Objective: To examine the exposure to television advertising of unhealthy food among children and adolescents in Beijing, in order to provide a basis for the formulation of marketing management policies with unhealthy food. Methods: Four weekdays and four weekend days were randomly selected during October 19, 2020 to January 17, 2021, excluding holidays and school holidays. The top five popular channels of children and adolescents aged 3 to 18 years old were selected. A total of 720 hours was included for coding and analysis. World Health Organization Nutrient Profile Model for the Western Pacific Region was used to classify food and assess the health level. Results: A total of 13 864 advertisings (ads) was monitored, 38.8% (5 376) of which were food ads. Furthermore, 49.9% (2 680) of food ads were unhealthy food ads, with a frequency of 2.00 per hour per channel. The top five most frequent food ads were infant formula for 12-36 months (26.7%), cheese (16.7%), savory snacks (12.2%), milk drinks (10.5%) and chocolate and candy (6.0%). The most frequently used marketing strategies for unhealthy food ads were brand benefit claims (96.8%) and promotional characters (67.9%). Conclusion Children and adolescents in Beijing are highly exposed to TV marketing of unhealthy foods. Marketing strategies such as brand benefit claims and promotional characters are employed to boost the impact of unhealthy food ads. There is an urgent need to introduce relevant policies to regulate TV marketing of unhealthy foods.

Objective: To investigate the exposure to television advertising of sugar sweetened beverages and the use of persuasive marketing techniques among children and adolescents in Beijing, so as to provide evidence for reduing childrens intake of sugar sweetened beverages. Methods: From October 19, 2020 to November 16, 2021, 32 days were randomly selected. The top four popular channels of children and adolescents aged 3-18 years were defined. Each channel was monitored from 6:00:00 to 23:59:59 for each date. A total of 2 304 h was recorded. Advertisements involving sugar sweetened beverages broadcast before, during or after the program were included. The frequency and the use of persuasive marketing techniques were analyzed. Results: A total of 1 237 advertisements for sugar sweetened beverages were included, of which 50.93% were dairy beverages, 28.38% were teabased beverages, and 19.48% were vegetable protein beverages. The average frequency of sugar sweetened beverages advertisements on every channel was (0.62±1.29)piece/h. The frequency of sugar sweetened beverages advertisements on every local channel [(1.04±1.35)piece/h] and childrens channel [(1.11±1.61)piece/h] was separately higher than every national channel [(0.48±1.24)piece/h] and general channel [(0.12±0.48)piece/h] (t=-14.05, 31.64, P<0.01). There were seasonal differences in television advertising of sugar sweetened beverages, and were more frequent during lunch and dinner times. The most frequently used persuasive marketing techniques were "images of children" (74.54%), "nutritional message" (61.76%), "product composition details" (58.61%), "nutrition claim" (57.24%), and "nutrition function claim or other function claim" (53.11%). Conclusions Children and adolescents are often exposed to television advertisement of sugar sweetened beverages on childrens channels and during meal times. There is an urgent need to formulate relevant policies to regulate the marketing of sugar sweetened beverages advertisement and reduce children and adolescents intake.