The Hackers Diet

source: http://www.fourmilab.ch/hackdiet/

pdf version- Hackdiet.pdf - download the 330 page zip file (its Free!).

book about psychology of loosing and maintaining normal weight. Chapter 10 - 'Perfect Weight Forever' is excellent introduction to maintaining early warning feedback on weight gain.

Thanks Jason Coleman for recommending this book. I found you via Google search for: blogspot "Google 15". Jason Coleman says "The key point to take away from THD’s graphs on metabolism and hunger is that to lose weight you must be hungry.

That’s it. That’s the secret. I’ve done well by changing the way I think about a diet. Instead of trying to game the system by finding foods that I can be sated with but still lose weight, I acknowledge the fact that I’m going to have to make a sacrifice. I have to be hungry to lose weight. And so my hunger becomes a good thing instead of a bad thing.

When I get those pangs in my stomach, I know I’m losing weight and embrace it."

I understood this but Jason puts it very well. However i dont need to get hunger pangs too often - by having a calorie deficit of 3500 calories per week or 500 calories a day I can lose a pound a week. I've shown this to the case by monitoring using Google 15 (and Excel spreadsheet years ago).
By using the trend to adjust food intake, we have implemented a very different feedback system. As weight varies within the 5 pound band around the goal, 150 pounds here, it is subject to only a minor degree of feedback, applied by monthly adjustments to what you eat based on the slope of the trend line. If you choose not to bother with such small adjustments, the floor of the feedback curve from 147.5 to 152.5 pounds will be flat and your weight completely free to vary within that band. Once the trend ends a month outside the 5 pound band but within the brick walls, calorie consumption is adjusted. The size of the adjustment is determined from the calorie excess or deficit indicated by the trend. Thus, when the trend strays outside the band it encounters negative feedback proportional to the calorie imbalance that caused it to diverge. This feedback, shown as a steeper line outside the 5 pound band, should normally return the trend to within the band in short order. If, for whatever reason, the feedback invoked when the band is crossed doesn’t have the intended effect, the trend will sooner or later hit the brick wall.

When this (page 272) THE HACKER’S DIET happens, bang-bang negative feedback is triggered to ensure the trend is quickly reversed and brought back to the goal. Resuming a meal plan already proven effective for losing weight (or adding comparable calories if the trend hits the brick wall below the weight goal), provides absolute assurance the trend cannot slip out of control. This constitutes very strong negative feedback that kicks in when the brick wall is hit, shown by the steep rise in the feedback curve at that threshold.

The rules of the game
The adjustments to what you eat based on the trend’s relationship to the goal weight are as follows.

More than 5 pounds above goal.
You’ve hit the high brick wall. Immediately resume the meal plan you used to lose weight and stay on it until the trend falls to less than the goal weight.

Between 2.5 and 5 pounds above goal.
The trend has risen above the band. Reduce your calorie consumption by cutting out food slightly more than the calorie excess reported on recent trend charts.

Within 2.5 pounds of the goal.
No adjustment is required. You can, if you wish, fine tune the trend by adding or subtracting food equal to the deficit or excess reported in the last month’s trend chart.

Between 2.5 and 5 pounds below goal.
(page 273 PERFECT WEIGHT FOREVER) The trend has fallen below the band. Increase your calorie consumption by slightly more than the deficit reported on recent trend charts.

More than 5 pounds below goal.
You’ve hit the low brick wall. Start with the meal plan you used to achieve stable weight at the end of your diet (see page 250), then add an additional 250 to 500 calories per day. If, at the end of the next month, you’re still more than 5 pounds below the goal, add even more calories to your meal plan.

How can it fail?

From everything we’ve learned about feedback, it should be abundantly clear that there is simply no way your weight can get out of control as long as you keep the feedback this plan provides in effect.

And whatever could possess you to abandon it? A desire to be fat once again? Not bloody likely, especially after you’ve just spent so much time and trouble getting thin! Because it’s too much bother? Preposterous! It only takes 30 seconds a day to log your weight, compute the trend, and plot it on a chart, even if you do it by hand. To avoid restrictions on what you eat? But there are no restrictions, not a single one. All that feedback, the eat watch, does is tell you how much to eat—you eat whatever foods you like, whenever you wish. What you choose to eat can make a difference in how you feel, but it won’t affect your weight.

Will you tire of making the continual adjustments?
Don’t confuse the incremental month to month changes in what you eat based on the trend with the rollercoaster of binge eating and dieting that afflicts so many people. (page 274 THE HACKER’S DIET)

First, as long as your weight never strays outside the 5 pound band, adjustments are completely optional and in any case are tiny: fewer calories per day than a glass of skim milk.

As you monitor the trend month after month, you’ll probably find that before long you don’t have to do any arithmetic or formal meal planning at all. Whenever the trend’s a little above the goal, eat less, and when it’s below the goal, enjoy a little more every day.

It is entirely possible to spend years without ever straying outside the 5 pound band. Will you become frustrated by repeatedly having to cut back calories when you exceed the band or hit the brick wall? Again, no. As you master controlling what you eat, these occurrences will become increasingly rare, but even when it happens it’s not that awful.

Since the brick wall triggers weight loss when the trend exceeds the goal by 5 pounds, you’re never more than about a month from the goal.

In fact, if the diet you use after hitting the wall has a moderate 500 calorie a day shortfall, within three weeks the trend should be back within the band. The only way you can gain back the weight you lost is by deliberately choosing to; by discarding the simple and easy feedback that keeps your weight under control; by taking off the eat watch. The slow creep into snowballing weight gain that is the undoing of most dieters simply cannot happen to you any other way. And if you aren’t already committed to maintaining your weight, wait until you’ve gotten really used to being thin and fit. Then no temptation will induce you to resume the life of a fat person.

(PERFECT WEIGHT FOREVER page 275)
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 92 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

(page 276 THE HACKER’S DIET)

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 (PERFECT WEIGHT FOREVER page 277) 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.

The Hacker's Diet, notwithstanding its silly subtitle, is a serious book about how to lose weight and permanently maintain whatever weight you desire. It treats dieting and weight control from an engineering and management standpoint, and provides the tools and an understanding of why they work and how to use them that permit the reader to gain control of their own weight. The book is intended primarily for busy, successful engineers, programmers, and managers who have struggled unsuccessfully in the past to lose weight and avoid re-gaining it. Computer-based tools and experiments in Microsoft Excel or the Palm Computing Platform are available, as well as an online Web application, but a computer is not necessary to use the techniques described in the book; paper and pencil alternatives are provided.