this is an extract from Jackie's Health & Diet Club Magazine Number One
What is a Calorie?
A 'Calorie' is a unit of energy. One calorie is equal to the amount of energy (or heat) needed to raise the temperature of one gram of water by one degree centigrade. It is, in fact, a very small measure, which has lead to a great deal of confusion, because when people say they're on a so-many-calories-per-day diet, they actually mean so-many-thousand-calories-per-day. A convension has now grown up in the diet trade to spell Calorie with a capital letter 'C' to mean 'a thousand calories'. However on food lables the more accurate term 'kcal' is used, meaning 'kilo-calories' (thousand calories). In this article I am sticking to the convention of using the word 'Calories' to mean 'kcal', because that's what everybody understands and is the way the word is used in almost all the diet books.
The Origins of The Calorie Theory
The human body needs energy: first and foremost, to maintain its body temperature at 36.9 degrees Celsius (98.4 degrees Fahrenheit). When the body is active, additional energy is required to move, to speak, or simply to remain standing in a vertical position. On top of this, more energy is needed to eat, digest, breathe and carry out the basic activities of daily life. The body's daily energy requirements vary with age and gender, and from one individual to another.
In 1930 two American doctors, Newburgh and Johnston of the University of Michigan, put forward the theory that "obesity stems not from a deficient metabolism, but from a diet too rich in calories".
Their theory stated that if an individual needs 2,500 Calories a day and only consumes 2,000, a 500 calorie deficit results. To compensate for this deficit, the body will draw on its fat reserves to find an equivalent amount of energy, and weight loss will follow. If, on the other hand, an individual regularly consumes 3,500 Calories whereas 2,500 would suffice, the excess 1,000 Calories will automatically be stored away in the form of fat. The theory is therefore based on the assumption that there is never any loss of energy; it is purely mathematical, directly inspired by Lavcoisier's theory on the laws of thermodynamics.
At this point, we may ask ourselves how, during World War Two, prisoners in Nazi concentration camps survived for nearly five years on only 700 to 800 calories a day. If the calorie theory was indeed correct, the prisoners would have died once their fat stocks expired - in other words, within a few months. Similarly, we ask ourselves why many hearty eaters who regularly consume 4,000 to 5,000 calories a day never grow fatter - some even remain very skinny all their lives. If the theory held true, these hearty eaters would weigh over 70 stone after only a couple of years! Moreover, how does one explain that certain people put on weight even though they restrict their diet and reduce their daily ration of calories? Statistics actually show that more than 50% of the obese eat less than the average adult. Ironically, this is how thousands of people put on more and more weight while starving themselves to death.
Unfortunately, the Newburgh and Johnston study on energy equilibrium was based on limited observations, and above all had been conducted over a period of time that was much too short to establish any serious conclusions. Despite these weaknesses, the publication of their study received much acclaim and was immediately accepted as an irrefutable truth. Their word has since been considered gospel. Several years later, however, Newburgh and Johnston, somewhat troubled by the public excitement over their discoveries, quietly published some serious reservations they had on their findings. But nobody paid any attention. Today, the conclusions of their initial study remain integrated and enshrined in the curriculum of most Western medical schools.
Why The Calorie Theory doesn't work for you
Restricting your diet to reduce your daily ration of calories will cause your metabolic rate to slow down. This will result in less of the 'spare' calories you eat being 'burnt off' - they'll be stored as fat instead! You could slow down your metabolism so much that you could eat only 600 calories a day and still not lose any weight; you could be obese yet at the same time severely undernourished.
But what is metabolism?
Metabolism is the process of turning the fuel in food into energy that the body can use - and burning off unwanted fat. People vary considerably in their ability to turn food into energy and to burn fat. Those that don't do it well have a slow metabolism and consequently turn more food into fat. Most obese people have slower rates of metabolism than slim people. When you go on a cash diet the body sees this reduction in food as a threat and slows down the metabolic rate by as much as 45%. But the minute you go back to what you were eating before, the fluid returns, and so will the fat because your metabolic rate has slowed down, meaning that you now need less food to maintain a stable weight.
The Low Fat Diet/Rosemary Conley's Diet
The Carbohydrate Addict's Diet/Dr Atkins Diet
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