Nutrition from Head to Toe During Puberty (Part 1)

This is Part 8 of my Puberty and Growth Series (Part 1 of 2 about Nutrition during puberty)

Remember when you put so much care and thought into your child’s first foods? After age two the crazy growth of infancy slows then it stabilizes during the school years. By age 10, early adolescence hits and the body goes through the second largest growth spurt. But this one is longer: 4-6 years!

Now instead of being in control of what your child eats, you have a kid with likes and dislikes making eating decisions in the real world. The same care that you put into your child’s eating needs to be revisited but in a different way.

So in two posts, we’ll be reviewing the unique needs of early adolescence from head to toe, followed by a third post about how to talk to children regarding the care and feeding of their growing body.

The Brain

The adolescent brain is like a house that is being remodeled. The foundation stays the same but improvements are made so all the pieces can work together more efficiently. This “brain remodel” occurs between the ages of 12 and 25. This remodel couldn’t occur without myelination, which increases processing speed, and the pruning of unused synapses. Two key nutrient players in this remodel are DHA and vitamin B12.

DHA continues to increase in the brain during adolescence to reach about 15% of fatty acids. This increase occurs during an important time: frontal cortex synaptic pruning, increased white matter, and overall brain maturation. Emerging research shows a link between DHA status and depression and other psychiatric disorders, behavior/attention and learning. According to one review in the journal Nutrients:

The brain’s frontal lobes are particularly responsive to the supply of DHA during development. Decades of work have clearly established the responsibilities of the frontal lobes for executive and higher-order cognitive activities including sustained attention, planning and problem solving, and the prefrontal lobe in particular for social, emotional and behavioral development. Therefore, maintaining optimal lipid composition in these brain regions, and specifically DHA levels, is not only important during the development and maturation of the brain from gestation through childhood and adolescence but such maintenance is also critical for successful aging of the adult brain.

Vitamin B12 is also needed for proper brain development. B12 is involved in myelination and the making of red blood cells. Vitamin B6 helps increase the absorption of B12.

Who’s at risk?

When it comes to DHA, everyone! That’s because of the weekly 8-10 ounces recommended of seafood, 9 to 13-year-olds only get an average of less than 3 ounces. Vitamin B12 is not a nutrient of concern unless the child doesn’t eat animal products (vegan).

Eyes

Adolescents need vitamin A for proper eye health. In particular, vitamin A helps ensure there is a barrier (mucous) between the eye and viruses, decreasing the risk of eye infections. It also aids night vision. Vitamin A not only plays an important role in vision, it helps the immune system and bones grow too.

Who’s at risk?

Because intake of red/orange and dark green veggies is well below recommended levels, so is vitamin A. About 15% of meals age 9-13 have intakes below the estimated average requirement and that jumps to 49% at age 14. Twenty-four percent of 9-13-year-old girls aren’t getting enough and that jumps to 53% at 14.

Blood Volume

When a restaurant gets an unexpected surge of customers you need enough food servers to meet this demand. You can think of the rapid tissue expansion in bone, muscle, and brain during puberty the same way. More blood volume, including red blood cells (RBCs), is needed to meet growth demands. RBCs contain hemoglobin, a protein that holds oxygen. Just like food servers carry out food to hungry customers, RBC’s carry oxygen to growing tissues. And because RBC’s live for only about four months they continually need to be renewed.

Three nutrients of particular importance to this process are iron, folic acid, and vitamin B12. To make enough hemoglobin the body needs adequate iron stores. Folic acid works closely with vitamin B12 in making red blood cells and ensuring iron is working properly. When RBCs cannot be produced in amounts that match the body’s need, anemia occurs. The most common type of anemia is iron deficiency anemia.

Who’s at risk?

Females are at higher risk than males, especially when there is blood loss from menstruation. About 9-16 percent of female adolescents are iron deficient while 2-5% are anemic. Vegetarians are also at increased risk for anemia. But all children growing through puberty need to be sure they are getting enough iron, folic acid, and B12.

The Heart

Adolescence is a good time to lay the foundation for heart-healthy habits as these behaviors tend to track into adulthood. Beneficial heart-healthy habits include a nutritious diet, physical activity, adequate sleep, and stress management. Also, it’s not just what kids do but the habits they don’t develop. For example, ninety percent of adult smokers started before they graduated high school. It’s important to still manage sweets and keep soda intake to occasional. And keeping the family meals coming so fast food doesn’t take over.

Two key nutrients involved in the heart are potassium and magnesium. Adequate potassium is important for muscle function and helps the walls of blood vessels relax, helping maintain a healthy blood pressure. The mineral magnesium also helps blood vessels relax, transports potassium and calcium, and regulates hundreds of other body systems.

Who is at risk?

Due to low fruit and vegetable intake, most adolescents get about half the recommended amount of potassium. Twenty-two percent of 9-13-year-old males get below the recommended average requirement for magnesium. That jumps to 75% at 14-18 year of age. For girls, those numbers are 36 to 87% respectively.

Part 2 Coming Up

Well, hat’s enough nutrition talk for now. In our next post, we’ll discuss muscle mass and body fat, bone, the GI tract, and skin. If you haven’t already, check out my other posts on child nutrition:

DHA for Kids: The Complete Guide for Parents

Vitamin D: What Parents Need to Know

2015 Guidelines: What Parents Need to Know

Don’t miss my book for girls which includes the research from this series plus so much more. My Body’s Superpower helps girls going through puberty grow up healthy, confident and strong (a book for boys coming next).