Food production is a primary contributor to climate change, and one way to mitigate its effect is through consumption choices. Finding the most effective way to achieve emissions reduction via consumers behavioral change has recently raised policy-makers' interest but experimental evidence about this is still scarce. In this study, we examine the impact of individualized information about greenhouse gas emissions on grocery purchases. Using a randomized field experiment, we compare the effects of individualized information on the carbon footprint of grocery purchases to individualized information on grocery spending provided through a smartphone app. Compared to the spending information, the carbon footprint information decreases emissions from groceries by 27% in the first month of treatment, with 45% reductions in emissions from beef, the highest emissions food group. Treatment effects fade in the longer run along with app engagement but persist among those engaged with the app. Our results suggest that the provision of emissions information, in particular when paired with sufficient engagement, is a promising avenue for policies to turn food consumption greener.