This website is accessible to all versions of every browser. However, you are seeing this message because your browser does not support basic Web standards, and does not properly display the site's design details. Please consider upgrading to a more modern browser. (Learn More).

You are here: home > living > health

Consumer Reports rates the new diets

Posted Wednesday, May 30, 2007

e-mail E-mail this page   print Printer-friendly page

June Issue Looks At Three Questionable Dieting Tactics

Yonkers, NY — The June issue of Consumer Reports features an in-depth report on dieting, identifying “The Volumetrics Eating Plan” as the top-rated clinically tested diet plan and “The Best Life Diet” as the top-rated diet book. Consumer Reports also outlines eight winning strategies for losing weight and three tactics that are unlikely to help.

New Diet Plan Winners


Consumer Reports rated eight popular diet plans that have been studied in clinical trials. Ratings are based on adherence to nutritional guidelines (the 2005 U.S. Dietary Guidelines for Americans) and the results of published randomized clinical studies that reported short-term (3-6 months) and long-term (12 months) results and together studied at least 40 subjects per diet.

The top-rated Volumetrics diet employs a strategy of consuming “low-density” foods and encourages dieters to first take the edge off of hunger by consuming a low calorie soup or salad. CR notes that other diets, while not as explicit about employing this promising strategy, recommend ways to reduce calories while consuming larger volumes of food to stay satiated.

While Volumetrics was top-rated, Weight Watchers, Jenny Craig, and Slim-Fast followed closely together. Weight Watchers uses weekly meetings and weigh-ins for motivation and behavioral support for diet and exercise changes. It scored average on weight loss but first in long-term adherence. CR experts found recipes appetizing and fairly easy to prepare. Jenny Craig enlists dieters to sign up for individual counseling and meal plans at company outlets, by phone, or online. A study of client histories revealed high dropout rates, though those who stuck with the plan lost considerable weight. A clinical trial revealed better adherence. The Jenny Craig diet requires minimal food preparation. Slim-Fast is a brand line of controlled calorie shakes and bars, widely available in drugstores and supermarkets. The menu analyzed by Consumer Reports meets dietary guidelines. Clinical studies show above-average long-term weight loss but a high long-term dropout rate.

Diet Books: What the Experts Say


Consumer Reports rated seven diet books in the June issue based on an expert-panel questionnaire and CR’s own analysis of nutritional quality. Unlike the diet plans, the books rated by Consumer Reports have never been put to the acid test of a large clinical trial. “The Best Life Diet” was the top-rated, followed by three closely ranked books, “Eat, Drink & Weigh Less,” “You On a Diet,” and “The Abs Diet.” All the books offered fairly healthful menus. But when the panelists evaluated the nutrition advice, they found noticeable differences in the restrictiveness of various books. They also found variations in the quality of the exercise information and the explanations of the science and nutrition behind the plans.

Eight Dieting Strategies That Work


Consumer Reports highlights strategies based on the latest research and statistics gleaned from the National Weight Control Registry, which enrolls people who have documented that they lost 30 pounds and kept the weight off for at least a year. Here are some of the strategies outlined in the report:
  • Start right: Eating a substantial morning meal is recommended by every diet book Consumer Reports analyzed. Seventy-eight percent of the successful losers at the National Weight Control Registry say they eat breakfast, typically some cereal and fruit.
  • Crank up the activity: Dieters should get off the couch if they want to lose weight and keep it off. Increasing time spent doing formal exercise and activities such as housework and yard work will help burn calories.
  • Fill up on low-density foods: One way to spare calories and still eat a satisfying amount of food is to focus one’s diet on foods that have fewer calories per bite. The “Volumetrics” diet, which finished at the top of the Consumer Reports ratings, is based on this strategy.
  • Bring back the scale: Dieters who stay vigilant about their weight can make quick corrections before the pounds add up. While many of the books reviewed discourage the practice of frequent weighing in, 75 percent of the members enrolled in the National Weight Control Registry weigh themselves at least once a week.
  • Bore yourself thin: This approach is outlined in “The South Beach Diet,” “The Sonoma Diet,” and “Ultra Metabolism.” Since variety stimulates the appetite, the more monotonous one’s diet, the less one will eat. People should steer clear of buffet tables, which can be a dieter’s worst enemy.

