You already know that it's important to eat breakfast - it spikes your metabolism, and it helps you eat healthy throughout the day.

Now a new study from the journal Appetite found that there's a specific breakfast ingredient that may help curb hunger all day long: Oat bran.

Researchers gave 30 healthy, lean women four variations on biscuits and juice on separate days. Some were fortified with more oat bran than others, while some weren't fortified at all. After eating each breakfast, participants rated their satiety levels.

The results showed that women were the most full after eating the meal containing the most oat bran. Unsurprisingly, meals without any oat bran added left participants the hungriest.

According to researchers, it's the fiber in the oat bran that did the trick. It helps keep you fuller for a longer period of time, so you would eat post-meal. Also, adding fiber to liquid drinks - like juice - may keep you more full than adding fiber to solid foods.

To get your fill, eat anywhere between four and eight grams of fiber for your morning meal.