you to determine whether your health is at risk because you are overweight or obese. And measuring waist circumference indicates how much fat is deposited around the abdominal organs.
Maintaining a healthy weight is crucial to remaining well and preventing chronic disease. A healthy weight can help you keep cholesterol, blood pressure, and blood glucose levels under control and prevent disease dependent on weight, such as heart disease, diabetes, osteoarthritis, and some cancers.
Overeating or not getting enough exercise will cause a person to gain weight and become overweight or obese. To maintain an ideal weight, the calories you eat must equal the energy you burn each day. In order to lose weight, you must burn more calories than you eat.
Medicines, thyroid problems, heart failure, and kidney disease can cause sudden weight gain. Fluid retention, hormone imbalance, postpartum depression, alcohol abuse, and dysthYmia are additional reasons for gaining weight without overeating.
Unfortunately, obesity is a chronic disorder and less than 5% of people who manage to lose enough weight to reach their healthy weight range keep the weight off for four years or more. The habits adopted to lose the weight can be modified slightly, but must be maintained for a lifetime to prevent weight gain, which can happen so easily.
Prevention of obesity by diet and regular physical activity remains the highest priority for maintaining cardiovascular health. This is particularly important for small children and adolescents struggling with weight problems. Also, overweight children are more likely to become overweight or obese as adults, with the same disease risks.
Conventional medical treatment for obesity
Conventional medical treatment for obesity
The obesity epidemic continues to affect developed countries. Australia has one of the highest rates of overweight and obesity in the developed world, with more than 20% considered obese. In 2008 Australian healthcare costs reached $58.2 billion and obesity-related illness was the greatest contributing factor. The direct healthcare costs for obesity are though to exceed $8 billion per year.
Obesity has costly medical consequences – for productivity, the community, and the individual. Medication, restricted calorie diets, and surgery may all be considered for a very obese patient, particularly if health complications exist. The mainstay of treatment remains a low fat diet and increased physical activity, including medication for appetite where appropriate.
Many people struggle to lose excess weight. While choosing nutritious food and making time for regular physical activity can help, maintaining weight loss over the long term may require prescription medications.
Hormonal changes, hypothyroidism, hypercortisolaemia, and acromegaly are often blamed for obesity, but in reality they produce relatively minor weight increases.
A woman going through menopause is likely to deposit additional fat in the abdomen. Certain drugs can cause weight gain, such as steroids, some psychotropic and antidepressant drugs, and beta blockers may slow weight loss. Any medical condition that restricts mobility or activity, such as vision problems, musculoskeletal injury, severe arthritis, and depression can lead to weight gain.
To be successful, any treatment for obesity must revise diet, physical activity, cognitions, and behaviour in combination. While doctors continue to advise patients to eat less and exercise more, human frailty is such that less than 10% of people (Mel to check) successfully lose weight this way.
The prescription drugs currently available for the treatment of obesity generally are not ideal, so patients need to be selected carefully. Only those with significant hunger and overeating problems are usually prescribed obesity drugs, which have unpleasant side effects.
The drug orlistat (Xenical) is a pancreatic lipase inhibitor. It blocks the enzyme lipase, preventing approximately one-third of the food eaten from being digested. Without lipase fat cannot be broken down and absorbed, so the calorific content of food is artificially reduced. A person taking Orlistat should take a quality multivitamin because of the consequential reduction in nutrients being absorbed.
Orlistat works best when combined with a low fat diet. Orlistat reduces LDL cholesterol and has beneficial effects on some aspects of the syndrome X, including hypertension, type 2 diabetes, abnormal blood fat levels (low HDL,high LDL, high triglycerides), and waist circumference.
Lorcaserin acts on seratonin receptors in the brain that signal the stomach is full. A person feels fuller sooner and as a consequence eats less.
Phentermine-topiramate (Tompmax) combines phentermine to suppress appetite and topiramate to prevent any headaches caused by phentermine. It appears to have additional health benefits, including improved indicators for blood pressure, sugar levels, lipids, and inflammation.
Other appetite suppressants that curb hunger by affecting chemicals in the brain:
- phentermine (Adipex-P, Oby-Cap, Suprenza, T-Diet, Zantryl)
- benzphetamine (Didrex)
- diethylpropion (Tenuate, Tenuate Dospan)
- phendimetrazine (Adipost, Bontril, Melfiat)
If after 12 weeks taking weight loss medication a person has not lost 5% of weight, the drug is unlikely to work and should be stopped.
