Key to weight loss could lie within the bacteria in your digestive system.
If you want to lose weight any dietitian will tell you to eat less and exercise more, but researchers say the bacteria in your gut may play a huge role in the size of your waistline.
A recent study published in the journal Nature finds every person carries 160 different kids of gut bacteria.
Some of those bacteria can influence the metabolism by either storing fat or burning less of it.
Other bacteria can slow down food moving through the intestine, so there is more time to grab calories.
What kind of bacteria you have is largely passed down to you, but researchers say the next step is retooling the bacteria in your gut, either through special drinks or antibiotics.
Still, those products are still years away.