Chapter 15: Adolescent Nutrition: Conditions and Interventions

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Welcome back to The Deep Dive.

We're here to take complex research today.

It's all about adolescent nutrition, drawing heavily from a key textbook chapter and really break it down for you.

FAST, our mission today, to get a handle on the full picture for teenagers.

We're talking about the big issues like obesity, eating disorders, but also the specific needs of teen athletes and managing those early chronic disease risks.

Okay, let's unpack this.

We're aiming to go deeper than just definitions.

We want to look at how common these things are, the physiology behind them, the latest treatments, and some really important shifts in how we think about care.

Yeah, and that shift is so important because adolescent nutrition is not just about physical growth.

It's this whole continuum of behaviors we need to understand.

It really ranges from

typical growing pains, let's say, all the way to serious clinical stuff.

So anyone working with teens needs that specialized insight.

It's complex.

Definitely.

Let's jump right into maybe the biggest challenge right now.

Overweight and obesity in teens.

How do we even measure that accurately?

Right.

For adolescents, you absolutely have to use the BMI for age percentiles.

It's age and sex specific based on the CDC growth charts.

You can't just use adult BMI cutoffs.

Okay, so percentiles are key.

What are the categories then?

So overweight is defined as being between the 85th percentile up to but not including the 95th percentile for their age and sex.

And obesity.

Obesity is at or above the 95th percentile.

And then there's a category for extreme obesity.

Extreme obesity.

How's that defined?

That's for teens who are at 120 % of that 95th percentile mark or they have a BMI of 35 or more, whichever is lower actually.

The trends you see in the NHNES data looking from the 70s up to 2018, they're pretty shocking, aren't they?

Oh, absolutely alarming.

We've seen obesity rates nearly quadruple and severe obesity.

That's increased about sixfold among kids and teens aged two to 19 in the U .S.

Wow, sixfold.

And I read there was a difference between boys and girls in that severe category.

Yeah, that's an interesting detail.

The data showed that the increase in the highest weight categories, particularly severe obesity, was actually more dramatic for male teens.

It went up about sevenfold for them compared to about fivefold for female teens over that period.

So with numbers like that, how has the treatment approach changed?

It can't just be eat less, move more anymore, surely?

Exactly.

That's the big shift.

The thinking now is really treating obesity as a chronic disease like diabetes or high blood pressure.

It needs a chronic care model.

Which leads us to something called intensive health behavior and lifestyle treatment or IHBLT.

That sounds, well, intense.

What does it actually involve?

It is intense and it's team -based.

That's crucial.

You need a physician, a registered dietitian nutritionist, someone from behavioral health, maybe others too.

A whole team.

Yes.

And the guidelines are specific.

It requires 26 or more hours of contact time with the patient and family.

26 hours over what time frame?

Spread over three to 12 months.

And the counseling approach really matters too.

Motivational interviewing or MI is preferred.

Why MI specifically?

Because it's about working with the family, figuring out what they're ready and willing to change rather than just telling them what to do.

It respects their autonomy.

Okay, 26 hours team -based care.

That actually getting that kind of sustained support is tough in the real world.

Access must be an issue.

That's absolutely the challenge.

IHBLT is the gold standard, no question.

But yeah, resources, insurance, access.

It often means there's a gap between what we know works best and what families can actually get.

So if IHBLT isn't enough or maybe not accessible, what's next for the most severe cases?

Well, for adolescents with severe obesity, especially if they have significant health complications, we have to consider bariatric surgery.

Surgery for teenagers, what are the criteria for that?

It's not taken lightly.

Generally, they need to have a BMI over 35 and a serious related health problem like type 2 diabetes or severe sleep apnea.

Or a BMI of 40 or greater, even without those other issues.

And the outcomes.

I heard they can be pretty dramatic, especially for things like diabetes.

They can be remarkable.

There's data showing, for example, that three years after surgery, something like 95 % of teens saw their type 2 diabetes go into remission.

95 % remission, that's huge.

That could change a whole life trajectory.

But it's a major surgery with major life changes afterwards, right?

Absolutely.

It demands lifelong commitment to specific nutritional protocols.

