The rise of AI-generated diets is changing the way many young people relate to food. It's becoming increasingly common to send a quick message to a chatbot on your phone, rather than booking an appointment with a nutritionist, to design a weekly menu or indicate how many calories to consume to lose weight.
This trend, which is growing worldwide and is also beginning to be seen in Spain and other European countries , is raising concerns among endocrinologists and registered dietitians. The promise of quick results, the pressure to conform to beauty standards on social media, and the accessibility of AI tools intersect with a particularly vulnerable stage of life: adolescence, when the body is still developing and any nutritional imbalance can have lasting effects.
AI-powered diets: a new shortcut to weight loss among teenagers
In our daily lives, mobile phones have become constant companions . They're the last thing we check before going to sleep and the first thing we see upon waking, and this space has become increasingly filled with inquiries about diet, weight, and physical appearance. What used to be discussed in a healthcare professional's office is now asked of an app, a search engine, or directly to an artificial intelligence system.
A recent study from Atlas University in Istanbul , published in the journal "Frontiers in Nutrition," analyzed meal plans generated by free versions of five widely used AI models for adolescents. The result was clear: these systems significantly underestimated the energy needs of young people, proposing diets with around 700 kilocalories less than recommended for their age.
This calorie reduction is practically equivalent to skipping almost a full meal a day . Furthermore, the suggested menus showed an unbalanced distribution of macronutrients: they tended to increase protein and fat intake while reducing carbohydrates below the recommended levels for a growing body.
Among Spanish specialists, the phenomenon is also beginning to be detected in consultations. Ana Isabel Sánchez Marcos , a member of the Management Committee of the Nutrition Area of the Spanish Society of Endocrinology and Nutrition (SEEN), acknowledges that it is increasingly common to hear expressions such as "I follow a diet created by an AI ," especially among teenagers who are influenced by viral challenges, influencers , or forums on social media.
Driven by beauty standards, fitness culture, and the immediacy of the internet , young people are turning to apps that promise to precisely adjust calorie intake, calculate the "ideal calorie deficit," or design express weight loss plans in just a few days. The problem arises when these apps don't take into account the overall health of the person using them.
The risk of "one size fits all" in nutrition
One of the points that most worries professionals is that many AI-powered diets operate with a "one size fits all" logic: based on a few basic data points —age, weight, height, weight goal— recommendations are generated that seem personalized, but are actually based on averages and standard formulas.
Lucía Montini , a nutritionist who analyzes this phenomenon in clinical practice, succinctly summarizes her position: "It is by no means safe for a teenager to follow a diet generated by an AI chat ." She adds that this caution should actually be extended to any stage of life in which specific needs or health problems exist.
During adolescence, the body undergoes growth spurts, hormonal changes, and adjustments in body composition . In this context, a dietary plan based solely on general formulas ignores key factors: pre-existing conditions, medication use, food allergies , intensity and type of physical activity, emotional state, family situation, or even the food culture of the environment in which the person lives.
Montini points out that AI tools typically rely on standardized equations and general databases , without access to actual medical history or physical examinations. Thus, something as simple as not considering medication, kidney disease, diabetes, or an eating disorder can transform a seemingly harmless diet into a dangerous one.
In practice, rigidly following a plan generated by a chatbot without supervision can lead to nutritional deficiencies, hormonal imbalances, or a rigid and unhealthy relationship with food . The apparent accuracy offered by calorie charts or automated calculations is no substitute for a detailed assessment by a qualified professional.
Risks to physical health: undernutrition and micronutrient deficiencies
Beyond theory, data from the Turkish study and experience in European consultations point in the same direction: AI-driven diets tend to cut energy and disrupt essential nutrients , which in adolescents can translate into developmental and health problems in the medium and long term.
Sánchez Marcos warns of the danger of "undernutrition during peak growth" when these restrictive plans are implemented. In other words, a teenager may appear to be at a healthy weight or even thinner, but at the cost of compromising bone mass formation, pubertal maturation, and future metabolic health.
Added to this is the risk of micronutrient deficiencies . Diets that eliminate or excessively reduce certain food groups—whether due to following an extreme fad or a poorly calibrated algorithm—can result in insufficient intake of vitamins, minerals, and essential fatty acids. Calcium, vitamin D, iron, and certain omega-3 fatty acids are just a few key examples for bone development, cardiovascular health, and the hematological system.
In Europe, where there is growing concern about the rise in childhood and adolescent obesity, these kinds of restrictive diets may seem like a quick fix. However, experts remind us that losing weight at any cost is not an acceptable strategy , especially if it means damaging developing structures or increasing the risk of disease in adulthood.
Furthermore, the very configuration of many AI-generated menus reflects popular trends such as the excessive increase in protein and fat at the expense of carbohydrates . This pattern, closely associated with gym culture and the goal of "building muscle," doesn't always align with the actual needs of a teenager who studies, plays sports, grows, and ultimately requires sustained energy throughout the day.
The risk of eating disorders and the pressure of social media
Alongside the physical component, specialists emphasize the psychological impact of AI-powered diets on young people . Adolescence is a stage in which body dissatisfaction, the desire to be thinner, and constant comparison with idealized models on social media are commonplace.
