Spicy Reading : Save Time, Lose Weight : DIETS THAT WORK, <i> By Deralee Scanlon with Larry Strauss (Lowell House: $19.95, 279 pp.)</i>

The good thing about “Diets That Work” is that it will save you time and maybe even money if you want to lose weight. Deralee Scanlon has cut through the 17,000--or more--diet programs available and zeroed in on 28 she considers safe and effective. She also evaluates 18 best-selling diet books.

Scanlon is a registered dietitian and diet therapist and writes the weekly column “Ask the Dietitian,” which appears in several newspapers. She believes that diet programs fail those who don’t know what they’re in for. “If you’re an executive with a medical problem who travels and eats in restaurants five days a week,” she writes, “you’ll have different dietary needs and limitations than if you’re a working mother who cooks for her family every night.”

Scanlon believes 90% of the dieters who invest in dieting will fail. And it’s not because the diets don’t work: “It’s because 25 million American women and 15 million American men lose more patience than pounds. They simply become frustrated and give up,” Scanlon writes.

She has already done the dirty work of screening enrollment system diets and group programs such as Overeaters Anonymous, MediBase, Optifast, Jenny Craig, Weight Watchers and Nutri/system, among others. She sorts out the pros and cons and gives an evaluation of their effectiveness and shortcomings so readers can decide which is the best diet for them.

The primary criteria used to access the diets were effectiveness (does the diet enable the dieter to accomplish his or her goal and maintain it?) and adherence to the principles of good nutrition. And not all diets meet the criterion of 100% effectiveness--or, for that matter, of good nutrition.

All you have to do is look at her assessment of Nutri/system to see the problem. Nutri/system has several potential drawbacks (such as reliance on prepackaged foods), which do not enhance the clients’ understanding of the need to take responsibility for one’s food choices. More important, Scanlon warns that a number of people on the program have encountered gallbladder disease and says that a few class action suits are pending.

She qualifies the precaution by pointing out that all weight-loss diets present a risk of gallbladder disease for people who have a lot of weight to lose. “Thus,” she says, “the high number of such cases for Nutri/system may be as much a reflection of the organization’s large enrollment as anything else.”

However, Scanlon feels that the diet does work. Her reason: It allows a dieter the freedom to select from a wide variety of meals and offers financial incentive for success. If you complete the year-long maintenance program without regaining more than five pounds, Nutri/system will reimburse up to half the basic enrollment fee (a refund of $150 to $200). However, if you drop out before reaching weight-loss goal but rejoin within the projected time frame for that goal, the enrollment fee is not forfeited.

A program called Weight to Live is based on a liquid diet high in carbohydrates, which reduces the risk of ketones and other potential side effects. It offers choices that enable dieters to begin taking control of their diet from the start and has lifelong support built into it, something Scanlon believes all programs should have.

Still, Weight to Live has many of the risks of any other very-low-calorie diet. Its major drawback, Scanlon says, is that with only eight sites, it is simply not available to most people.

Weight Watchers is one of the oldest enrollment programs around, founded in 1961 by Jean Niedich, a homemaker who built an empire by selling franchises. Scanlon warns that Weight Watchers is not for the quick-fix dieter, which is good to know. Only those who accept the concept that weight control is an ongoing, long-term problem should apply.

Scanlon gives Weight Watchers an A-plus for teaching weight maintenance skills from the start, enabling dieters to make their own food choices: “Weight Watchers promotes gradual weight loss and inspires new members with its 30-year record of success stories.”

If you’re dying to hear about the potential drawbacks of Weight Watchers, you may be disappointed: “The exercise program suggests but does not require medical supervision. . . . While those who run Weight Watchers meetings are trained in the organization’s procedures, they are not required to have professional degrees, so those with eating disorders requiring psychological treatment may not find it here.”

And, men, be warned: “Since most Weight Watchers members are women, some men may feel uncomfortable in the traditional community groups.”

One of the books described and evaluated is “Count Out Cholesterol,” by Art Ulene MD, known for his medical segments on NBC-TV’s “The Today Show.” The premise of Ulene’s book is to reduce saturated fat and increase fiber in the diet, which Scanlon thinks is good advice--the high-complex carbohydrate diet promotes weight loss and control, which in turn helps reduce cholesterol automatically. “This is not a quick-fix approach,” she writes, “relying on some magic food, such as oat bran. It is a plan designed to become a permanent part of your lifestyle.”

However, Scanlon believes that the book should have had a more comprehensive section about exercise, since it stresses the importance of exercise in elevating HDL cholesterol and in weight control. She also notes an omission and an error in Ulene’s nutritional information, and a lack of discussion about mono-unsaturated fats and their ability to help lower total cholesterol (reflecting the American Medical Assn. view that requires “extraordinary amounts of research before accepting any finding”). Still, Scanlon gives the book high marks for accuracy and comprehensiveness.

Robert E. Kowalski’s “The 8-Week Cholesterol Cure,” based on the author’s own bout with high cholesterol (which led to a heart attack and two coronary bypass surgeries at age 41), got a borderline recommendation from “Environmental Nutrition Newsletter,” but on the whole not a bad review from Scanlon.

However, she writes: “Although most of Kowalski’s suggestions are in the spirit of moderation and pragmatism, his directive to completely avoid cheese is extreme and may be impractical. There are a number of fat-free and low-fat cheeses, that, in moderation, should not obstruct your efforts to control cholesterol.”

Several of the diets, in fact, contain a “second opinion” from respected publications and/or organizations, which can only add to the credibility of Scanlon’s own opinions.

Hardly expected, but certainly welcome, are Scanlon’s remarks on dietary treatments for such common diseases and medical conditions as arthritis, calcium absorption, chemotherapy, cholesterol reduction, diabetes, food allergies, hypertension, hypoglycemia, lactose intolerance, multiple sclerosis, post coronary, wheat intolerance and one of Scanlon’s favorite medical subjects, inflammatory bowel disease (I.B.D.), to which she has devoted an entire book, “The Wellness Book of I.B.D.” (St. Martin’s Press: 1990).

These medical discussions are almost anti-climatic, but as long as you’re looking for a diet you can use, you might as well take a few minutes to learn about diseases to avoid.