There's one diet that has people going back to the basics.
A diet of all natural foods, nothing processed no preservatives, no refined sugars. It's the latest craze, but unlike other "pop" diets of the past, this has dieticians smiling.
"It's just no different than what we as dieticians and nutrition experts have been saying for years and years. It's healthy eating," says Dietician Julie Swartz.
Fruits, vegetables, meats, seafood, whole grains, even dairy products... Registered dietician Julie Schwartz says they're all allowed if they're natural and not processed.
"We wouldn't think about putting oil in the gasoline section of the car. Yet we kind of, when we're eating, we put sludge where it should be easy efficient burning gasoline," said Schwartz.
Schwartz says shopping on the outer aisles of the grocery store is the best way to avoid processed foods. And when in doubt, read nutrition labels to make sure your food is chemical-free.
"Think of label reading as a curiosity to empower you with more information. When you look at a label, you're seeing that food, you're seeing beans. So anytime we're seeing something else, we don't really need that in the food," said Schwartz.
This diet is also known as "eating clean." Experts say it works because when you avoid preservatives, added sugar and extra refined flour, you will also avoid eating extra calories.