Changes in self-reported energy balance behaviours and body mass index during a mass media campaign.

Background: Prevention of (serious) overweight can be achieved by means of small behaviour changes in physical activity and/or diet.

Objective: To evaluate a mass media campaign promoting energy balance behaviours in a Dutch population. Effects were examined for body mass index (BMI) and five energy balance behaviours.

Methods: A representative cohort study of 1200 Dutch adults was employed. Data were collected at four moments. Two campaign waves were launched, following T1 (targeting the general adult population) and T2 [targeting low socio-economic status (SES) men], respectively. Regression analyses were performed to estimate the short-term and long-term effects of campaign exposure.

Results: In total, data of 1030 participants (86%) were available. Time trends showed unfavourable changes in most but not all energy balances behaviour for the total sample. No differences were found for BMI. No differences in the outcome measures were found as a result of exposure to the first campaign (19%). A short-term effect of exposure to the second campaign (29% exposure) was found (T2-T3), but only for low SES respondents, with increases in the attention being paid towards food choice (P = 0.02). At long term, BMI was less likely to increase among exposed people with a non-Dutch ethnicity (P = 0.01, T2-T4).

Conclusions: Exposure to the campaign was low. The first campaign wave had no effects on BMI and energy balance behaviours. Small but favourable changes in attention towards food choice and BMI for at-risk populations were observed among those exposed to the second campaign wave.