You have to manage the altered digestion.

What does that look like day to day?

It means eating three or four very small meals, focusing on high protein foods first.

Like protein first at every meal.

And fluid intake is critical, aiming for two to three liters daily, but only non -sugar sweetened drinks.

And here's a key detail.

No drinking fluids for 30 minutes before or after eating.

Why that specific timing with fluids?

To prevent something called dumping syndrome is where food moves too quickly from the stomach into the small intestine, causing really unpleasant symptoms like nausea, cramping, diarrhea.

Avoiding fluids around meals helps manage that.

So if we connect this to the bigger picture,

the potential benefits like diabetes remission are massive, but they come with these really demanding lifelong adjustments and potential downsides.

Precisely.

High success rates, yes, but also significant risks and side effects.

For instance, nutrient deficiencies are common.

One study found over half, 57 % of teens experienced low iron stores, hypoferritinemia after surgery.

Low iron.

That makes sense with altered absorption.

It does.

Especially after procedures like the Roux -en -Y.

It just highlights why they need intensive lifelong nutrition monitoring and supplements.

That level of occurrence, the focus on food, it really brings up the other side of the coin, doesn't it?

The societal pressures around weight, dieting.

It does.

And that leads us right into that continuum.

Body dissatisfaction, dieting behaviors, disordered eating, and then clinical eating disorders.

And let's map that out.

It starts with just feeling unhappy with your body.

Often, yeah.

Body dissatisfaction.

That can then lead someone to start dieting.

Then maybe those behaviors become more extreme, more disordered.

And for some, it progresses to a full -blown clinically diagnosable eating disorder.

And that first step, dieting.

It's incredibly common, isn't it?

Especially among teenage girls.

Brighteningly common.

Data suggests over 60 % of adolescent girls and maybe 30 % of boys have reported dieting.

60%.

Yeah.

And we really need to see that as a major red flag.

It's not benign.

Dieting itself is a significant risk factor for developing both future obesity and eating disorders.

So it can backfire in two directions.

Okay.

When it does escalate to that clinical level, what are the main eating disorders we see in teens?

The three major ones are anorexia nervosa, bulimia nervosa, and binge eating disorder.

Let's take anorexia nervosa,

what defines that?

NN involves a refusal to maintain even a minimally normal body weight for their age and height.

There's an intense overwhelming fear of gaining weight and a really disordered perception of their body shape or size.

And it's incredibly dangerous.

Right.

Tragically so.

It has the highest mortality rate of any psychiatric condition, potentially up to 5%.

There are subtypes too, restricting type and binge eating purging type.

Okay.

Then bulimia nervosa, BN.

How is that different?

BN is characterized by recurrent episodes of binge eating, consuming a large amount of food in a short time, feeling out of control, followed by inappropriate compensatory behaviors to prevent weight gain.

Compensatory behaviors?

Like what?

Things like self -induced vomiting, misusing laxatives or diuretics, fasting, or exercising excessively.

For a diagnosis, this binge purge cycle has to happen at least once a week for three months.

And unlike AN, people with BN aren't always underweight.

Correct.

They might be underweight, normal weight, or overweight.

The core issue is that cycle of behavior and the distress it causes.

And the third one, binge eating disorder, BED.

BED involves those recurrent binge eating episodes.

Again, with that feeling of loss of control and significant distress afterwards, like eating very fast, eating until uncomfortably full, eating alone due to embarrassment.

But critically, it's without the regular use of those inappropriate compensatory behaviors seen in bulimia.

Okay.

So given how dangerous focusing too much on weight can be, potentially triggering these disorders, you mentioned a paradigm shift in care.

Yes, a really crucial one.

It's the move towards a weight inclusive approach.

You can find the principles laid out nicely in table 15 .3 in the source text.

Weight inclusive.

What does that mean in practice for a health care provider?

It fundamentally shifts the focus away from weight or BMI as the primary measure of health.

The core idea is accepting that bodies naturally come in a variety of sizes and shapes.

Health isn't defined by a number on the scale.

So instead of setting weight loss goals.

Exactly.

