Obesity

Obesity is one of several major health issues in the 21^st century. It causes a whole range of health problems and in some cases can shorten life expectancy. Diabetes, osteoarthritis, heart disease, cancer, stroke; these are just some of the health problems caused by excess body fat. Obesity is defined as ‘excess fat accumulation which may impair health’. (Source: World Health Organisation: Fact sheets: Dec 2006)

The WHO also defines being overweight as having a BMI of 25 or more, and obesity as a BMI of 30 or more. What is BMI?

BMI or Body Mass Index is a calculation based upon a person’s height and weight which is used to determine if they are a healthy weight or not. Find out more about this in our BMI section. Obesity is often viewed in a derogatory manner but it does not mean a weakness of character. It is easy to be critical of someone who is obese but it cannot always be attributed to poor lifestyle choices. There may be any number of reasons why someone becomes obese.

Causes of obesity

Obesity is a medical condition which can be caused by several factors such as genetics, side effects of certain medications or a medical problem such as an under-active thyroid. Diet and exercise or ‘lifestyle factors’ play a large part and in many ways, are preventable. Many of us lead sedentary lives where we drive to work, sit down at a desk all day and then return home to relax in front of the television.

This combined with the popularity of convenience foods, increased choices at supermarkets and the easy availability of high fat, sugary foods has resulted in an obesity crisis.

Risks of obesity

There are many health problems linked to obesity which include:

• Type 2 diabetes
• High blood pressure
• Osteoarthritis
• Heart disease
• Several forms of cancer
• Sleep apnoea
• Stroke
• Asthma
• Infertility
• Back and/or joint pain
• Impotence

These are the physical aspects of obesity but don’t forget the psychological effects as well which include anxiety, a lack of self-confidence, low self-esteem and depression.

Obesity is a medical condition which can be caused by a genetic factor, medical complaint or a side effect of a particular medicine: however, a major contributor of obesity and one that many of us find difficult to accept is that of consuming too many calories. To put it simply, our calorie intake exceeds our calorie expenditure.

What is a ‘calorie?’

A calorie is defined as a unit of energy. This energy helps to fuel your body so that it can function as per normal. Calories often get a bad press but they are vital to our everyday existence.

We all require a certain amount of calories to ensure that essential organs such as the brain and heart function as necessary. This number of calories varies according to age, gender, level of activity and current weight. Our bodies require at least 1,000 to 1,400 calories to perform a range of basic functions.

The role of calories and weight management

How do calories affect weight loss/gain?

If you consume more calories than you need your body will store these additional calories as fat. This increase in body fat leads to an increase in weight.

But, if your calorie intake is less than your calorie expenditure (in other words, what you burn off) then you will lose weight. This is known as ‘negative calorie balance’. A neutral balance is achieved when calorie intake equals calorie expenditure. If this occurs then you will maintain the same weight. This is something to aim for once you have achieved your weight loss goal through using Alli. Once you have lost that extra body fat (and weight) and are committed to a healthy lifestyle then your aim will be to maintain your current weight. To reiterate: obesity develops over a period of time, usually as a result of poor lifestyle choices such as a high fat diet and a lack of exercise. In some cases, your genes may be to blame. But there are steps you can take to deal with your obesity which include healthy eating, increasing activity levels and minimising alcohol intake. By doing this you will reduce your body fat levels, in particular the amount of visceral fat which can lead to serious health problems.

The dangers of visceral fat

What is ‘visceral fat?’ Visceral fat is the medical term for the layer of body fat which is found within the abdomen that surrounds internal organs such as the liver. We all need a certain amount of visceral fat to operate normally. This type of fat is broken down easily by the body which gives us short bursts of energy when required. But an excess amount of this fat can lead to conditions such as Type 2 diabetes, heart disease and strokes. Too much visceral fat causes an increase in the levels of hormones, fatty acids and proteins into your blood stream which affects the function of many organs, e.g. the heart.

Plus the effects of this can be seen externally as well. Many men with an excess of visceral fat develop ‘abdominal overhang’(also known as a ‘beer belly’) which is often due to the way that they store body fat. It is also caused by a poor diet and a lack of exercise. People tend to fall into one of two categories when it comes to fat storage – ‘pear shaped’ and ‘apple shaped’.

People who are ‘pear shaped’ tend to store extra fat below the waist, usually the hips, thighs and buttocks. Many women are pear shaped. People who are ‘apple shaped’ store fat around their waists. Many men are apple shaped. Visceral fat – also known as ‘intra-abdominal’ fat differs from the two other types of body fat. These are:

• Subcutaneous fat
• Intramuscular fat

Subcutaneous fat is the layer of fat which is found beneath the skin. This is the fat which you can pinch between your fingers. This type of fat has a different role to visceral fat in that it is stored for a long period of time. This is necessary in cases of pregnancy or if someone goes a long period of time without food.

Intramuscular fat is found in skeletal muscles within the body. These muscles are controlled by the immune system and perform a range of movements which include contraction. Too much intramuscular fat may lead to insulin resistance and diabetes.

The amount of visceral fat varies from one person to another. It is determined by age, gender, ethnicity, family history and lifestyle. The more active someone is the more calories they will burn which will reduce the amount of visceral fat within their body. This may sound alarmist but you can reduce your amount of visceral fat by eating healthily, losing weight and taking regular exercise. This combined with Alli will reduce your amount of visceral fat and your weight as well. Obesity is only discussed briefly as part of this Alli guide. If you want to know more about this then visit our obesity surgery guide.

How much body fat do you have?

Find out more about how this can be calculated in our BMI section.