The Food Diary

There is no doubt that keeping a food diary can be a key to losing weight. This has long been the cornerstone of many successful weight-loss programs. Weight Watchers has prescribed the method to its members for years, with great success. I see this in my practice as well, with those who are really honest and take seriously the habit of writing down what they eat enjoying the most long-term success.

While Weight Watchers has long gotten good results from this approach, not until recently has there been solid scientific evidence to prove that it actually works . Part of the problem has been the long-standing issue of "under-reporting," or the idea that folks are simply not honest about what they actually eat. Research has been mixed, but much of it shows this to be the case, with between 25 and 50 percent of people recording less than they actually consumed. You might think that technology would help, but results are also inconsistent.

In one study (J. Am Diet Assoc 2006; 106: 1256-1259) participants used personal digital assistants (PDAs) to help them keep track of what they ate.

Just as with paper diaries, researchers found that there was a marked difference in the amount of food reported and what was actually consumed. Forty-one percent of the participants under-reported their intake. While the PDAs didn’t help improve the accuracy of the diaries, investigators suspected that the technology itself might be posing a barrier. A common complaint was that the users were not familiar with computers and found the Palm difficult to use.

The technology has, however, advanced by light years since that research was done, and there are more and more websites that offer not just food tracking software but also community support. Such is the model that is offered on LiveStrong.com via the DailyPlate software.

A report in JAMA showed how well such online software works. (2008; 299(10):1139-1148) After an initial weight-loss program lasting 6 months, participants were randomly assigned to one of three groups: some had no special assistance in weight maintenance, others had brief monthly consultations with an expert, and still others enjoyed unlimited access to an interactive website designed to help with weight-loss maintenance.

All three groups regained some weight during the maintenance phase of the trial, which lasted for another 30 months. But over 2/3 of the people in all three groups kept their weight lower than it had been before starting on the plan. However, the amount regained varied according to the group they were in: Those with no special assistance regained the most (just over 12 lbs.), while those in the website tracking plan regained the least (just under 9 lbs.).

In a study that looked at different aspects of weight loss, using a food diary was shown to be as significant as exercise (maybe a bit more) to participants' long-term success. (Am J Prev Med 2008; 35(2):118 –126) Those in the study who more faithfully kept a food diary lost twice as much weight as those who didn’t. When you consider that keeping such a diary is free and easy and doesn’t take a lot of effort, it should be a powerful tool in your drive to eat healthier.

Timothy S. Harlan, M.D., a.k.a. Dr. Gourmet
Drgourmet.com