The Hacker's Diet, as outlined in John Walker’s book, The Hacker's Diet: How to Lose Weight and Hair Through Stress and Poor Nutrition, reduces the issue of weight loss to a simple calculation. Walker states clearly in the opening paragraphs of his book that he is not a doctor, nutritionist, psychologist, sports figure or chef and that his only qualifications for developing this plan are as an engineer, programmer and businessman. He developed this plan for his own weight loss in 1988 and dropped from 215 pounds (97.5 kg) to 145 pounds (65.8 kg) within a year. First published in 1991, The Hacker's Diet is available as a free electronic book.
Walker’s Hacker's Diet, despite its tongue-in-cheek name, takes an engineer’s perspective in approaching weight loss. His plan disregards the complex issues surrounding dieting and metabolism and reduces the issue to a simple math problem focused solely on fuel consumption versus storage. If a dieter takes in less food than is metabolized, stored fat must be used for energy and weight is lost. Walker readily concedes that this method of weight loss amounts to starving and might not be pleasant, but he maintains that a low-calorie diet is essential for fat loss.
Walker’s plan requires that calories are closely tracked and, being a computer programmer, he has made available computer-based spreadsheet tools. Computers are not, however, a required element of the plan, and dieters using the Hacker's Diet also can keep journals with pen and paper, although this method is time consuming. The recordkeeping is meticulous and tracks daily weight, calories eaten and calories burned. Graphs showing progress are produced after the first two weeks, and data from the month-to-month results might direct calorie adjustments.
For Walker, dieting is all about the calories, and while he recognizes the value of good nutrition, he maintains that, strictly speaking, weight loss requires only a reduction of calories and that nutrition is a completely separate issue. He also gives exercise a minimal role, stating that while exercise does increase the number of calories burned, a busy schedule can make regular time for a heavy exercise regimen a virtual impossibility. In the interest of creating a simple program, Walker focused on dieting as the primary method of weight loss.
Some dieters might find the engineer’s approach of the Hacker's Diet to be off-putting. The faithful journal-keeping and number-plugging required by the diet can be wearing, and the book itself, which is dry and technical in places, could discourage potential followers as well. Walker has produced charts listing calorie counts for foods, but accurate calorie counts require that the serving size is known, which can be difficult when dining out. For dieters with a gift for numbers, though, the Hacker's Diet might be the perfect method to control weight.