The Body Mass Index (BMI) makes it possible to evaluate overweight. It is calculated on the basis of weight divided by height squared (W / H²). Let’s take for example a person who weighs 60 kg and is 1.70 m tall : his BMI = 60 : (1.7)² = 20.76 kg /m²
So the BMI enables to give the nutritional status of the patient:
BMI below 18.5 kg/m² → risk of denutrition
BMI between 18.5 and 25 kg/m² → normal weight
BMI between 25 and 30 kg/m² → overweight
BMI between 30 and 40 kg/m² → obese
Obesity and diseases
BMI higher than 40 kg/m² → morbidly obese ( with illnesses secondary to overweight)
Cancers
Breast (after the menopause),Colon,Prostate and Ovarian cancer.
Cardio Respiratory Disorders
High Blood Pressure, Angina, Heart attack, Heart failure,, Sleep apnoea, Asthma
Brain and Nervous System
Strokes, Depression, Anxiety , Low self-esteem and self-loathing
Intestines and associated organs
Acid heartburn, Gallstones, Fatty liver, Cirrhosis, Pancreatic disease, Insulin resistance and Syndrome X
Kidneys and Urinary
Renal failure, Stress incontinence
Metabolic Disorders
Type 2 Diabetes, Raised cholesterol, Raised triglycerides, Lowered HDL fats
Sex and Fertility
Polycystic Ovary Syndrome, Irregular periods, Infertility, Gonadal diseases, Uterine bleeding, Difficult pregnancy with more, complications; including gestational diabetes; hypertension; pre-eclampsia;,early labour
Bones and Joints
Arthritis, Gout
The best way of tackling obesity is to reduce the amount of calories that you eat and exercise more. The is aim of treatment for obesity is to lose weight in order to improve your general quality of life, both physically and psychologically (see the ‘symptoms’ section). For example, losing weight may help you to increase your mobility, or help you to improve your self-esteem (self-worth).
Calorie control
Keeping a food diary can enable you to control the amount of calories that you eat. For example, recording what you eat and when can and help you to identify where you can cut out 500 calories a day from your diet. Keeping a diary may also help to reveal particular times when you overeat, or certain types of food that you are more inclined to binge on.
Try to find other activities to do rather than snacking, such as reading a magazine. Also, be careful not to buy foods that will tempt you, such as high calorie snacks, because not eating these type of foods is an obvious way to cut out 500 calories. You should find that you are still able to enjoy a wide range of tasty options, but in moderation (restraining yourself and avoiding excess).
Avoid special diets. Try to change your eating habits for the long-term by choosing a healthy, balanced diet instead of cutting out particular food groups. See the ‘prevention’ section for more information about healthy eating.
Increase your exercise
If you are obese, in order to lose weight you need to increase the amount of aerobic exercise that you do.
You should aim to do between 45-60 minutes of moderate intensity exercise a day. However, your GP may recommend that you to do more than this (between 60-90 minutes a day) in order for you to lose weight. Before starting an exercise programme, you should check with your GP to ensure that you are doing enough physical activity, and that the activity that you plan to do is safe for you.
In order to lose weight, the exercise that you do should increase your heart rate so that you break into a light sweat and you are out of breath by the end of the activity.
Recommended types of physical exercise include:
· activities that can be incorporate into everyday life, such as brisk walking, gardening, or cycling,
· supervised exercise programmes, and
activities such as swimming, walking (where you aim to walk a certain number of steps a day), and stair climbing.
As well as increasing the amount of exercise that you do, you should also reduce the amount of time that you spend on activities that involve being physically inactive, such as watching television, sitting at a computer, or playing video games.
Children and exercise
Children should be encouraged to do at least 60 minutes of moderate activity each day. The activity can be in one session, or several sessions that last 10 minutes, or more. As with adults, children who are overweight, or obese, may need to do more than 60 minutes of exercise. You should check with your GP before your child starts a new exercise programme.
