A parent's evidence-based guide to fueling teen athletes — how many calories they need, the right balance of carbs, protein, and fat, the warning signs of under-fueling (RED-S), and how to build a healthy, lasting relationship with food.
Your teen comes home from practice exhausted, again. They felt dizzy during intervals, they're too tired to finish homework, and they're not hungry at dinner. Maybe you think this is just what being a student-athlete looks like, or that pushing through fatigue is part of getting better.
As a parent, you want to support your teen athlete, but the nutrition advice out there is confusing and often contradictory. Your teen's fueling needs are genuinely different from those of adult athletes. Their body is in a critical stage of growth and development while also training at high intensity, creating energy demands that go far beyond what most people realize [3]. When their energy runs low, the consequences show up in ways that reach well beyond performance [4][6].
In this guide, you'll learn what your teen actually needs to perform and recover, why some of the fueling advice you've heard might be missing the mark, and how to help them build a sustainable relationship with food that supports both performance and well-being.
Why Teen Athletes Have Unique Nutrition Needs
Right now, your teen's body is doing several demanding jobs at once: building bone, growing in height and muscle, and training hard. Adolescence is a critical window for bone development — roughly 90% of adult bone mass is built by around age 18 [1]. Being underweight during these years is itself linked to nearly double the long-term risk of osteoporosis, which underscores how much adequate fueling during adolescence matters for lifelong bone health [2]. For female athletes, the reproductive system is also maturing, and that process depends on having enough available energy [6]. Together, these overlapping processes create energy demands that far exceed what the body needs simply to maintain itself [3].
Here's a frustrating part: much of the foundational sports nutrition research was conducted primarily on male participants, and female athletes remain underrepresented. A large 2025 audit of sports and exercise medicine studies found that women made up roughly 44% of participants overall — but in studies focused on a single sport, only about 20% of participants were women, and very few studies accounted for the menstrual cycle or hormonal contraceptive use in their design [7]. A separate analysis of single-sport research found the same pattern, with women making up only about 20% of participants [8]. This means a good deal of the advice circulating in youth sports wasn't designed with all athletes in mind — especially not female teens.
What Happens When Teen Athletes Don't Eat Enough: RED-S Explained
When your teen consistently expends more energy than they take in, their body can enter a state researchers call Relative Energy Deficiency in Sport, or RED-S (an expansion of the older "Female Athlete Triad" concept that applies to both male and female athletes) [4]. This isn't just about feeling tired — low energy availability can affect many body systems, including bone health, immune function, hormones, metabolism, mood, and cardiovascular health [4][6]. For female athletes, it can also disrupt the menstrual cycle [6].
The tricky part is that these consequences often don't show up immediately, and your teen might even see short-term performance gains before problems appear — which is why under-fueling can deceptively feel like it's "working" [4]. For a deeper look at how RED-S develops and what to watch for, we have a comprehensive guide here.
Sleep and fueling work together to protect your teen from injury. A 2019 meta-analysis of adolescent athletes found that those who chronically slept poorly (often defined as less than about 8 hours per night) had roughly 1.6 times higher odds of a sports or musculoskeletal injury than those who slept well [9]. Layer inadequate fueling on top of short sleep, and the body has even fewer resources to recover and adapt [4]. Stress fractures, frequent illness, and unexplained performance decline aren't always bad luck — they can be red flags that the body is running on empty [4][6].
How Diet Culture Undermines Teen Athlete Performance
Let's talk about something that makes fueling even more complicated: the messages your teen is probably getting about food and their body.
Your teen has likely absorbed messages from social media, teammates, or even well-meaning coaches that equate being leaner with performing better. Maybe they've heard comments about what or how much other athletes eat, or been told certain foods are "bad." The belief that "thinner always equals faster" is one of the most common misconceptions in sport — and while an individualized healthy body composition can matter for some athletes and sports, this idea is frequently overgeneralized into a harmful one-size-fits-all rule [13].