Three Diet Doubtfuls


Consumer Reports informs readers about these dubious tactics, which, though hyped, are unlikely to help:
  • Diet pills: Weight loss pills have a discouraging track record. “Fat burners” such as amphetamines and ephedra have been linked to heart palpitations, strokes, heart attacks, and deaths, even in healthy people.
  • Angel and devil food: Though it makes sense to purge one’s diet of junk food, there’s no evidence that the presence or absence of any individual food will make or break a diet of the right calorie level.
  • The glycemic index: Research studies have reached conflicting conclusions about whether cutting the glycemic load of a weight-loss diet actually improves results.

 

SuccessFUL LOSERS

The basic formula for losing weight has not changed: Consume fewer calories than you burn--about 500 fewer every day, to lose about a pound a week. Not an easy task, however, or why would legions of people try, fail, and fail again in their weight-loss efforts?

But it’s not impossible. The Consumer Reports National Research Center’s survey of CR subscribers, published in June 2002, found that 25 percent of respondents who had ever tried to lose weight did shed at least 10 percent of their starting weight and kept it off for a year or more.

Successful dieters are finally getting a little attention from scientists, who are examining what those people do to control their weight. This is a welcome change from the many decades of weight-loss research that consisted of scientists coming up with low-calorie, low-fat diets and proving that they would work if people followed them strictly. That was the rub, of course. Most people could not follow them strictly for very long. Pioneering researchers are now seeking practical ways to help dieters feel full without consuming too many calories.

These efforts have begun to produce practical, evidence-based tips for do-it-yourself dieters who are attempting to lose weight on their own, without the help of any formal program or counseling. None of these will work for everyone, but you should be able to find some that will work for you.

1. Start right

While dieters might prefer to save calories by skipping breakfast, eating a substantial morning meal is recommended by every diet book we analyzed. Seventy-eight percent of the successful losers at the National Weight Control Registry say they eat breakfast, typically some cereal and fruit. The Registry, which enrolls people who can document that they have lost more than 30 pounds and kept it off for at least a year, has more than 5,000 members.

2. Choose (and limit) your fats

Many diet experts have backed away from avoiding fats, though this traditional approach is still used by very low-fat plans such as Dean Ornish’s “Eat More, Weigh Less” and the diet endorsed by the Pritikin Longevity Center. Some research shows that a very low-fat diet can slow the progression of heart disease and breast and prostate cancer. But the dropout rate from that type of diet is high.

Scientists now distinguish good fats from bad, based on copious evidence about their effect on blood cholesterol. Most of the popular diet books we analyzed warn against eating “bad” fat, including trans fats created when vegetable oil is hydrogenated, and the saturated fats from meat and dairy sources. Good fats include olive and other monounsaturated oils, nuts, avocados, and omega-3 oils from seafood and plant sources.

But good or bad, all fats have big calorie counts. They contain 9 calories per gram, compared with 4 per gram for carbohydrates and protein. The diet menu in “Eat, Drink, and Weigh Less” recommends liberally consuming healthy fats. But when we analyzed the meal plan, it totaled 1,910 calories per day, about 40 percent of them from fat, which would make weight loss unlikely for many people.

3. Eat healthfully--but sparingly

Backed by a growing body of research, nutritionists have come to a rough consensus on what a truly healthful diet looks like: Eat plenty of fruits and vegetables, and some lean meat and fish, healthy fats, and whole grains. And minimize refined grains, potatoes, full-fat dairy products, and added sweeteners--especially in the form of soft drinks. Studies of large populations the world over have shown that this diet reduces the risk of heart disease, diabetes, and certain cancers.

With minor variations, all the diet books we evaluated recommended some version of this eating plan--and their uniformly high ratings for nutrition reflect that. But they didn’t seem “willing to emphasize calories, or tell people to ‘eat less,’” said Rena Wing, Ph.D., a professor in the department of psychiatry and human behavior at Brown University’s medical school and a founder of the National Weight Control Registry.

The bottom line is that no matter how “healthy” your diet is, you still have to restrict quantities to lose weight. “The Best Life Diet,” which got top marks from our reviewers, provides detailed instructions on proper serving sizes for many different types of foods.