Nutritional medicine treatment of obesity
Australia ranks as one of the heaviest nations in the developed world. The incidence of obesity in Australia has more than doubled during the past 20 years.
Obesity is a complex, chronic, relapsing condition and, along with ageing, is the greatest causal factor to chronic disease burden in Australia. Australia ranks as one of the heaviest nations in the developed world. The incidence of obesity in Australia has more than doubled during the past 20 years.
Today’s fast-paced style of living means that for many the time spent in the kitchen cooking is very much reduced. You can improve the quality of your grocery shopping and the nutritional value of the foods you buy by creating a shopping list and keeping a well-stocked pantry.
If you are committed to losing weight choose low-fat food items, and fill your kitchen cupboards with a supply of low-calorie basics. Resist the temptation to purchase sugar-laden products and avoid anything that has been deep-fried or requires frying in fat. Leave children at home when you go to the supermarket or better still shop online and enjoy home delivery. This will limit impulse purchases and tantrum when you choose not to buy their favourite chocolate ice cream.
Learn to read and understand product labels and compare fat and sugar content, to improve your choices. The lower the fat, sugar, and calorie content per 100g the better. Australian labelling rules require that companies list total calories per serving size so you can compare the total calories in the product you choose with others similar products. Simply choose the one that is lowest in calories.
In order to assess the nutritional status for an individual and customise nutritional treatment, a thorough laboratory investigation is needed and may include one or more of the following.
Three-hour glucose tolerance test (GTT) and serum insulin
Traditionally, this test is performed by measuring glucose and insulin levels in blood samples collected before and for each 30 min period following oral consumption of 75 gm of a pure glucose solution.
A peak glucose level above 10 mmol/L or a rise in insulin greater than eight times the fasting insulin level suggest either impaired glucose tolerance or hyperinsulinaemia, both of which indicate the patient probably has insulin resistance. A blood glucose level above 14 mmol/L is diagnostic of diabetes.
Doctors sometimes measure glucose and insulin measurement both before and 60 min after a high GI meal, to reduce the need for repeat testing. However, a significant percen¬tage of insulin resistant patients may be overlooked, because of meal variability.
Evidence of reactive hypoglycaemia during a three-hour GTT, indicated by an unduly rapid fall in blood glucose greater than 2.0 mmol/L in any 60-minite period suggests that blood glucose control is impaired. This may be due to rapid glucose absorption, increased intestinal permeability, or increased insulin response secondary to gene-related pancreatic beta-cell dysfunction.
The HOMA-R index is used to diagnose insulin resistance. HOMA-R is derived mathematically from the fasting glucose and insulin levels, but there is some doubt about the significance of the level of correlation, with levels approximating low r-values of 0.5 accounting for only 25% of insulin resistance variation.
The HOMA-R formula is: Glucose (mmol/L) x Insulin (mU/L) /22.5 and HOMA-R values greater than 3.0 suggest insulin resistance.
Lipid profile may show elevated fasting triglyceride level (>2.5 mmol/L), decreased HDL-cholesterol (HDL <0.9 mmol/L in males and 1.1 mmol/L in females), and increased ratio between total cholesterol and HDL-cholesterol (ratio >5).
A glycosylated haemoglobin (Hb-A1c) level greater than 5.5% suggests increased protein glycosylation secondary to free radical damage and chronic or recurrent hyperglycaemia. This indicates the need for improved blood glucose control and increased antioxidant intake.
Total antioxidant capacity can detect oxidative stress in many people with chronic disease. A person with insulin resistance and type 2 diabetes will have antioxidant stress caused by impaired GTH status and impaired utilisation of vitamin E. Recent studies suggest that high-dose vitamin E and lipoic acid supplementation may reduce protein glycation and improve peripheral neuropathy.
Hormone analysis frequently reveals reduced steroidal hormone synthesis, both in insulin resistance and type 2 diabetes, due to impaired metabolism and the inhibiting effect of high insulin levels on enzymes involved in steroid synthesis.
Impaired steroid hormone activity generally results in enhanced production of cortisol and reduced synthesis of the anabolic steroids DHEA, androstenedione and testosterone, thereby increasing protein tissue catabolism, and reducing lean-body mass.
Amino acid imbalance is common on amino acid analysis, in particular circulating serine, alanine and threonine, the gluconeogenic amino acids.