If your teen seems confused, anxious, or guilty about eating, it's not their fault. They're navigating a lot of noise, much of it not grounded in science or in what actually supports long-term performance and health.
Here's what the research actually shows: the leanest athletes aren't necessarily the fastest or most successful. Athletes who under-fuel show measurable declines in endurance, training response, coordination, concentration, and judgment compared with those who fuel adequately, and studies link proper fueling directly to better performance [5]. What drives success isn't a smaller body — it's energy availability, recovery, and mental resilience [5].
How Many Calories Do Teen Athletes Need?
Many teen athletes need somewhere in the range of 2,500–4,000+ calories per day, depending on training volume, body size, growth rate, and sport [3][13]. That's not a typo — and athletes training at very high volumes can need even more. For example, some elite adolescent soccer players have measured daily energy needs exceeding 5,000 calories [3]. These ranges are starting points, not prescriptions; a teen's individual needs depend on their growth, sport demands, and metabolism, and a sports dietitian can help personalize them [3].
Here's what those calories should generally include:
Carbohydrates (about 6–10 grams per kg of body weight per day) as the primary fuel source [4][13]. Carbs power training and help refill energy stores for recovery. Think oatmeal, rice, pasta, bread, potatoes, fruits, and starchy vegetables.
Protein (about 1.2–2.0 grams per kg per day) for muscle repair and growth [4]. Spread it across the day — breakfast, lunch, dinner, and snacks — rather than loading it all at once [4]. Sources include eggs, Greek yogurt, milk, chicken, fish, beans, tofu, and, if convenient, protein powder.
Healthy fats (about 20–35% of total calories) for hormone production, brain function, and absorption of fat-soluble vitamins [4]. Think avocados, nuts, nut butters, olive oil, and fatty fish.
Key nutrients, especially calcium (about 1,300 mg/day for ages 14–18) for building bone [3][12], iron (about 15 mg/day for adolescent girls, whose needs rise with menstruation) for oxygen delivery and energy [13], and vitamin D for bone and immune health [13].
In practice, this means eating breakfast every day — even before early practices — plus regular meals and 2–3 snacks, with some fueling timed around training [13].
As parents, model this yourself. Our own Dr. Erin Ayala starts most days with protein pancakes — not because they're "perfect," but because she enjoys them, they fuel her morning, and they've become a consistent, sustainable part of her routine. That's what good fueling looks like: nourishing, practical, and actually enjoyable.
The Sport Psychology of Fueling: Intuitive Eating and Self-Compassion
Fueling isn't only about physical health — it's deeply connected to mental well-being and performance. When your teen learns to tune into their body's signals rather than override them, they tend to make better decisions, catch problems earlier, and build self-trust.
This is where intuitive eating becomes protective. Across studies, a flexible, permission-based relationship with food (rather than one built on rigid rules and restriction) is associated with less disordered eating and better psychological well-being [11]. Learning to honor hunger, recognize fullness, and eat for both fuel and enjoyment builds resilience that extends far beyond sport [11].
It's worth noting that menstrual irregularities are common among female athletes — systematic reviews report a wide range depending on the sport and how they're measured, with pooled rates of oligomenorrhea (infrequent periods) around 24% and secondary amenorrhea (absent periods) around 16% [10]. In athletes, these disruptions are most often driven by low energy availability, which makes a missed or irregular period an important signal rather than something to ignore [6][10].
Practicing self-compassion around food and the body also helps teens weather the inevitable ups and downs of training. When the inner critic shows up with judgments about eating or body changes, self-compassion offers a way to stay grounded without spiraling into shame or restriction.
How Parents Can Support Teen Athlete Nutrition
If you're reading this, you probably already sense something feels off. Trust that instinct — your teen's body is trying to tell you something important.
