The changes tweens and teens go through can directly affect the way they eat or relate to food. A little parental guidance can help. (iStockPhoto)

Most parents expect their role to change as their kids hit their teen years. But many don’t realize quite how much their children’s age affects the way they need to be fed.

Countless wonderful transformations occur inside the bodies of tweens and teens, and many directly affect the way they eat or relate to food. After infancy, adolescence is the second most critical time for nutritious eating. So some rethinking is in order.

What’s changing?

●Hormone surges can make them moody, trigger sugar cravings and cause skin breakouts.

●During major growth spurts, kids have increased caloric requirements and may seem insatiable.

●Sports, extracurricular activities and homework schedules make it harder for them to sit down for a regularly scheduled family meal.

●Sleep patterns change; if kids wake up later, they may not be hungry for breakfast before school.

●Teens and tweens spend more time away from home, which means they eat more of their meals and snacks with peers.

●Kids this age are — appropriately — in the process of separating from their parents. Some may wage food wars: complaining about foods they used to eat happily, demanding junk food just to be contrary or adopting a specific diet (Paleo, vegetarian) that’s different from the rest of the family’s.

Absolutely all of this is happening in our house, along with the fact that my boys watch a lot of sports and are unquestionably lured by the sports drinks, protein powders and muscle-building products advertised. My smoothies and homemade granola bars no longer cut it.

These adolescent changes are normal, yet this doesn’t mean we parents should abandon our noble intentions to feed our kids well.

Guidelines for parents

●Continue to limit sugar at home; chances are they are getting enough elsewhere.

●Keep healthful food accessible so they can grab it on the go.

●Conversely, don’t label some foods as “bad”; it can cause teens to feel guilty or bad about themselves when they eat them. This becomes amplified as a teen’s self-esteem wavers and he or she feels pressured to have a certain body shape.

●Prioritize the family dinner.

●Remember that food, especially unhealthful food, shouldn’t be used as a reward for good grades, a sports championship or any other win. And on the flip side, food — or denial of it — should not be used as a punishment.

●Do not engage in battles over meals. Remove the emotion and stick to simple family rules of sitting down to dinner, using good manners and eating a little bit of everything.

Talking points

Remind your children why it is important to make healthful choices. Teens are old enough to understand the science behind why certain foods cause breakouts and plummet moods while other foods build muscle and energize. These are conversations you can have:

Do you want to keep your skin clear?

Our skin is our largest organ and excretes pounds of toxins and wastes every day. What we eat can show up on our faces.

Foods that support healthy skin include lots of water, blueberries and tomatoes for antioxidants, orange and yellow vegetables for Vitamin A, salmon and flax seeds for Omega 3 fatty acids, pumpkin seeds for zinc, and fermented foods for healthy digestion.

On the other hand, sugar, trans fats and allergenic foods such as gluten and dairy have all been shown to trigger skin inflammation, irritation and acne.

Help your body produce more of the chemicals that make you feel happy instead of those that make you feel low.

The foods we eat build the neurotransmitters in our brain that contribute to the feelings of happiness, joy and calm. Eating consistent amounts of protein throughout the day — eggs, fish, lean meats, beans, nuts and seeds — can really help maintain stable moods, as can consuming enough Omega-3 fatty acids.

And sugar, caffeine, artificial sweeteners, food coloring and additives have been shown to dampen mood.

Athletes need stamina. The right foods can help.

Eat a real meal after school and before sports practice instead of a bunch of high-sugar, low-nutrient snacks. Athletes will perform better with the nutrition from two dinners than they will from a backpack’s worth of processed grub.

Avoid sports drinks as many offer no nutrition and are filled with sugar, food colorings and added chemicals. And don’t bother with processed, chemical-laden protein shakes. Instead, blend a banana, a spoonful of nut butter, ground flax seeds, raw oats, coconut milk and frozen berries.

Girls, a lot is happening to you. Trust that it’s normal.

According to “The Teenage Body Book” by Kathy McCoy and Charles Wibbelsman, girls can go from an average of 8 percent body fat to 21 percent body fat during puberty. This does not mean you are fat; women need some fat in order to reproduce.

Rising estrogen sometimes causes girls to crave sweets. Try energizing alternatives to sugary snacks such as homemade trail mix, smoothies made with almond milk and frozen fruit, or a yogurt parfait.

There are some changes around puberty that aren’t apparent but are still important. The onset of menstruation changes a girl’s iron needs; in fact, the recommended daily allowance for girls ages 9-13 (8 mg/day) almost doubles to 15 mg/day for girls ages 14-18. Iron is found in beans, fish, eggs and red meat (grass-fed meat providing more important nutrients than grain-fed). Furthermore, hormone development relies on certain nutrients such as protein and healthful fats found in salmon, walnuts, flax seeds and avocados.

Want to do better in school? Eat breakfast.

Study after study has shown: Children who eat breakfast show improved academic performance, longer attention spans, greater attendance and decreased hyperactivity in school. They get better test scores. They eat less junk food. And they are less tired, irritable and restless during the school day. So eat breakfast.

You are constantly hungry because you are growing. That’s okay.

Just be smart about what you eat.

Eat an extra real meal instead of a lot of snacks: a bowl of beans and leftover rice or last night’s dinner. Make a smoothie, or a sandwich on whole grain or sourdough bread. Fry or scramble eggs with whole grain or sourdough toast. Snack on hummus, crackers, guacamole, organic chips and veggies.

Seidenberg is co-founder of Nourish Schools, a D.C.-based nutrition education company, and co-author of “The Super Food Cards,” a collection of healthful recipes and advice.