Diet, Diet on the Wall, Which Is the Healthiest of Them All?

You may have heard the headlines that screamed out this past week about a study from New Orleans on diet choices. Come on, don't laugh: New Orleans just has a lot of people who need to be on a diet -- so does every city. Even the ones with the lowest obesity rates have rates that are too high for individual energy and well-being, for your country's vitality and for our cost competitiveness with corporations in other countries.

The recent results that grabbed headlines were: Eat more red meat and fat! Low-carb diets lead to more weight loss and better cardiac variables than low-fat diets! The findings were published in a reliable and very respected journal -- the Annals of Internal Medicine. And patients and other caregivers called to ask what they should do or recommend. As doctors, we have to be responsive to the data; science advances and that changes recommendations. Does this change mine?

[Read: Lose Weight in Your Kitchen, Not Your Gym.]

Let's review the facts from the study and other current data, and then reach some conclusions (don't skip ahead). Now we have to get into the weeds to help you (and to guide me) to understand whether this study should change our recommendations or just reinforce them -- or neither. So into the weeds: This study randomly allocated 148 obese, non-diabetics to either a "low-fat" or "low-carb" diet. Among these participants, 88 percent were women and 50 percent were African-American. The low-fat meant that less than 30 percent of their diet was fat, and less than 7 percent saturated fat.

The low-carb diet meant having less than 40 grams of carbs per day -- about 10 percent of a 1,600-calorie diet -- and most of the carbs suggested were complex carbs. All participants were told to avoid trans fat and concentrate on healthy monounsaturated fats. No calorie amount was specified, but each person had 16 nutrition education and assessment sessions over the year and was asked not to change their physical activity pattern. The low-carb group lost about 12 pounds over the year and the low-fat group about 4 pounds, and the low-carb group had better triglyceride and inflammation numbers. The low-carb group ate about 90 calories a day less -- almost exactly totaling to that 8 or so pound weight difference -- but actually ate 30 percent of their calories as carbs, about 40 percent less than the "low-fat" group, and consumed about 40 percent of calories as fat versus 30 percent in the "low-fat" group.

[Read: Carbohydrates: Setting the Record Straight .]

We are left with a number of questions that the study authors probably have the answers to but didn't share in the paper yet -- and they are key for our recommendations to you. The key question I have: Is the reason the low-carb group did better because they ate mainly complex carbs and fewer calories? If so, then our recommendations to you from our website and books should continue as they are and have been -- choose only healthy fats, and avoid simple sugars and foods that rapidly turn into simple sugars. Let me elaborate a little on that today:

If you want a diet that helps you lose weight and is healthy, cutting out a big food group -- such as all carbs or all fats -- isn't best for weight loss and wasn't done in the study. For example, the low-fat group ate 30 percent fat and just 9 percent saturated fat; the low-carb group 40 percent fat and 13.4 percent saturated fat. The saturated fat totals of about 30 percent total fat is much less than the typical American diet. The low-fat group didn't avoid all simple sugars. And we do not have long-term data on plaque (atherosclerosis or hardening of your arteries) or for health from these new data.

[Read: How to Eat After a Type 2 Diabetes Diagnosis .]

What the new data does is support and add some more data supporting the recommendation that the best diet for weight loss and health is still our Cleveland Clinic GO! Foods, which avoids as much simple sugar (or things that rapidly turn into simple sugar in your blood stream) and aging fats as possible. Just avoid the "Five Food Felons," since they're felonious to your body: simple sugar, syrups and all simple carbs, along with aging (saturated and trans) fats. All else is good. But also remember to do enough physical activity and stress management to help your choice of portion sizes get you to the right weight. All other foods are fine for you. As doctors, we have to be responsive to the data, but these data are supportive of our current recommendations and don't change them at all (at least as of now).

If you want to read about more implementing the Cleveland Clinic's Go! Foods Diet now, it's identical to the one we wrote about in "You On A Diet" -- both the original and revised editions -- but if you wait, we'll give you the essence in an upcoming column.

Thanks for reading. Remember these are the views of Dr. Roizen only and do not necessarily reflect those of any organization that he is or was affiliated with.

[See: Diet Success Stories: Dieters Reveal How They Hit Their Target Body Weight.]

An esteemed authority on health and wellness, Michael F. Roizen, MD, chairs the Wellness Institute at Cleveland Clinic, the first such position at any major healthcare institution, where he actively coaches patients. He is a former editor of six medical journals and has published more than 175 peer-reviewed scientific papers. Board-certified in internal medicine and anesthesiology, Roizen co-founded with Mehmet Oz YouBeauty, a media company focused on helping women lead healthier, more beautiful lives, and RealAge. His RealAge series of books as well as his "YOU" series, written with Oz, are worldwide bestsellers, with four No. 1 bestsellers in the U.S. and No. 1 bestsellers in at least five other countries. Roizen and Oz write a daily syndicated column that appears in over 130 newspapers. Roizen has appeared regularly on Oprah, Today, 20/20 and Good Morning America and has a two-hour, 33-station radio show. He is 67 calendar years of age but his RealAge is 48.7 He routinely tweets the week's top medical stories @DrMike Roizen.