The Definitive Guide to Children’s Nutrition
Feeding infants is quite simple. There’s a ton riding on you getting it right, of course—a developing immune system, the fact that the kid’s growing an inch a week, a permeable blood-brain barrier, synaptic pruning—but the answer is usually always “feed them more breastmilk.” Even if you can’t nurse, you’ve got formula, which, for all its limitations, is a decent proxy for breastmilk and getting better all the time. Feeding children, however, is a different ballgame altogether.
I’ve gotten a lot of requests for a post about children’s nutrition, so it’s long overdue. When it comes down to brass tacks, kids really are just small people. They aren’t a different species. They use the same nutrients their parents do. They need protein, fat, and glucose just like us. So in that sense, feeding kids is simple: Give them all the nutritious foods you already eat and know to be healthy.
But it’s not easy.
Adults have been around the block. We’ve already spent several decades eating, so what we do today won’t have as big an impact. Kids are starting from square one. They can get away with a lot in the sense that they have fast metabolisms, they heal quickly, and they carry less physiological baggage. That makes them appear impervious to damage. A Snickers bar may very well send a diabetic’s blood sugar to the stratosphere or trigger weight gain in a middle-aged man, while the average toddler will channel that candy bar into pure ATP and use it to scale bookshelves, leap from sofas, and sing the feature song from the latest Disney flick twenty times in a row.
But from another perspective, a child’s nutrition is way more crucial and precarious. You have an untouched, uncorrupted member of the most complex, creative, intelligent, courageous mammalian species in the known universe. A being of pure potential. You have the opportunity to realize that potential by nourishing it with the best food—or you can tarnish it.
A prudent position is the middle one: Feed healthy foods, but don’t flip out because they ate Baskin Robbins ice cream cake at their friend’s 5th birthday party. After all, look at your own history. Many of you spent decades eating the standard American/Westernized diet. You ended up fat and unhealthy. And you and thousands more turned it all around just by going Primal.
With this in mind…
What are some nutrients to watch out for?
CALCIUM
Growing children are constantly laying down new bone. They need calcium (and collagen, but we’ll get to that later) to do it.
RDA: 1000 mg/day (4-8 years), 1300 mg/day (9-13 years)
Bone-in sardines, hard cheeses, raw milk, full-fat yogurt/kefir, and leafy greens are the best sources of calcium.
Suggested recipe: A hunk of Emmental cheese.
IODINE
It’s the most common cause of preventable cognitive disability; nearly a third of 6-12 year olds worldwide eat inadequate amounts of iodine.
Growing children need iodine to produce thyroid hormone, an important regulator of the growth factors that determine mental and physical development. Kids with iodine deficiency are less likely to reach their maximum height, and studies show that iodine deficiency can lower IQ scores by up to 12.5 points.
RDA: 90 ug/day (4-8 years), 120 ug/day (9-13 years)
Seaweed, with kombu/kelp being highest and nori being lower but still higher than other foods. Milk (storage vats are disinfected with iodine).
Suggested recipe: Toasted nori snacks. Kelp granules sprinkled on everything.
IRON
Iron is another important mineral in children’s nutrition, providing support for growth, neurological development, and blood cell formation. Keep in mind, however, that kids between the ages of 4 and 8 actually need less iron than babies, toddlers, and teens because they grow more slowly.
RDA: 10 mg (4-8 years), 8 mg (9-13 years, prior to menstruation for girls)
Red meat, especially organ meats (including chicken liver), is very high in iron. The heme iron found in animal products is also far more bioavailable than non-heme (plant) iron. If you’re going to eat and attempt to absorb non-heme iron, pair it with a source of vitamin C.
Suggested recipe: Chicken liver paté.
ZINC
Zinc is really important for children’s physical growth and immune development. In one study, modest zinc supplementation to the tune of 5.7 mg/day helped growth-delayed kids hit their growth targets compared to placebo. Other research has found that correcting zinc deficiencies reduces diarrheal infections and pneumonia in kids under 5.
RDA: 5 mg/day (4-8 years), 8 mg/day (9-13 years)
Red meat (especially lamb), oysters, crab, and lobster are the best sources of zinc.
Suggested recipe: Place a can of smoked oysters (drained), 8 olives (I like Kalamata), and a tablespoon of avocado oil in food processor or mortar and pestle. Turn into paste. Eat with a spoon or spread on crackers. You can also add lemon juice and pecorino romano cheese for some extra calcium.
Vitamin A
Full-blown vitamin A deficiency can cause night blindness and permanent blindness. Mild deficiency increases the risk of catching an upper respiratory tract infection.
RDA: 400 ug/day (4-8 years), 600 ug/day (9-12 years)
Pre-formed (more bioavailable) retinol: liver, cod liver oil, eggs, full-fat dairy.
Plant vitamin A: Sweet potato, kale, spinach, carrots.
Suggested recipe: Liver pate.
Vitamin B12
Myelin is the protective sheathing around nerve fibers. It insulates the nerves and increases the efficiency of impulse transmission. Vitamin B12 is a vital co-factor in myelination—the laying down of the sheathing—which takes place in infancy and on through early childhood. Without adequate dietary vitamin B12, the myelin will be weak and ineffective.