Control your weight loss
Do not aim to lose weight too quickly, or you could end up losing muscle rather than fat. Aim for half to 1 kg (1 - 2 lbs) per week. This means eating 500-1,000 fewer calories than you were eating and drinking before. You should lose 6-12 kg if you keep this up for three months.
Losing weight and keeping it off is a long term commitment. It is not easy, and it is important not to be disappointed with any minor increases along the way. It is better to look at the overall progress, and remember that any weight loss will improve your health.
Always eat three meals a day, especially breakfast. Do not skip meals, as this will only make you feel hungrier, and it is likely you will overeat at your next meal time. If you are on a calorie controlled diet, remember to reduce your alcohol intake as well.
Weight loss groups
Some people who are overweight, or obese, find that joining a self-help group, or other type of weight-loss organisation, can be a good way of losing weight in a supportive environment.
However, you should avoid groups or programmes that claim to be able to achieve rapid weight loss through the use of ‘crash diets’ because these sorts of programmes have a poor record of success.
Weight loss programmes known to be successful are ones that:
· aim for a realistic weight loss target (usually 5-10% of your original weight),
· aim for a maximum weekly weight loss of 0.5-1 kg (1.1-2.2 pounds),
· focus on long-term lifestyle changes, rather than a short-term, quick-fix approach,
· use both diet and activity as a way of achieving weight-loss,
· promote a healthy, balanced diet,
· promote regular physical activity,
· provide advice about how to change your behaviour, such as keeping a food diary,
· provide advice about how to cope with lapses and possible ‘high-risk’ situations, and
provide on-going support.
Medication
Medication for obesity is only available in extreme cases from your GP. You need to show you can lose weight on a calorie controlled diet before it is considered. Medication is normally one part of a weight-loss programme, and requires a long term change in lifestyle for lasting results.
The part of the brain that controls how hungry we are is called the hypothalamus. It controls the hormones and chemical signals circulating in our blood that influence appetite.
Traditional weight-loss drugs contain amphetamine, which is a stimulant that increases the activity of certain brain chemicals. Stimulants increase the amount of noradrenaline and dopamine hormones in your blood, which stops you feeling as hungry. However, they are not suitable for long term use and can have serious side effects, including high blood pressure, anxiety and restlessness.
Scientists are trying to develop new medications that have fewer side effects by looking at the relationship between your body fat and hunger. Fat produces a hormone called leptin, which makes you feel less hungry.
Orlistat
Your GP may prescribe you with orlistat, which works by blocking the action of body chemicals called enzymes which digest fat. The undigested fat is not absorbed into your body, and is passed out with your faeces (stools). One orlistat capsule is taken with each main meal (a maximum of three capsules a day). You have to have made significant effort to lose weight through diet, exercise or changing your lifestyle before taking it. Even then, it is only prescribed if you have:
· a BMI of 28 or more, and other diseases related to weight, such as diabetes, high blood pressure, or high cholesterol, or
a BMI of 30 or more.
Treatment with orlistat must be combined with a low fat diet and other weight loss strategies, such as doing more exercise.
Treatment with orlistat should only continue beyond three months if you have lost 5% of body weight, and beyond six months if you have lost at least 10% of body weight.
Side effects of orlistat include fatty smelly stools, urgency to get to the toilet, oily spotting on your underwear, and flatulence (wind). Side effects are much less likely if you stick to a low fat diet. Women taking an oral contraceptive pill are advised to use an additional method of contraception, such as a condom, if they experience severe diarrhoea whilst taking orlistat.
Orlistat is not prescribed to:
· pregnant women,
· breastfeeding women, and
children.
Sibutramine
Sibutramine is another type of medication that may be prescribed to help you lose weight. One sibutramine capsule is taken once a day. It affects chemicals in the brain called noradrenaline and serotonin to make you feel fuller, or satisfied with less food. Again, you need to have made considerable effort to lose weight before sibutramine is considered. Even then, it is only prescribed if you have:
· a BMI of 27 or more, and other diseases related to excess weight, such as diabetes, high blood pressure, or high cholesterol, or
a BMI of 30 or more.
