R&B superstar Usher has adopted a new diet based on his blood type.

The Yeah! hitmaker has tried all kinds of food regimes and fads over the years and he once even hired a professional chef to travel with him around the world as he attempted to stick to a vegan diet.

Laughing at his former extravagant lifestyle, he says, "That was opulent as hell. It was just difficult to find people who can make vegan food taste great."

Now Usher is trying out the blood type diet, which is based on the theory that different blood groups have different nutritional needs.

He tells Billboard magazine, "These days, I try to eat for my blood type when I'm not eating for the fat kid inside me.

"A doctor I know came up with it... But the idea is to eat the foods that work best for your body. For my blood type the meats I can eat are pork, beef and fish."