RDA: 1.2 ug/day (4-8 years), 1.8 ug/day (9-13 years)
Animal products are the best and only sources of vitamin B12.
Suggested recipe: Meat, poultry, fish, or shellfish cooked any way.
Vitamin C
We can’t make vitamin C like most other mammals, so we have to eat it if we want its benefits, which include collagen formation and deposition, tissue healing, and immune response.
RDA: 25 mg/day (4-8 years), 45 mgday (9-13 years)
Vitamin C is present in most fruits and vegetables. If your kid eats plenty of those (what kid doesn’t like fruit?), he or she will be fine.
Suggested recipe: Tall glass of Florida orange juice! Kidding. Some oranges will do.
Vitamin D
If your child is getting unfiltered sunlight on a regular basis, vitamin D probably isn’t a concern. But sometimes the sun’s not out (for months). Sometimes your kid needs to eat some vitamin D.
RDA: 15 ug/day for everyone
Great sources include meat, fish, eggs, and cod liver oil. New research has shown that animal-sourced vitamin D is about 5 times as potent as the vitamin D3 found in supplements (which isn’t too shabby in the first place).
Suggested recipe: Cod liver oil capsules, swallowed whole or pierced and the contents squeezed into smoothies.
Vitamin K2
One way to think of vitamin K2 is that it tells calcium where to go. Low vitamin K2 could mean your calcium ends up in your arteries. High vitamin K2, and it’ll end up in your teeth and your bones. I know where I’d rather have it, especially if I’m an 8-year-old human laying new bone daily.
RDA: Unknown. But it’s quite safe.
Natto is the best source. “Best” as in densest, not “best” as in “tastes great.” The flavor takes some getting used to, but once you do… Other options include goose liver, gouda cheese, and more speculatively, some fermented foods like kefir and sauerkraut. Chris Masterjohn did a whole series on vitamin K2 that contains some food sources.
Suggested recipe: Aged gouda (at least 2 years) on rice crackers or eaten Costanza-style.
CHOLINE
Choline helps the liver process fat and clear toxins, and it’s a precursor to acetylcholine, the neurotransmitter that plays a major role in forming memories and learning new skills.
RDA: 250 mg/day (4-8 years), 375 mg/day (9-13 years)
Egg yolks are pound for pound the best source. Livers of all kinds are runners-up.
Suggested recipe: Scrambled eggs with an extra yolk (creamier).
EPA and DHA
Preformed long chain omega-3s are very important for brain development. That’s been the case in humans for a very long time.
Suggested recipe: Ikura, or salmon roe. Sockeye salmon with crispy skin (fish bacon always lures them in).
SATURATED FAT
A curious thing occurs when a child turns 2, according to the powers-that-be. Saturated fat goes from being an essential, dominant, and healthful component of the breastmilk upon which they rely for sustenance to being a lethal toxin. Parents are urged by many health professionals and public service messages to switch to low-fat dairy at this time, and “When should my toddler switch to skim milk?” is now a common query on children’s health websites.
It’s horrifying.
Our cell membranes are about half saturated fat, which is more stable and less vulnerable to peroxidation. This stability makes our cell membranes more resistant to oxidative stress. Kids certainly need cell membranes.
Our bodies use saturated fats to shuttle proteins between cells, release neurotransmitters, and form memories. Kids certainly need to send proteins around the body, release neurotransmitters, and remember stuff.
Saturated fats often come attached to other nutrients kids inarguably require. The more parents restrict saturated fat in their kids’ diets, for example, the less calcium, vitamin E, and zinc they get. It’s hard to “reduce saturated fat” without also reducing lots of other good foods.
CHOLESTEROL
Cholesterol is another one of those weird nutrients that becomes toxic once you stop getting it from breastmilk. I didn’t buy it with saturated fat, and I’m not buying it with cholesterol.
Parents who follow the official advice and “limit cholesterol” deprive their kids of a vital nutrient responsible for production of steroid hormones and vitamin D. Sure, while a kid’s liver will make plenty of cholesterol on its own, limiting cholesterol means limiting some of the most nutrient-dense foods, like egg yolks and shrimp.
Probiotics and Prebiotics
Ideally, children will get access to plenty of microbes by interacting with the natural world around them. But food-based probiotics are good, too. They provide unique nutrients, as the fermentation process often creates new forms of the nutrients or makes existing ones more bioavailable, and they offer novel flavors that promote a more sophisticated palate. A kid who learns to love kimchi will probably try anything.
Prebiotics are arguably as important as probiotics. Both work in concert to modulate the immune response and set children up for a healthy immune system. Remember that infectious diseases used to kill a ton of kids. Even though we can usually take care of acute infections with modern medicine, it’s nice to be able to count on your immune system, too.
I suggest everyone punch their children’s meals into a food tracker for a week or so to get an idea of their nutrient intakes. Cronometer and MyFitnessPal are good.
Should You Manage Your Kid’s Macros?
