Generally speaking, most people who worry about being overweight do so not out of concern for their health but because of the cosmetic and social disadvantages of being fat.
This is ironic considering the growing body of scientific evidence that points to the harmful medical and psychological consequences of overweight and obesity. The following risks and conditions have been associated with the problem:
- hypertension
- high blood cholesterol levels
- increased risk of cardiovascular heart disease and diabetes mellitus
- impaired lung function
- gall-bladder disease
- cancer
- osteoarthritis
- reproductive system abnormalities
- psychological disturbances
Quite a list with which to burden yourself! So it's not surprising that experts maintain that the obese tend to have shorter lifespans than people who manage to keep their weight at low-risk levels.
Researchers have also established that it is not only the amount of excess fat you carry, but where you carry it that can put you at risk of developing certain illnesses and conditions. Some people's extra weight settles around their middles (referred to in medical terms as `android fat distribution'), giving them what is commonly referred to as an 'apple' figure. Others carry the weight around their hips (gynoid fat distribution or 'pear' figure). Apple figures occur more often in men (although they are found in women too); pear figures are far more common in women than in men.
For several reasons relating to metabolism, the 'apples' are at higher risk for the development of cardiovascular heart disease and diabetes mellitus than the 'pears'. So anyone who is overweight and has an android fat distribution should be even more concerned about his or her weight.
What makes fat people fat?
After a great deal of research in this field, the experts finally agree that people become fat because of an imbalance in the following simple equation:
energy in = energy out + energy stored
This imbalance can be brought about by various factors which could increase energy intake and/or decrease energy expenditure.
Scientists agree that overweight or obesity is rarely caused by a single factor. In order to come to grips with a personal overweight problem, however, it is necessary to realise that the over-riding cause is an energy intake which is higher than energy expenditure.
Energy expenditure is something which varies considerably from person to person. These variations are part of the reason why some people appear to be able to eat more than others but gain less weight. The three, main factors which influence energy expenditure are:
- Metabolic rate, which contributes approximately 73% to total expenditure and is influenced by factors such as age, sex, fat free (muscle) mass, body surface, hormonal secretions, etc.
- Physical activity, which contributes between 12 and 30% to total energy expenditure.
- Thermogenesis (see below) which contributes approximately 15% to total energy expenditure.
This last component has recently been the focus of a lot of obesity research. The term refers to heat produced in the body in response to cold, or to excessive food intake, especially carbohydrates. Theoretically, thermogenesis enables a person to eat as much as he or she likes without gaining weight, because excessive energy is 'wasted'in the form of heat. In the early 1920s this phenomenon was described as 'luxusconsumption'. An inability to 'waste' energy in this way could ultimately cause obesity, implying that obesity is the result of a metabolic 'fault'.
In an attempt to explain this possible energy-wasting system, various hypotheses have been suggested, ranging from the existence of specialized brown fat tissue which is able to waste energy as heat, to metabolic enzyme cycles - also known as 'futile cycles' - which waste energy. However, no conclusive evidence has been produced to point the 'obesity finger' at any particular mechanism. Even if it could be proved, some people simply have to accept that they need less energy than others to maintain their weight.
Factors that help to make you fat
- Irregular eating habits (skipping of meals, over-eating at other times, over-consumption of specific foods).
- A tendency to resort to food for comfort or in order to deal with other emotions and situations such as frustration, boredom, loneliness, stress, lack of confidence, low self-image.
- Compulsive eating and obsessional thoughts about food and eating.
- Pressure by friends to 'join in and eat' when you are trying to decrease or balance your food intake.
- A tendency to eat not because you are hungry but rather in response to certain external stimuli, such as time of day, the smell and taste of food, the sight of other people eating, the availability of food, the sight of a restaurant or cafe.
- Inability to recognise when you are really hungry and/or when you have had enough.
- A habit of eating fast without really tasting your food.
- A hectic (but not necessarily physically active) lifestyle which includes lots of snacking in place of regular meals.
- Having to attend social, business or other activities associated with eating on a regular basis.
- Frequent, unsuccessful attempts at dieting.
- A sedentary lifestyle with little or no regular exercise.
- Inadequate knowledge of energy needs, balanced eating habits, the difference between good and bad weight reduction programmes, and a healthy lifestyle in general.
- A family history of overweight.
