JUNK food has long been a delectable delight for children the world over. Few kids can resist the temptation of feasting on a bag of potato chips or a chocolate bar flushed down with a can of soft drink.Food experts have for the longest time been cautioning parents to be more mindful of their children's junk food intake. And there's a compelling reason for it.A United Nations Children's Fund (Unicef) study has detected a worrying shift in the diets of Filipino children: they are eating fewer fruits and vegetables, and are getting hooked on foods that are more sugary, salty and fatty. Three-quarters of children ages 13 to 15 eat less than three portions of vegetables a day, while more than one-third drink at least one soft drink a day. The diet shift has resulted in more overweight and obese children and adolescents, the Unicef found.About a third of the country's teenagers could become obese by 2030 if no dramatic intervention is made, the agency warned. Overweight and obesity are defined by the World Health Organization (WHO) as 'abnormal or excessive fat accumulation that presents a risk to health.' Being overweight and obese are part of what the WHO describes as the 'triple burden of malnutrition' affecting Filipino children, along with being underweight and micronutrient deficiency.Medical experts agree that a child suffering from obesity is prone to noncommunicable diseases, such as diabetes, cancer and heart failure. There are social and psychological impacts as well. An obese child could be a target for bullying, tends to underperform in school, has low self-esteem or is likely to develop mental health issues.Curbing a child's craving for junk food is an uphill battle, because it means going up against a huge segment of the food manufacturing industry that caters specifically to nourishing that craving.Because junk foods have a low nutritional value, a typical person could shun them altogether and not miss anything. What junk food manufacturers do is create an imagined need for their products by investing heavily in advertising.Eighty percent of all food advertising in the United States is for junk foods. Over 30 of the top 100 most heavily advertised food products have absolutely zero food value, according to the Raw Food Explained website.The website also quotes Michael S. Lasky, author of The Complete Junk Food Book: 'We are all proselytized at an important age into consuming puppets of the junk food barons. Our parents inadvertently help them by buying their products as a form of 'reward' food. We grow up unaware that we have slowly acquired a junk food habit by the subtle forces of advertising. By the time we are capable of making a decision about junk food, we are already hooked from years and years of indulging in what we had been told by TV was good food.'The Unicef concurs that television and social media advertising and marketing contribute to extreme weight gain in Filipino children.A 2021 study of digital food marketing in the Philippines found that almost all of the social media posts from the country's top 20 most popular food and beverage brands were deemed unsafe for children. These items have levels of sugar and salt that exceed the WHO nutrient profiling criteria, which bans the advertising of such products to minors.That hasn't stopped junk food manufacturers from packaging their brands to appeal to children and using celebrities and influencers to promote them.Unicef stresses the need for a 'whole-of-society effort' involving families and farmers to schools and supermarkets to think up solutions to fight severe childhood weight problems.It suggests front-of-pack labeling of food products to help identify what food and drinks can be marketed to children. Legislation creating a national policy on addressing overweight and obesity that will provide guidelines for the marketing of unhealthy foods and beverages is also nearing approval.But the process must start with the parents. It is up to them to encourage their children to develop healthier eating habits, and protect them from the torrent of commercials that extol junk food.