Montini emphasizes that the tool itself is not the problem, but rather its use within a context of aesthetic pressure and excessive control . In boys and girls with perfectionist tendencies, anxiety, guilt about eating, or a tendency towards restriction, receiving automated messages about calories, energy deficit, and target weight can trigger or reinforce an eating disorder.
When a chatbot becomes a kind of "inflexible authority" dictating what, when, and how much to eat , it can reinforce very rigid routines. Breaking a rule due to a social obligation or genuine hunger can generate feelings of failure, guilt, or a need to compensate with even more restriction the next day.
Meanwhile, it's observed that nearly one in ten teenagers has tried weight-loss products without supervision —pills, laxatives, shakes—often inspired by online content. Strict diets promoted by AI, coupled with aggressive advertising of certain supplements, create a breeding ground that fuels the cycle of restriction, binge eating, purging, or compulsive behaviors.
Nutritionists and endocrinologists insist that, in such a sensitive area as our relationship with food, the final decision should remain with the human element . This implies consultations with trained professionals, individualized follow-up, and a perspective that includes both physical health and emotional well-being.
What are young people looking for when they ask AI for diets?
Analysis of search engine trends and chatbot queries shows that the main concerns revolve around three goals : rapid weight loss, localized fat reduction, and muscle gain. This pattern is most prevalent among users aged 18 to 35, but it also appears at younger ages.
Among those who want to lose weight, questions like " how to lose five kilos fast ", "diet to lose weight in seven days" or "cheap weekly keto menu" abound, often accompanied by searches about intermittent fasting and strategies to lose the maximum weight in the shortest possible time.
The section focused on fat loss is filled with technical terms: “ calorie deficit ,” “body recomposition,” “what to eat to get abs.” In the area of muscle gain, questions center on the amount of daily protein, the ideal macros for bulking, or what to eat before and after the gym.
Artificial intelligence tools collect these queries and respond with menus and tables that often reflect fitness culture and fad diets . The risk is that, expecting an immediate and very specific answer, the user loses sight of the complexity of their own health situation and reduces nutrition to a simple equation of calories consumed versus calories burned.
The ease of use of mobile devices and the promise of visible results have turned AI into the “new digital nutritionist” for many young people . But its actual ability to replace professional advice remains very limited.
When AI is useful: organization, not prescription
Despite all the warnings, most experts do not propose an outright ban on the technology, but rather advocate for a more responsible and limited use of artificial intelligence in nutrition . The key lies in clearly differentiating between organizing and prescribing.
Montini explains that, when used properly, AI can be an interesting complementary tool for organizing family meals . For example, it can help plan the week's menu, make better use of what's in the fridge, or provide ideas for varying recipes without always resorting to the same dishes.
Among the uses considered reasonable are:
- Propose weekly menus that are then reviewed and adapted with human judgment.
- Suggest simple recipes using available ingredients at home.
- Offer alternatives to adapt dishes to personal preferences or previously diagnosed allergiesprovided that a professional has previously established the general guidelines.
- Help to develop more structured shopping lists based on the planned menus.
In this approach, artificial intelligence acts as a kind of cooking and planning assistant , but not as the one who decides weight goals, daily calorie intake, or restrictions to be followed. That red line, experts point out, should not be crossed without medical supervision.
Furthermore, it's important to remember that AI models learn from vast amounts of information available online, which is also rife with biases, trends, and content of dubious scientific quality . If the initial data is unbalanced, the responses will tend to reproduce those same imbalances.
Family and professional judgment: irreplaceable pillars
Alongside the technological debate, experts emphasize the irreplaceable role of family and healthcare professionals in building healthy eating habits. In practice, how people eat at home, the messages conveyed about body image and weight, and their attitudes toward food have a greater impact than any algorithm.
Montini emphasizes that professional guidance allows for working not only on "what to eat," but also on the emotional connection with food , fostering a more flexible relationship with it that is less focused solely on weight or calories. Teaching teenagers to recognize their internal hunger and satiety cues is a key part of this process.
For their part, the SEEN (Spanish Society of Endocrinology and Nutrition) and other professional organizations in Spain point out that eating habits are formed in childhood and reinforced during adolescence. These are not changes that happen overnight, but rather a process in which the role of parents or caregivers remains fundamental.
Experts recommend that when a young person shows interest in their diet or body composition , this interest should be used as an opportunity to start a conversation at home and, if necessary, schedule an appointment with a nutritionist or endocrinologist. Bringing questions generated online or by AI to a professional can be a good way to verify information and debunk myths.
Faced with the promise of quick diets, "miracle" plans, or anonymous recommendations on social media, in-person or online consultations with accredited specialists remain the safest option for those who need to adjust their diet for health, sports, or general well-being reasons.
The rise of AI-generated diets is reshaping the nutritional landscape, especially among young people, but data and clinical experience point to a clear conclusion: these systems tend to offer overly restrictive plans, often lacking in essential nutrients and failing to consider individual history. Using AI to help organize menus or inspire recipes can be helpful when combined with sound judgment and supervision, but replacing it with a nutritionist carries serious risks to physical and mental health. Therefore, in Spain and the rest of Europe, expert advice remains firm: when faced with any questions about diet, weight, or performance, guidance from qualified professionals and support from family remain the best safeguard against the simplified promises of AI-generated diets.