The focus turns entirely to promoting health enhancing behaviors.

Things like improving sleep, finding enjoyable ways to be physically active, developing a more peaceful relationship with food, managing stress, things everyone can benefit from regardless of their weight.

That sounds radically different from how weight is usually discussed in doctor's must be hard to implement.

It can be challenging.

Yeah.

It requires conscious effort and training, especially in using non -judgmental language.

How so?

Like if you have to report a BMI.

You state the number neutrally, just the facts.

You don't label it as good or bad.

You don't prescribe an ideal weight based on it.

This is so important because we know weight stigma is incredibly harmful.

Stigma, even from health care providers.

Sadly, yes.

Patients report experiencing weight bias in health care settings.

Research shows this stigma actually increases the risk for poor health outcomes.

Things like hypertension, depression,

and ironically even more binge eating.

Wow.

Okay.

Let's pivot now to a group with really different nutritional needs.

The adolescent athlete.

You mentioned over half of U .S.

teens play organized sports.

Yeah, about 57%.

And that participation ramps up their energy and nutrient needs significantly.

How much more energy are we talking?

It varies a lot.

It depends on the sport, the intensity, growth, sports.

But it could easily be an extra 500 to 1500 calories per day compared to their non -athlete peers.

And if they don't get those extra calories and nutrients?

That's when you run into problems.

Specific micronutrients become big concerns.

Like which ones?

Calcium is a big one.

Teens are still building peak bone mass and athletes put extra stress on their skeletons.

Low calcium intake, especially common in female athletes, increases fracture risk.

Big sense.

What else?

Iron.

Iron deficiency anemia is a real risk.

Athletes lose more iron through sweat and sometimes tiny amounts of gut bleeding from intense activity.

Plus, they're growing fast.

And for female athletes, heavy periods add another significant iron drain.

And anemia isn't just feeling tired, right?

For an athlete, it must really hit performance.

Absolutely.

Iron is essential for carrying oxygen to muscles.

Anemia directly limits their endurance, their power, their recovery.

It's a fundamental performance limiter.

Okay.

Beyond calories and micronutrients, hydration must be critical too, especially for younger athletes.

Huge.

Younger teens, especially those who haven't gone through puberty fully, are actually more vulnerable to heat illness.

Their bodies aren't quite as efficient at regulating temperature yet.

So are there specific guidelines for how much they should drink?

Yes.

Very specific.

Table 15 .1 in the text lays it out clearly.

Before activity, about one, two hours prior, they need 12 to 22 ounces of cool water.

Okay.

12 to 22 ounces before.

What about during?

During exercise, the recommendation is four to six ounces of cool water every 15 to 20 minutes.

Consistent small sips.

And after they're done?

They need to rehydrate based on weight lost.

The guideline is two to three cups.

That's 16 to 24 ounces of cool fluid for every pound of body weight they lost during the activity.

Wow.

That's quite precise.

Needs planning.

What about food?

What should they eat before a game or competition?

Is there an ideal pre -event meal?

Yes.

And the timing and what's in the meal really matter.

Table 15 .10 covers this.

The key takeaway is for meals eaten, say, four hours or more before exercise, they need to avoid foods high in fat, protein, and fiber.

Avoid fat, protein, and fiber.

Why is that?

Because those nutrients slow down how quickly the stomach empties.

You don't want food sitting heavy in the stomach during competition.

It can cause discomfort, cramps.

Plus, it delays getting carbohydrates digested and ready for energy use.

So complex carbs are the goal pre -event?

Primarily, yes.

You want to maximize the readily available energy from carbohydrates.

I know a lot of teens are focused on protein for muscle building.

Should they load up on protein right before they compete?

Definitely not right before.

High protein right before exercise is actually discouraged.

For one, it takes the place of those needed carbs.

Breaking down protein requires extra water for the body to get rid of the nitrogen waste.

Ah, so it increases dehydration risk.

Exactly.

Not what you want during intense activity.

Carbohydrate loading is a different strategy altogether.

That's more for endurance athletes.

Involves manipulating diet and training for days leading up to an event to max out muscle glycogen stores.

But that's quite specific.

