Greens are recommended as a weight-loss food. You might think this is because greens are low calorie. But there’s more to it than that! Yes, greens are low caloric while still being packed with nutrients and other active compounds, however, greens’ effect on weight loss goes beyond just calories. Greens contain nitrites, which have been associated in browning fat cells, meaning converting fat-storing white cells into fat-burning brown cells. This creates extra fat burning and ultimately, weight loss.