3. How the Machine Works
The Ultimate Equation
Feeding Your Metabolism
The Weight-Creep Syndrome
Low-Fat Is Not Low-Cal
The Old Binge Weekend
In a Nutshell
4. The Science of Eating
Macronutrients: The Big 3
Using and Storing Energy
Pace Yourself
Always Include Protein
The Right Proportions
The Evolutionary Perspective
The Caveman's Adaptive Mechanisms
The Common-Sense Solutions
The Magic of Fiber
What to Drink?
A Little More Effort
In a Nutshell
5. The "E" Word
Exercise Is Not Just About Burning Fat
Begin by Moving More
Boost Your Metabolism
How Much Exercise Is Needed?
Aerobics or Weights?
Hitting a Plateau
Just Do It - With a Buddy
In a nutshell
6. Tips and Tricks
Emotional Eating
Talk Yourself Out of It
Chew Your Food
The 6-Minute Rule
Get Enough Sleep
Drink Water
Drink Green Tea
Use a Smaller Plate
Weighing Yourself
Manage Your Stress
7. The 10 Golden Rules
Appendix A - High-Fiber Foods
Appendix B - Meal Suggestions
Breakfast ideas
Snacks
Lunches
Suppers
Use your imagination
Appendix C - References
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Using and Storing Energy
The primary reason we eat is to acquire energy. Energy from food allows our organs to function, our muscles to move and grow, our brain to operate and our body to keep warm.
The amount of energy we can derive from food is measured in calories. Some foods provide more calories than others, which is one reason we tend to crave them. Specifically, fat holds more than twice as many calories as proteins or carbohydrates* for the same amount of food, which is why our bodies rejoice at the prospect of receiving fatty foods.
Your organs and muscles obtain energy from the glucose in the bloodstream (blood sugar) which comes mostly from carbohydrates. This process is triggered by a hormone called insulin which is secreted by the pancreas and informs the body that you have received food. The presence of insulin in the bloodstream causes cells to convert glucose into a substance called glycogen which is then stored in the liver and muscles as a short-term "buffer" of energy.
This short-term reservoir can only hold about 300 calories. If there is still any glucose left in the bloodstream after this small reserve has been filled to capacity, your body converts it into fat for longer-term storage. Since there is no limit as to how much glucose can be converted and stored as fat, there is no practical limit as to how obese a person can get.
As the day progresses, energy is used through physical activity and normal metabolic functions (such as breathing, heartbeat and digestion). The glucose required to generate this energy is extracted from the short-term glycogen reserve until it is all used up. At that point, the pancreas secretes a different hormone called glucacon which has the opposite effect of insulin: it instructs cells to convert body fat back to glucose so it can be used as fuel by your muscles and organs.
Those two hormones, insulin and glucacon, are the mechanisms which control the storage and release of body fat and are therefore extremely important in efforts to manage our weight.
To summarize, if you eat more than 300 calories at one sitting, you will be storing some of it as fat. That's not a problem if you are physically active and use up these stored calories later in the day. However, if you have been gaining weight, this is simply an indication that you have been ingesting more calories than were necessary to keep you functioning normally and you have not subsequently converted those temporary fat reserves back to energy through physical activity.
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* 1 gram of fat holds 9 calories; 1 gram of protein
or carbohydrate holds 4.