Results of a new study show that for people who lose a lot of weight, the best way to keep it off is to follow a diet high in protein and low in carbohydrates.
Protein is found in food such as lean meat and fish, food that has been previously proven to be very good for you.
Carbohydrates are found in foods such as pastas, bread, potatoes and rice.
The massive study was carried out by researchers from the Faculty of Life Sciences (LIFE), University of Copenhagen, and featured participants who had previously been overweight or obese.
Participants were put on one of five diets, with each diet consisting of different amounts of daily carbs and protein.
Those who followed a high protein low carb diet were able to keep their weight off, and even lost a little more after the study period.
The study can be found in the November 25 issue of the New England Journal of Medicine.