The diet debate has been going on for years now:  Atkins, South Beach, Zone Diet versus the traditional low-fat, low-calorie diets.  At least two out of every three patients that walk through the office I'm at get the nutrition lecture.  But my preceptor doesn't give them the standard low-fat, low-calorie deal; rather, they are urged to get into the "Zone."  The Zone diet is basically a modified Atkins that focuses on an ideal protein/carbohydrate ratio.  The plan emphasizes low-carb, high-protein choices (lean meats, nuts) in addition to fruits, vegetables, and dairy products.  It shuns the high-carb (and low-protein) breads, rices, pastas, and potatoes.  My question is, of course, do the data prove it works?

Well, I couldn't find anything that looked at the Zone diet specifically but a few recent studies have compared low-carb diets to traditional low-fat diets.  Here's one of those studies:  So last year the New England Journal published a study that took 63 obese participants (with no other co-morbidities per se--i.e., they were not diabetics but they probably had some insulin resistance going on) and randomly split them into two diets.  The first group was to eat low-carb, high protein, high-fat foods while the others stuck with high-carb, low-fat, and low-calorie menu options. 

So, what did they find you ask?  Well, the low-carbers lost more weight at the 6-month mark, but by one year the differences were no longer statistically significant.  In addition, the study found that the low-carb peeps also had greater decreases in their triglycerides and greater increases in their HDL (more than could be explained by weight loss alone).  In fact, the traditional dieters dropped their HDLs--a known protector against cardiovascular disease. 

Atkins for everyone?  Well, not so fast.  Following sixty-three participants for 1-year hardly has the statistical power (or something like that) to invert the food pyramid, but at least for the time being I don't have to feel bad about telling our obese patients to reach for the peanut butter and celery instead of the wheat bread.