Make sure they’re getting enough protein/fat/carbs?
Not really. I’m a fan of the “unfeeding” approach. Like the unschooler allows the child to make decisions about his education, providing only resources and guidance when requested, the unfeeder provides a meal with all three macronutrients represented and lets the child decide what and how much to eat.
If it’s obvious, and your kid’s eating sweet potato after sweet potato and totally ignoring the beef and broccoli on the plate, make some rules. But for the most part, kids eat as much as they need. This laissez faire approach to feeding kids, however, only seems to cause problems when they have unfettered or regular access to industrial foods and beverages like French fries, pizza, crispy snacks, soda, candy, and other food products designed to trigger the reward system and override natural satiety signaling. It tends to work well when you offer things like this:
Eggs (especially the yolks)
Bone marrow
Bone broth
Gelatinous meats (oxtail, cheek, shank, etc)
Organ meats
Fish eggs (ikura, or salted salmon roe, is a great option at sushi places or Japanese markets)
Fish (fresh, canned, bone-in)
Cheese
Yogurt/kefir
Raw milk
Berries
Starchy tubers
Colorful fruits and veggies
Beets
Seaweed
Coconut milk/butter
Legumes, properly prepared and tolerated
Bananas, slightly green for moderate resistant starch content
As a longtime parent, I’ve learned a few things. I’ve developed a few tricks. I’ve made some observations you may find illuminating. What follows are the tips, tricks, and rules I’ve found very useful in feeding kids well.
Don’t assume your kid is intolerant of everything.
Don’t ignore obvious intolerances or allergies. Just don’t seek them out when they don’t actually exist. Chances are, your kid can enjoy and benefit from full-fat dairy, white potatoes, nightshades, eggs, and even the occasional legume.
“Seven bites.”
7’s a good number, but it could be anything. Make a household rule that you have to take at least 7 bites before deeming a food “yucky.”
Calories count.
But not like you’re thinking. Overall calorie intake is very important for growing children. They’re like CrossFitting endurance athletes training for an MMA fight—they need to eat. Big things are happening constantly in their bodies, and they need plenty of food to support the changes. Don’t consciously limit (or let your kid limit) your kid’s calorie intake unless you have a valid medical reason.
Egg yolks disappear into everything.
Spaghetti sauce? Add a few egg yolks after you’ve turned off the heat.
Mac and cheese? A few egg yolks enrich it without changing the flavor.
Scrambled eggs? Add an extra egg yolk.
There’s nothing wrong with a smoothie.
There’s a lot right. A well-designed smoothie can provide tons of important nutrients. An example:
Baby kale (vitamin K, phytonutrients, magnesium, calcium, folate, potassium)
Frozen green banana (resistant starch, potassium)
Kefir (probiotics, fat, folate, vitamin k2)
Egg yolk (choline)
Whey protein
Brazil nut (selenium)
Cod liver oil (vitamin A, vitamin D, DHA/EPA)
Frozen mango (vitamin C, vitamin A, folate), coconut water (potassium, magnesium)
Kids will eat anything in popsicle form.
Take the leftovers of the nutrient-dense smoothies you make and freeze them in popsicle molds. There, that’s “dessert.”
Rice is an excellent vehicle for nutrition.
Rice is just empty carbs. Right? Not necessarily. Sub bone broth for water, add a dash of Trace Minerals, throw in a few shakes of kelp granules? Suddenly, your rice is a repository of magnesium, collagen, iodine, and other nutrients they may not be getting elsewhere.
Plus, kids are whirlwinds of energy. If they’re doing childhood right, they’re moving constantly. They can actually use those empty glucose molecules.
Crackers are good vehicles for nutrient-dense dips.
Sure, you don’t want your kid killing a box of rice crackers by themselves. As vehicles for things like tuna salad, liver paté, good cheese, hummus, however, they excel.
Fish sauce as a training tool for picky eaters.
Real fish sauce made from fermented salted fish is a potent source of glutamate, a flavor-enhancing amino acid that can teach picky eaters to like novel foods. It also makes food taste good on a subjective level, so you’ll be hitting them from two angles.
Frozen fruit is dessert.
If it’s cold and sweet, kids assume it’s a popsicle. Mangos, strawberries, blackberries, cherries. Forget ice cream for dessert. Serve up a big cup of frozen blueberries, perhaps with some real whipped cream. (This may work on adults, too)
Toothpicks make everything delicious.
If your ungrateful kid won’t eat your seared scallops, or your perfectly medium rare lamb chops, stick some toothpicks in. For whatever reason, kids just can’t resist toothpicked food.
Bribing works…in the short-term.
On a population level, at least. School children offered small prizes in the lunch line if they chose the “healthier” option were more likely to choose it. Be wary of relying on this. Negotiating with terrorists may work in individual instances, but it sets a bad precedent for future incidents.
Well, that’s it for today, folks. I hope you come away with a better grasp of children’s nutrition needs. Let me know how any of those strategies and rules work for you and your family. And please chime in down below with your own tips for feeding kids right. I know we’ve got a ton of parents out there.
Until next time be well
