What to Know About Kids and Nutrition
What we teach our kids about nutrition can impact them for the rest of their lives
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Between finicky eating habits, constantly changing bodies, and a glut of kid-focused food-and-drink marketing, it can be tricky to figure out exactly what (and how much) to feed an active child. We know that children aren’t just scaled-down adults, but research is still sparse in youth sports nutrition.
Solid nutritional research is hard to conduct even among adults, and the challenges are greater with prepubescent kids. The subjects rapidly outgrow specific developmental phases, and the ethics of using children as test subjects—particularly if the eating patterns in question could be unhealthy—are murky, explains Brian Timmons, research director of the Child Health and Exercise Medicine Program at McMaster University. But scientists and nutritionists agree on one major point: how you feed your active child now will impact them for decades to come, both physically and psychologically.
Whether your kids are hiking with you in the backcountry or heading to soccer practice, here’s what you need to know about fueling your mini athlete for optimal adventuring.
Their Healthy Plate Looks a Lot Like Yours
The most important lesson to teach an active child is that food is fuel, says Danelle Kabush, a mental-performance consultant with the Canadian Sport Psychology Association. Timmons explains that eating well for kids looks a lot like it does for adults: lots of vegetables and other whole foods, carbohydrates to support energy expenditure, protein to encourage muscle repair and growth, and fat, because it’s essential to development.
Jessalyn O’Donnell, sports dietitian for Athletics Canada and mother to a very active four-year-old, is a fan of what dietitians call the “athlete’s plate”: a meal with plenty of vegetables, a portion of protein, a grain or starch, and some healthy fats. “Carbohydrate needs should fluctuate according to activity intensity, duration, and type of sport,” O’Donnell says. Protein is still key, but aim for 15 grams per meal rather than the adult-size recommendation of 20 grams. “Fat aligns with general-population recommendations—around 20 to 35 percent of total energy intake,” she says. Don’t get too caught up in measuring macronutrients, though. Use the athlete’s plate as a guideline and you’ll be in range.
Kids Burn More than You Might Expect
Between the ages of 8 and 11, children who spend at least an hour a day moving need around 1,800 to 2,200 calories, according to the USDA. (You can see the recommendations broken out by age and activity level on its website.) Anything more than an hour of daily activity could be considered “heavy training,” which creates a greater caloric need, according to a review published in the Journal of Sports Science and Medicine.
Unfortunately, effort and caloric burn are hard to measure in children. Have you ever taken a ten-year-old on a bike ride? You likely noticed that it took them more effort than it took you to climb a hill, but they might still beat you in a sprint to the parking lot after a quick break. In addition to wild swings in energy expenditure, prepubescent children are burning calories quickly to aid their rapid growth and development, making their needs even trickier to quantify, explains O’Donnell.
Thinking about your child’s nutrition in broader terms, rather than tracking every minute of active play, may be an easier way to ensure that they’re eating enough. O’Donnell typically avoids discussing calories with her patients, particularly children. “Instead I use growth and health markers to determine if total [intake and output] is appropriate.” If you want to know if your child is meeting those markers, talk to their pediatrician.
Kids Use Fuel Differently
Kids naturally burn a higher ratio of fat for fuel compared to adults. “Adult bodies burn sugar first, then fat, then a bit of protein,” Timmons says. “But kids rely more on fat utilization compared to carbohydrates during exercise. In some of our research, we see healthy kids using up to 20 percent more fat than adults.” Timmons believes it may be possible to train the body’s metabolic machinery during childhood, and that eating fat as fuel during endurance workouts as a child could help the body burn fat more efficiently in the future. Metabolic flexibility—the ability to switch between burning carbohydrates and fat as fuel—is a predictor of health, while metabolic inflexibility, conversely, has been linked to type 2 diabetes.
“When you give children an external source of energy, like a sugary sports drink, their bodies suddenly shift to using glucose,” he says. “During a long hike, your kid is largely relying on fat oxidation, so something like trail mix is a better option than a purely carbohydrate-based snack.”
Real, Whole Foods Matter
Kids should avoid supplements of any kind unless prescribed by a doctor. Earlier this summer, researchers found that dietary supplements sold for weight loss, muscle building, and energy were associated with increased risk for severe medical events in children and young adults. Active children still need to replenish muscle glycogen and repair damaged tissue during and after exercise, but a balanced diet of whole foods beats out protein powders or energy gels, according to Timmons. “It’s easy to lose sight of the overall diet when thinking about athletic needs,” he says.
For activities that last under an hour, Timmons recommends making sure that your child has access to healthy snacks with a dose of fat, like trail mix or a peanut-butter sandwich, if they ask for food. On longer days, if you notice they’re not eating and their energy is flagging, set a good example: regularly take bites of whatever fuel you brought along, and encourage them to do the same.
For postworkout recovery, most kids just need a well-rounded meal, says Timmons. If a quicker hit of calories is in order, go for an old-school staple: milk. “We did a large-scale study with milk versus sports drinks for recovery,” Timmons says. “The protein, fluid, carbohydrates, and salt in milk are all great for recovery and muscle repair.”
Hydration Is Simple
Hydration is hugely important for any athlete, but as a parent, your job is simple: offer easy access to water and help your child notice thirst cues. “Thirst is the best gauge for when kids should drink,” Timmons adds. If you’re worried about how much they’re drinking, have them hop on a scale pre- and postexercise. A loss of 2 or 3 percent of body weight isn’t abnormal on a hot day for a hard effort like a cross-country race, says Timmons.
Skip sugary drinks like Gatorade in favor of water or a homemade blend. “There’s certainly a role for sports drinks for an athletic kid expending a lot of energy, especially in endurance sports,” adds Timmons. But watered-down fruit juice with a pinch of sea salt will do just fine.
A Positive Relationship with Food Starts Early
The most important part of childhood nutrition is for kids to develop a healthy relationship with food and their bodies. That education will likely have to come from you, as coaches and teachers aren’t trained to dispel nutritional advice and often accidentally spread misinformation, says Timmons. Even professional athletes can set a bad example: the New York University School of Medicine recently released a statement condemning sports teams’ rhetoric around nutrition, suggesting that most of the sugary food and drink marketed through “multi-million-dollar television and online sports sponsorships” is unhealthy, especially for children.
Kabush explains that she’s also seen an increase in pressure for young athletes to look a certain way, which can lead to unhealthy habits like extreme dieting and binge-eating patterns. “I can’t imagine growing up right now, especially with social media, with the pressure to have a ‘perfect’ body,” Kabush says. When healthy eating isn’t part of a child’s early life, they’re more likely to be swayed by fad diets and unrealistic body-image expectations as they grow up.
“Nutrition knowledge should be a part of a young athlete’s development from an early age,” Timmons concludes. It’s as critical to their mental health as it is to their physical growth.