OBJECTIVE: To analyze mental distress in relation to participation in lifestyle intervention. METHODS: In 2000-2001 a total of 1948 consecutive participants, living in the suburbs of Copenhagen, were asked to complete a short version of SCL-90-R (anxiety, depression, and somatization) before screening, immediately after screening, and one and 10 months after screening. The screening classified participants into high or low risk individuals. High risk individuals received personal lifestyle counselling and were randomized to either group-based counselling (A) or referred care (B). Multilevel regression models taking into account repeated measurements and missing data at follow-up were performed. RESULTS: Before screening, high risk individuals had higher scores on anxiety, depression, and somatization than low risk individuals. All categories of participants decreased in scores after screening. The scores increased after 1 month, but were still significantly lower than before screening. After 10 months, low risk individuals and high risk individuals in group A still had significantly lower scores (except for depression) compared with pre-screening levels, whereas high risk individuals in group B reached the pre-screening level (except for anxiety). CONCLUSION: Screening for risk of cardiovascular disease followed by health counselling does not give rise to mental distress, but has a temporary beneficial effect.