Exercising and eating healthy are not just an individual choice, but influenced by family members, friends, or neighbours. Little is known, however, about colleagues, who are another important interpersonal influence. Many people spend many hours at work, surrounded by mostly the same colleagues, who could therefore significantly shape employees' (un)healthy choices. We studied to what extent colleagues may play a part in one another's eating and exercise behaviours by focusing on two pathways: colleagues can encourage a healthy lifestyle or act as role models whose behaviours can be observed and copied. We used the European Sustainable Workforce Survey, with data on 4345 employees in 402 teams in 113 organisations. We used network autocorrelation models, which resemble regression models, to study to what extent employee encouragement is related to fruit and vegetable consumption, and physical activity. Specific to this type of model is the inclusion of a network correlation parameter which allows for the outcome of an employee to be directly associated with the outcomes of their colleagues. In this way we tested whether colleagues' behaviours were related to one another. We found that employees were more likely to eat fruit and vegetables as well as engage in physical activity when their colleagues encourage a healthy lifestyle. Employees' healthy eating behaviours were positively related to their colleagues' fruit and vegetable consumption, while we found a negative correlation concerning physical activity. Overall, colleagues' encouragement and own healthy behaviours have the potential to contribute to creating a culture of health in the workplace and support all employees in making healthy choices.