There are so many on the market today, the decision can be tough to make.
But a new list is out from U.S. News and World Report naming the best diets of the year.
Topping the list of best diets is the dash diet, which stands for Dietary Approaches to Stop Hypertension. It came in number 1 for best diet overall, best diet for healthy eating and for diabetes.
When it comes to heart healthy diets the Ornish Diet came out on top. It's a vegetarian extremely low fat diet that also recommends high fiber foods.
But the big question, what works for losing weight?
Weight Watchers reportedly worked for Jennifer Hudson, and it scored highest on the weight loss diet list. Tying for number two, Jenny Craig, the biggest loser diet and the raw food diet.
It should go without saying but just because one diet works for somebody else does not mean it'll work for you and some of them even come with health risks.
Dr. Louis Aronne is a weight loss specialist at NY Presbyterian Weill Cornell Medical Center.
"People who go on all vegetable diets tend to have thaimine and b vitamin deficiencies," he said.
A vegetarian diet ranked number 10 on the new best diets list. The high protein vegetarian eco-Atkins diet ranked 17.
"People who are on high protein diets ten not to get enough vitamin D and certain water soluble vitamins like vitamin C," adds Dr. Aronne.
And if you have high triglycerides, too many carbs and too little fat can make things even worse.
"If you're on a very low fat diet eating a lot of carbohydrates you can raise triglycerides we see this all the time," adds Dr. Aronne. For more on these diets, go to http://health.usnews.com/best-diet
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