Let's move into our final area, looking at chronic conditions that can start showing up in adolescence.

Things like high cholesterol, high blood pressure.

Right.

For hyperlipidemia or high cholesterol, screening can be a bit tricky.

Why is that?

Because cholesterol levels often dip naturally, maybe 10, 20 percent, during puberty due to all the hormonal changes.

So when is the best time to screen?

The text suggests two optimal windows.

Either around age 10 before puberty really kicks in, or wait until after age 17 when growth is mostly finished.

That makes sense.

What about hypertension, high blood pressure?

How is that defined in teens?

It's based on the average of three separate blood pressure readings, compared to percentile charts for age, sex, and height.

Pre -hypertension is readings between the 90th and 95th percentile, or if they're consistently over 2080.

And actual hypertension.

Stage one and stage two hypertension are classified based on readings consistently above the 95th percentile.

There are specific thresholds laid out in table 15 .14.

And if a teen has high blood pressure, what's the recommended approach?

Is it medication right away?

Usually lifestyle changes first.

The main dietary approach recommended is the Child One diet.

It actually incorporates principles from the well -known DASH eating plan.

DASH dietary approach is to stop hypertension.

What are the key parts of that Child One DASH approach for teens?

It puts a big emphasis on fiber, aiming for about 14 grams per 1 ,000 calories.

It also strictly limits fruit juice, only four to six ounces a day max, to control sugar intake.

And of course, reducing sodium according to age -appropriate guidelines.

Okay, and what about metabolic issues like diabetes?

We hear so much about type 2 rising in younger people.

It's a huge concern.

Pre -diabetes is estimated to affect maybe one in five adolescents now.

One in five!

Yeah, and that pre -diabetes stage is already linked with higher LDL, cholesterol, and blood pressure.

The actual incidence of type 2 diabetes is climbing too, particularly among certain groups, like non -Hispanic black teenagers.

It really flags the need for targeted prevention and early intervention.

We've touched on iron deficiency a couple of times.

Before we wrap up, are there other factors that impact nutrition, like substance use?

Definitely.

Using tobacco, alcohol, or illicit drugs can seriously mess with nutritional status.

How so?

Well, it often suppresses appetite, so teens might just not eat enough nutritious food.

But substance use also puts metabolic stress on the body, which can deplete stores of certain nutrients faster.

Specifically, thiamine, vitamin C, and again, iron stores can get depleted.

So iron keeps coming up.

We've got rapid growth, dieting, sports, menstruation for girls, substance use, all potentially impacting iron.

Exactly.

And what's fascinating here is how all these seemingly different things, intense athletics, heavy periods, maybe poor diet choices,

all converge on increasing the risk for the single most common nutritional deficiency in this age group,

iron deficiency anemia.

It really underscores the need for screening, doesn't it?

Absolutely.

That's why the recommendation is for all adolescent females to be screened for iron deficiency every five years, maybe even annually if they're elite athletes or have other known risk factors like heavy bleeding or restrictive diets.

Okay, that feels like a really comprehensive tour through the major nutritional challenges and considerations for adolescents.

A packed deep dive.

Yeah, we covered a lot of ground.

To recap quickly, we looked at the seriousness of adolescent obesity and the shift to treating it as a chronic condition, the vital importance of the weight -inclusive approach when dealing with eating disorders, the very specific energy, nutrient, and hydration needs of teen athletes.

And finally, those key screening times and dietary strategies for emerging chronic conditions like high cholesterol and hypertension.

And that complexity really highlights the need for an integrated team -based approach, doesn't it?

Especially for something like eating disorders, which disturbingly saw a massive spike during the COVID pandemic.

Some studies suggest incidents increase by up to 60%.

It really does demand collaboration.

So here's a final thought for you, our listener, to chew on.

We know that overly aggressive anti -obesity messages and the weight stigma that exists in society can both paradoxically increase the risk of kids developing eating disorders.

So the question is, how can public health campaigns and policies promote genuinely healthy behaviors, good nutrition, enjoyable movement without contributing to body dissatisfaction and causing unintended harm?

Something to think about.

Thanks for diving depth with us today.