The list is compiled by an independent panel of 22 experts, including nutritionists, dietitians, cardiologists and diabetologists.
L.A. dietitian Patricia Bannan says diets ranked No. 1 and No. 2 for best overall diets are unknown to most of us - the DASH Diet and the TLC Diet.
"The DASH Diet stands for Dietary Approaches to Stop Hypertension. It was originally developed to lower blood pressure," Bannan said. "The TLC Diet is Theraputic Lifestyle Changes Diet. It was originally developed to lower cholesterol."
In a nutshell, both are heavy on fruits and vegetables and light on saturated fat, sugar and salt. Not exactly sexy, but they work for weight management and overall health.
There are seven different diet categories like best diet overall, best diabetes diet and so forth. This year, a new category was added: the easiest diet to follow. Weight Watchers topped this category, followed by Jenny Craig and the Mediterranean Diet. Slim-Fast and Volumetrics tied for fourth.
"Weight Watchers is a great program because you're eating real foods, and there's nothing that's off, so you can stick with this for the rest of your life," Bannan said.
Weight Watchers also won for best weight loss and best commercial plan.
The experts took a pass on the Paleo or Caveman Diet - based on the premise if a caveman didn't eat it, you shouldn't either.
"The negative of the Paleo diet is that you don't get dairy, you don't get whole grains, and you don't get legumes, so you're missing a lot of nutrients in your diet," Bannan said.
With weight loss a billion-dollar industry, Bannan says before you buy your next book, keep a few things in mind.
"You want to have a plant-based diet, lean protein and get some exercise," she said. "There's no cookie cutter plan."
To see the complete list of Best Diets, visit http://health.usnews.com/best-diet.