Adherence to diet for a single year, not the particular weight loss plan, is the most important determinant of highly effective weight reduction. Based on the outcomes of a randomized trial published in the January 2005 issue of JAMA. When looking at Atkins, Ornish, Weight Watchers, and Zone diets, the author suggests the "low fad" strategy.

The low Fad Approach

The accessible Fad Approach
Effective weight loss is best achieved by sticking to the low fad approach. The low fad method to losing weight involves reasonable reductions in caloric intake with increased physical exercise. There's nothing "fad" regarding this approach and is supported by a few studies.
The fact that the lower fad strategy is backed by scientific evidence is key...the fad diets already in the market have very little credible proof supporting the promises of theirs.
"The scarcity of data addressing the health effects of diets which are popular is an important public health concern, especially since patients as well as medical professionals are keen on employing popular diet programs as individualized eating methods for disease prevention," write Michael L. Dansinger, alpilean (by latinohealthaccess.net) MD, a Preventative Medicine specialist from Boston, Massachusetts.
Dr. Dansinger passes to say, "Some designs minimize carbohydrate consumption with no extra fat restriction (eg, Atkins diet), several modulate macronutrient harmony as well as glycemic load (eg, Zone diet), and some restrict body fat (eg, Ornish diet)."
Thus, besides the shortage of evidence backing the promises made by fad diet programs, there's no consistency from one diet to another inside the identical group of diet sort. This will make it incredibly hard to study the fad diets and assess the issues on your overall health, not to mention the chances of yours for effective weight reduction.
But there's hope for dieters...the very low fad strategy or "Low Fad Diets."
Profitable Weight Loss...The Evidence Supporting Low Fad Diets

Profitable Weight Loss Conclusion