Expert: Betul Bilen, Nutrition Scientist, Istanbul Atlas University A study published March 11, 2026 in Frontiers in Nutrition asked five free chatbots to make three-day weight-loss meal plans for four imaginary 15-year-olds (two boys, two girls), then compared the results with plans designed by a dietitian. Every chatbot leaned the same wrong way: too few calories and carbohydrates, too much protein and fat. 'The models differed in many ways. Yet they often produced a similar nutrient imbalance,' said study lead Betul Bilen, a nutrition scientist at Istanbul Atlas University. The gap was not subtle: on average, the AI meal plans had about 700 fewer calories per day than the dietitian's - roughly the size of an entire meal. That matters because, as Bilen notes, 'adolescence is a critical period for growth, bone development and brain development,' and diets too low in calories or unbalanced in nutrients can interfere with all three. This was not the extreme 'super-low-calorie request' scenario that usually makes headlines - the imbalance appeared on ordinary, open-ended prompts too. Teens are a vulnerable audience: nearly two in three U.S. teens (64 percent) report using AI chatbots, and a confident-looking meal plan is easy to mistake for authority. Stephanie Partridge, a public health and nutrition researcher at the University of Sydney, says teens should not restrict their calorie intake 'unless it's in a supervised way with health professionals,' and warns that very low-calorie plans like the chatbots' could put teens at higher risk of disordered eating. Stephanie Kile, a dietitian at the U.S. eating-disorder program Equip, says some of her patients have sided with chatbots over her advice. A chatbot can format a plausible meal plan, but it weighs no health conditions, budget or family context - that is what a dietitian is for. Source: https://www.snexplores.org/article/ai-teens-bad-diet-advice