Introduction.

The ecological footprint left by consumption of food and beverages is an environmental concern in order to achieve longrun sustainable development. The main factor to improve is individual awareness in connection with environmentally friendly consumption habits; however, that connection has some breaks: a gap between habits and attitudes that conditions the final decision results.

Objective.

Analyze the gap between attitudes and habits of young consumers of PET-packaged beverages in the city of Medellin, Colombia, in the year 2016.

Materials and methods.

A quantitative inference study was carried out on a probabilistic model. Three hundred surveys were conducted on young adults in the city of Medellin, and two logistic regression models were used to analyze the cognitive gap between pro-environmental attitudes and habits.

Results.

The results show the presence of a cognitive dissonance that contradicts the theory of rational choice and reaffirms the existence of a gap between attitudes and the effective behavior of the consumer.

Conclusions.

People in the city of Medellín show environmental concern, but they do not actually take environmentally sustainable actions. They present a cognitive gap between attitudes for environmental concern and the habit of recycling.