Proportional feedbag

The only ongoing irritation in managing your weight is planning meals and calculating calorie intake. As you gain experience in keeping your weight within the band and confidence in your ability to do so, you will eventually be able to extirpate this lingering annoyance from your life.

The actual number of calories you eat and burn every day, while interesting to know, doesn't really matter. Only the balance between calories in and calories out, expressed by the difference of these quantities, affects the rubber bag. That's why the block in the diagram of the eat watch on page that controls the Eat! signal subtracts calories burned from calories eaten. To keep your weight within the band, all you have to do is keep calories in balance: the result of the subtraction at zero.

After several months of planning meals and adjusting calorie content up and down to stabilise the trend, you may find you're developing an excellent sense of how many calories different foods contain and, more importantly, how much and what kinds of food are appropriate at each meal. You're still planning meals but you're doing it subconsciously, all in your head. In effect, you've advanced from planning meals by counting on your fingers, adding up tables of calories and carefully measuring food, to doing sums in your head. No longer will you look at a bowl of mashed potatoes and think ``137 calories a cup.'' Instead, you know that a dollop the size of a baseball with gravy on the top is about right along with a drumstick of broiled chicken and an ear of corn on the cob. Through carefully planning meals, you've taught yourself by practice and repetition, the only way humans ever learn anything, how to gauge the proper amount of food at each meal.

You're not relying on your appetite; it's still broken, in all likelihood, and shouldn't be trusted in any case. You're using your eyes to measure what your stomach can't: how much to eat at a sitting. After a year of stable weight, you will probably have become sufficiently accomplished at this skill so the only time you resort to a calorie table is upon encountering new food items, to find something comparable among the foods you regularly eat. As you practice the skill of planning meals by eyeball, the trend provides constant guidance. Any tendency to err in either direction quickly manifests itself in a rising or falling trend, which not only tells you there's a problem but how many calories you're high or low. Further, the band and the brick wall protect you during the transition from formal meal plans to your own judgement. If you try to dispense with meal plans too early, the trend will let you know by exceeding the band or hitting the brick wall, and the planning and adjustment required under those circumstances will rescue you before a real problem develops.

In a year or so, controlling your weight like this will seem as easy as riding a bicycle, and something you're no more likely to ever forget. Like riding a bicycle, it was far from easy to learn, but hard-won skills tend to be the most enduring. Unlike a bicycle, no matter how skilled you become in managing your weight, you need never remove the training wheels. Every day you continue to log your weight, every month you compute and chart the trend and make any necessary adjustments, and every year you add another dozen charts of stable weight to your ever-growing archive. When people ask ``How do you manage to stay so thin?'' you can answer honestly, ``Simple, whenever I start to gain, I eat a little less. Whenever I start to lose, I eat a little more.'' Simple, indeed. But, as we've learned from our long and arduous journey through the wilds of engineering and the swamps of management, from pounds of fat and thermostats, and rubber bags and things, simple does not mean easy.