Dr. Roizen created the RealAge concept and practices at the Cleveland Clinic in Anesthesiology and internal medicine. Dr. Mehmet Oz is a professor and vice-chairman of surgery at Columbia University.

The RealAge test is the unique aspect of this book and website, and the authors' claim to fame. The test provides medically valid metrics that compare biological versus calendar age, based on your answers to the test. The test has received widespread consumer, medical, and scientific acceptance. The test is the thing that differentiates this plan from others. However, the book and the test could just as easily be called: "You: On A Healthy Lifestyle." It goes way beyond diet.

We have to say we are very impressed with the test, as it's one of the most comprehensive health assessments we've ever seen. One of our staffers took the test and at the end received a 9-page detailed written analysis of areas where he was weak, strong, and recommended actions to take to improve his well being (such as don't talk on the phone while driving, take more supplements, only eat one serving of red meat a week, floss every day, etc.). For even more analysis, there are links to other sub-tests for lessening stress, a nutrition analysis, allergies, and more.

You On A Diet stresses the importance of your waist size, not your weight. This is a 14-day "rebooting program" that teaches the how and why to eat and exercise smart. It promises a 2 inch waist loss in 2 weeks. The focus is to help you learn about how the body works, how it reacts to dieting and to become empowered to make the right food choices. Extra weight around the midsection is known to increase risk of heart problems, but it's doubtful that any diet can target a specific section of the body and peel fat away from just that area. When you lose weight, you lose it all over your body.

You eat 3 meals a day plus snacks on this plan. You are cautioned to not buy anything with more than 4 grams of saturated fat or 4 grams of any sugar per serving.

Foods you CAN have include: vegetables and beans, meat and fish, herbs, spices, sauces, eggs and egg substitutes, nuts and seeds, beverages, fruit and fruit juices, breads, grains, cereals, pasta, rice, dairy (milk, cheese, etc.), snacks, sweets, fats and oils. Consequently, not too much is off limits. Have the same foods for each meal (i.e. the same foods for lunch or breakfast each day). Stay away from high fructose corn syrup. Limit simple carbohydrates. Avoid eating 3 hours before bedtime. Exercise is encouraged too: walk 30 min. a day or 10,000 steps, plus 30 min. of strength training a week.

This diet program is not without its critics. Medical and nutrition experts claim that the issue is not just about controlling hunger but dealing with psychological issues such as emotional eating. Also, some say that the downside to this plan is that it generally produces about 10 lbs. of weight loss per year if you change your caloric intake by 100 calories at a time--too slow for many dieters. Yet other experts say that You: On A Diet has no new ideas and little science, just common sense nutrition guidelines, a lot of good marketing and a glowing endorsement from Oprah Winfrey.

The book also places substantial emphasis on the use of supplements. Some also disagree with recommending nicotine patches and caffeine for weight loss.

The website also offers more than 65 interactive health assessments that provide grow younger strategies. These include quizzes and other tools. In the wellness section of the size there are meal planning services. Users of the site can share their weight loss concerns and progress with others via forums, but there is no provision for counseling or feedback via email with health educators or dietitians.

There is tons of information, free assessments, quizzes and articles on the RealAge website, covering more than 40 different topics and conditions, such as: skin care, pain management, back pain, vitamins, sleep, anxiety, first aid, menopause, women's health, migraines, etc. This site is really a mini WebMD. Of course, when you supply your email address, you can opt in to get daily email tips of the day and newsletters from RealAge and their partners. Also, there are about 14 different books and DVDs available from the doctors--not just You On A Diet.

It's clear that RealAge has spent a lot of time and money developing this deep website and levering the book's fame to the max.

The book promotes choosing and eating healthy foods, and eating a well-balanced diet.  The book also encourages incorporating exercise into one's daily routine -- another component of living a healthy lifestyle.  Dieters should consult their physician before beginning any diet plan for guidance on whether it is suitable for you, given your medical history, physical condition, and and medications you may be taking. 

One plus is that the book is backed up by a supporting website, as are many other diet books these days. And, one can find lots of health information about various conditions other than weight loss on the site. There is no subscription fee or cost for using the online service, or getting an in-depth analysis, unlike other diet websites. However, you don't get any kind of email or other feedback from the staff, just other members using the forums.