Children’s nutrition needs less internet hype and more variety, expert says

A nutrition specialist has rejected claims that Greek yoghurt harms children’s kidneys and warned against applying fasting trends to young people, urging parents to prioritise plain foods, regular meals and variety.

Parents trying to make sense of children’s nutrition online are often met with mixed messages, and that confusion was at the centre of a recent visit to Mérida by Ana Bertha Pérez Lizaur, a health sciences lecturer and national nutrition specialist. In an interview with Diario de Yucatán, Pérez tried to separate evidence from trend-driven advice, warning that social media often amplifies claims about what children should eat without providing the scientific context families need. The broader concern, she said later in a talk at the Universidad Autónoma de Yucatán’s medical faculty, is that the internet now spreads nutrition advice faster than it can be checked, creating what the World Health Organisation has described as an “infodemia”.

One of the claims Pérez addressed was the idea that Greek yoghurt is too protein-rich for children and could harm their kidneys if eaten regularly. She rejected that notion, saying children generally need far less protein than many parents assume. For a child weighing about 20 kilograms, she said, daily needs can be met quite easily with foods such as eggs and a small serving of yoghurt. What matters most, she added, is not whether the product is Greek or regular, but whether it is unsweetened. That distinction is important because many commercial yoghurts contain added sugars, which can make them a less healthy option even when they are marketed as nutritious. Other nutrition summaries also note that Greek yoghurt is valued for its higher protein content, along with calcium, vitamin B12 and beneficial bacteria, but advise choosing plain versions to avoid excess sugar.

Pérez also urged moderation rather than routine reliance on a single food. She said yoghurt can be included in a child’s diet once or twice a week, ideally with fruit, but should not become an everyday breakfast habit simply because it is fashionable. The principle, she argued, is variety: a balanced diet is built on rotating foods rather than leaning heavily on one product, however healthy it may seem. The idea was echoed in the same interview by María Luisa Ávila Escalante, who heads nutrition studies at the university, although Ávila was more sceptical about yoghurt for very young children, saying their digestion is different. Pérez, by contrast, framed yoghurt as acceptable for older children so long as it is plain and used sensibly within the wider diet.

She made a similar case when discussing “chrononutrition”, the popular notion that eating should be tightly matched to sunrise and sunset. Pérez said meals have always had a place in daily life and should follow predictable schedules, especially for children. She warned that prolonged fasting is not suitable for the young and said children should not go more than about 10 hours without eating. In practical terms, that means a child who eats at 7pm should have breakfast early the next morning. For adults, she said, a nightly fast of around 10 to 12 hours can be reasonable, but the advice should not be applied wholesale to children. Nutrition research on chrononutrition generally supports the value of regular meal timing and suggests that eating earlier in the day can help metabolic health, but it also stresses that the approach is about rhythm and consistency, not rigid rules or deprivation.

Pérez’s wider message was less about banning foods than about restoring common sense to family mealtimes. She told students and attendees at her lecture that the rise of search engines, social media and algorithm-driven content has made it easier than ever to encounter nutrition claims that sound scientific but are not necessarily well founded. Her advice to parents was straightforward: check the quality of the information, look beyond marketing language and focus on simple, varied meals that fit a child’s age and needs. For breakfast, she said, eggs remain one of the most practical options because they are quick, affordable and versatile. In a food environment crowded with health promises, her central argument was that children do not need the latest fad; they need regular meals, sensible portions and less sugar.