Watch your language around food and bodies. Avoid commenting on portion sizes, body changes, or labeling foods as "good" or "bad." Stock the kitchen with a variety of foods and let your teen eat when they're hungry, even if it's not "mealtime." The messages you send about food and bodies matter more than you might realize [11].
Build their support team. Your teen may benefit from a sports medicine physician who understands RED-S, a sports dietitian who specializes in athletes, and a sport psychologist (like the team at Skadi) who understands the pressures they face [6]. Elite athletes have whole teams behind them for a reason, and your teen deserves that same support.
Notice the messages around them. Pay attention to how coaches, teammates, and other adults talk about food and bodies. Comments about portions, body size, or "good" versus "bad" foods often reflect diet culture rather than science [13].
Honor their hunger. If your teen is hungry between meals or after practice, encourage them to eat. Their body isn't trying to trick them — it's communicating what it needs to perform, recover, and grow [11].
Watch for warning signs. Skipping meals, exercising beyond what's prescribed, frequent injuries or stress fractures, or — for female athletes — a lost or irregular period all warrant attention [6][10]. Approach the conversation with curiosity and care, not judgment. Early intervention leads to better outcomes.
When to Seek Professional Support
If your teen is struggling with their relationship with food, feeling constantly exhausted, or if something just feels off, don't wait. Early intervention leads to better outcomes, and getting help isn't a sign of failure — it means you're taking their performance and health seriously.
At Skadi Sport Psychology, our sports-informed therapists and athletic coaches specialize in helping teen athletes and their families navigate these challenges. We understand the unique pressures teen athletes face and can work collaboratively with medical providers and coaches to support sustainable performance and long-term health. Schedule a free discovery call to learn how we can support your family.
References
Coheley LM, Lewis RD. Dietary Patterns and Pediatric Bone. Current Osteoporosis Reports. 2021.
Simchoni M, Landau R, Derazne E, et al. Adolescent Body Mass Index, Weight Trajectories to Adulthood, and Osteoporosis Risk. JAMA Network Open. 2025.
Desbrow B. Youth Athlete Development and Nutrition. Sports Medicine. 2021.
Thomas DT, Erdman KA, Burke LM. American College of Sports Medicine Joint Position Statement: Nutrition and Athletic Performance. Medicine & Science in Sports & Exercise. 2016.
Gallant TL, Ong LF, Wong L, et al. Low Energy Availability and Relative Energy Deficiency in Sport: A Systematic Review and Meta-analysis. Sports Medicine. 2025.
Holtzman B, Ackerman KE. Recommendations and Nutritional Considerations for Female Athletes: Health and Performance. Sports Medicine. 2021.
Ose BM, Eisenhauer J, Roepe I, et al. Where Are All the Female Participants in Sports and Exercise Medicine Research? A Decade Later. The American Journal of Sports Medicine. 2025.
Buehler AE, Bertin KB, Becker B, et al. Gender Participation by Sport in Published Sports and Exercise Medicine Original Research. The American Journal of Sports Medicine. 2026.
Gao B, Dwivedi S, Milewski MD, Cruz AI. Lack of Sleep and Sports Injuries in Adolescents: A Systematic Review and Meta-Analysis. Journal of Pediatric Orthopedics. 2019.
Taim BC, Ó Catháin C, Renard M, et al. The Prevalence of Menstrual Cycle Disorders and Menstrual Cycle-Related Symptoms in Female Athletes: A Systematic Literature Review. Sports Medicine. 2023.
Bruce LJ, Ricciardelli LA. A Systematic Review of the Psychosocial Correlates of Intuitive Eating Among Adult Women. Appetite. 2016.
Vatanparast H, Bailey DA, Baxter-Jones AD, Whiting SJ. Calcium Requirements for Bone Growth in Canadian Boys and Girls During Adolescence. The British Journal of Nutrition. 2010.
Watkins RA, Guillen RV. Primary Care Considerations for the Pediatric Endurance Athlete. Current Reviews in Musculoskeletal Medicine. 2024.