4. Crank up the activity

To control weight from exercise alone requires a devotion that few nonathletes can summon: 60 to 90 minutes a day of moderate to vigorous exercise. But increasing the time you spend out of your chair--in formal exercise and activities such as housework and yard work--helps you burn at least some calories. And an active lifestyle will help you maintain your weight loss. National Weight Control Registry participants report doing about an hour a day of moderate-intensity exercise, like brisk walking. Of the books we evaluated, “You on a Diet,” “The Best Life Diet,” and “The Abs Diet” got high marks for their clear and detailed sections on exercise.

5. Consider cutting carbs

Virtually all diets restrict or eliminate “bad” highly refined carbs such as white bread, cookies, chips, and soft drinks. But a wholesale cutback on grains, fruits, and the sweeter vegetables, such as beets and carrots, was first popularized by the Atkins diet. Recent research has found that for up to a year, some people can indeed safely lose weight on Atkins. In the most recent study, published in the March 7, 2007, Journal of the American Medical Association, 311 overweight women were randomly assigned to one of four diets: Atkins, Zone, Ornish, and a control group on a traditional low-fat menu plus various behavioral strategies. On some measures, Atkins dieters came out ahead. “They had better triglyceride lowering than Zone dieters, better HDL raising than Ornish, and better blood-pressure lowering than all three,” said Christopher Gardner, Ph.D., assistant professor of medicine at Stanford University, director of the study. But while Atkins dieters lost modestly more weight than Zone dieters, at 12 months their weight loss was similar to those on the Ornish or control diet.

Very low-carb diets are not for everyone. As Gardner points out, at least some participants lost 30 pounds and kept it off for a year on all the diets in the study. Successful losers in the National Weight Control Registry overwhelmingly report that they consume plenty of carbs while restricting fat and portions.

6. Fill up on low-density foods

One way to spare calories and still eat a satisfying amount of food is to focus your diet on foods that have fewer calories per bite, or low “energy density.”

Starting your meals with a low-calorie soup or salad and eating main dishes that are full of vegetables and fruits are the main tactics of the low-density diet.

Using government food consumption surveys, researcher Barbara Rolls has shown that people who eat a low-energy-density diet consume hundreds fewer calories per day than those with a high-density diet, yet eat a greater amount of food. And in research on volunteers in her Penn State lab, Rolls has found that consuming a low-density diet helps people lose weight and keeps them thinner. “Volumetrics,” based on this research, has now been studied in clinical trials and finished at the top of our diet Ratings.

Whether they say so explicitly or not, many of the other diets and books we evaluated recommend strategies to reduce the energy density of food. People on the Weight Watchers point system, for instance, soon learn that if they spend too many of their daily point allotment on calorie-dense foods, they’ll go to bed hungry. “The Sonoma Diet” sternly limits dieters to no more than 3 teaspoons of olive or canola oil per day but permits unlimited quantities of low-calorie-density vegetables such as broccoli, spinach, and tomatoes. The Ornish diet, which bans fats almost completely, had the lowest energy density of any that we studied.

7. Bring back the scale

Many of the books we reviewed discourage the practice of daily, or even weekly, weigh-ins, at least in the initial stages of a weight-loss diet. But 75 percent of National Weight Control Registry members weigh themselves at least weekly. “They remain vigilant about their weight loss,” Wing said. “It seems likely that if they gain a pound or two, they take steps to lose it before it can accumulate.”

8. Bore yourself thin

Though many books promise readers they’ll be eating a huge variety of foods, in practice they limit variety of high-calorie foods. “The South Beach Diet,” “The Sonoma Diet,” and “UltraMetabolism” were especially restrictive in their severe initial phases.

Since variety stimulates the appetite, the more monotonous your diet, the less you’ll eat. So steer clear of buffet tables, which can be the dieter’s worst enemy.


Consumer Reports is available at newsstands beginning on May 8th. Portions of the diet report are available for free online at www.ConsumerReports.org.
 
e-mail E-mail this page
print Printer-friendly page
 
 
 
Consumer Reports rates the new diets
Consumer Reports rated “The Volumetrics Eating Plan” as the top-rated clinically tested diet plan.
Latest articles in Health
 
ShopSmart’s secrets for sunburn relief
 
ShopSmart reveals the real deal with vitamin D
 
 
 
Living

Got Feedback?
Send a letter to the editor.

Subscribe
Sign up for the Chatham Chatlist.

Advertise
Promote your brand at chathamjournal.com.



Subscribe now: RSS news feed, plus FREE headlines for your site