Sibutramine will only carry on being prescribed if you lose at least 2 kg within four weeks, and 5% of your initial weight within three months of starting treatment.
People with high blood pressure, heart disease, peripheral vascular disease (narrowing of blood vessels usually in the legs), arrhythmias (abnormal heart rhythms), or a history of strokes, should not take Sibutramine.
Side effects are common (affects 1 in 10 to 1 in 100 people), including constipation, dry mouth, difficulty sleeping, and increased blood pressure.
If either orlistat or sibutramine are prescribed for you, you will also be offered advice, support and counselling about diet, exercise and making lifestyle changes.
Medication and children
The use of medication to treat obesity is usually not recommended for children who are under 12 years of age, unless there are exceptional circumstances, such as their obesity places their life in danger.
Weight loss surgery
People with a BMI of 40, or more, are described as morbidly obese. At this stage, the problem can be very hard to treat. Surgery may be considered to restrict the amount of food eaten, or to interrupt the digestive process.
Surgery may also be an option for people with a BMI of 35 to 40, who have life-threatening cardiopulmonary problems – for example, severe sleep apnoea (a sleep disorder where a person experiences irregular breathing at night), obesity-related heart disease, or diabetes.
Availability on the NHS
Weight loss surgery is usually only available on the NHS where there is a clear clinical need for surgery, and other treatment options have been tried but failed.
You will probably only be able to receive weight loss surgery on the NHS if:
· you have a BMI of 40 or more, or a BMI of between 35-40 and also have a serious health condition that could be improved if you lose weight, such as type 2 diabetes or high blood pressure,
· you have tried all the appropriate non-surgical methods, such as diet and exercise, but have failed to achieve or maintain a clinically beneficial level of weight loss for at least six months,
· you agree to commit to the need for long-term follow-up treatment after surgery at a specialized obesity service, and
you are fit and healthy enough to withstand anesthetic and surgery.
Types of weigh loss surgery
There are three widely used techniques in weight loss surgery:
· intra-gastric balloon.
· gastric band surgery,
gastric bypass surgery, and
Intra-gastric balloon (see Gastric Balloon)
Currently not available in the private Hospitals. An intra-gastric balloon is a soft silicone balloon that is surgically implanted in your stomach. This can help reduce your weight as it then takes less food to stop you feeling hungry. The balloon is usually removed after six months.
Gastric band surgery
Gastric banding is a surgical procedure that involves fitting a band around the upper part of your stomach.
Gastric banding helps you lose weight by limiting the amount of food that you eat.
Once the band is in place it effectively divides your stomach in two, creating a smaller pouch at the top. Having this small stomach pouch will mean that it takes a lot less food for you to feel full. The food then slowly passes down into the rest of the stomach and is then digested in the normal manner.
A gastric band is designed to remain permanently within your stomach. However, it can be removed, and in the majority of cases leaves you with no permanent changes to your stomach. The procedure to fit a gastric band can involve a certain degree of complication, for example there is a risk of infection, and in rare cases, leaking into your stomach may occur.
Gastric bypass surgery cannot be used in people with a BMI of 45 or above, as the risks of serious complications are too high.
Gastric bypass
A gastric bypass is a similar procedure to a gastric band as a band is used to create a smaller stomach pouch. However the pouch is not connected to the rest of the stomach, but surgically re-routed to the small intestine, bypassing the rest of the stomach.
Gastric bypasses have a higher risk of complications that gastric band surgery, but they can be used for people who have a BMI of 45 or above.
Possible complications of gastric bypass surgery include:
· leakage from the intestine or bowel,
· obstructing the bowel,
· internal bleeding,
· blood clots,
· infection at the site of surgery, and
lung infection.
These complications can be serious and may require additional surgery to treat them.
