Processed Foods, Screen Time, and Childhood Obesity: What Parents Need to Know | Renee Paro, MD
Raising Heart-Healthy Kids in a Screen-Filled, Snack-Filled World
When my friend and colleague, pediatric cardiologist Dr. Renee Rodriguez Paro, finished her training at Stanford, she imagined herself in the cath lab doing high-intensity interventions on the tiniest of hearts.
Then she had her son, Micah.
She started fellowship with a six-month-old baby at home and found herself asking a question so many physician moms quietly wrestle with.
“Do I still want this exact version of my career?”
She loved cardiology. She loved her patients. But the idea of long nights in the hospital, getting called in at 2 a.m. for emergency procedures, no longer matched the kind of mother and doctor she wanted to be.
So she did something brave. She stepped off the conveyor belt of academic medicine, said no to the expected path, and chose outpatient pediatric cardiology with a focus on prevention. Not just saving children with complex heart disease, but helping everyday kids keep their hearts healthy from the beginning.
That choice, plus a box of sugary cereal from her son’s backpack, eventually led to her nonprofit, Dr Vegetable, and a powerful message for families trying to raise healthy kids in a world of screens, ultra-processed foods, and intense youth sports.
This article brings together what Renee teaches her patients every day about children’s heart health, cholesterol, nutrition, movement, stress, and how to balance real life with prevention.
What Pediatric Preventive Cardiology Really Looks Like
Most people hear “pediatric cardiologist” and picture ICUs, open heart surgery, and complex congenital heart disease. That is an important part of the field, and it is how Renee trained.
But her day-to-day outpatient work looks very different. She sees:
Kids with chest pain that is usually not from their heart.
“Innocent” heart murmurs that sound scary but are actually benign.
Fainting episodes that need to be sorted out.
Children and teens with high cholesterol, elevated blood sugar, high blood pressure, or higher BMI.
Her specialty within cardiology is prevention. She sits with families whose children have abnormal lipid panels or other metabolic risk factors. She explains what those numbers mean, where genetics fit in, and how daily choices affect the heart over time.
Renee believes, very strongly, that true prevention starts in childhood. Adult preventive cardiology is important, but by the time someone is in their 40s or 50s, disease has often been silently building for decades.
In kids, she has a chance to change the trajectory early.
Understanding Cholesterol, Blood Sugar, and Blood Pressure in Kid Language
One of the most practical things Renee does is explain basic physiology in a way kids can actually understand.
When a child walks into her prevention clinic with high cholesterol or high blood pressure, she does not start with “You need to eat better and exercise.”
She starts with, “What is cholesterol?”
She gets all kinds of answers. Then she explains, in simple terms:
Cholesterol is a little particle that travels in your blood.
Certain kinds of cholesterol can get into the walls of blood vessels and form plaque.
Those plaques narrow the “highways” that carry blood to your organs.
She compares:
Blood vessels to highways.
Blood to delivery trucks carrying oxygen and nutrients.
Atherosclerosis (plaque buildup) to traffic jams that block those trucks.
If those highways get clogged enough in adulthood, the heart muscle does not get enough blood and oxygen. That is when people have heart attacks.
She also talks about blood sugar:
Sugar itself is not literally “sticking to the blood vessels” the way people often picture.
But consistently high blood sugar makes blood vessels unhealthy and more vulnerable to damage.
And she breaks down blood pressure:
Higher pressure makes the heart work harder as a pump.
Over time, that pressure can damage vessel walls and contribute to long-term disease.
Importantly, she tells kids that these serious problems do not develop overnight, and they are not happening in their hearts right now. That is why she wants to talk about them early, while there is time to prevent them.
Why All Kids Now Get Cholesterol Screening
In 2012, the American Academy of Pediatrics updated their guidelines to recommend universal lipid screening for all children between ages 9 and 11.
Before that, only kids with obvious risk factors were supposed to get checked, such as:
A strong family history of heart disease.
Obesity.
High blood sugar or other metabolic problems.
But pediatricians noticed a big problem. Many families did not know their true family history, or kids with risk factors were still slipping through the cracks. Meanwhile, cardiovascular disease became the number one killer of men and women.
So the recommendation shifted to: check everyone.
That is how many of Renee’s prevention patients find their way to her clinic. Their pediatrician orders routine labs at ages 9 to 11. The results come back, and the cholesterol is high.
Some of those kids have clearly modifiable lifestyle factors. Many are eating a lot of processed foods and not moving much.
But a surprising number of Renee’s patients eat relatively healthfully and still have high cholesterol. That is where genetics comes in.
Genetics, Cholesterol, and Letting Go of Shame
Renee has been practicing almost a decade, and she has seen a pattern.
More and more of the high cholesterol she sees in kids is driven by genetics.
She spends a lot of time normalizing this with families, because cholesterol carries a kind of moral judgment in our culture.
Parents often arrive feeling ashamed and guilty, assuming a high number means they have failed their child. Kids feel like something is “wrong” with them.
Renee re-frames it:
There is almost always room for improvement in anyone’s diet, including her own.
But high cholesterol is often not a sign of laziness or “bad” behavior.
Genetics play a real and powerful role.
She does prescribe statins for some pediatric patients with significantly high cholesterol, especially when genetic factors are clearly involved.
And she is very clear about a few things:
Medications are reserved for select children after careful discussion.
Lifestyle change is always addressed first.
Even when a child starts a statin, nutrition and movement remain essential.
She also knows this topic can trigger strong reactions about “Big Pharma” or “overmedicating kids.” She meets that with calm clarity. Some children truly benefit from medication as part of a thoughtful, stepwise approach. It is not a quick fix, and it is never the whole story.
How She Talks to Kids About Food Without Talking About Weight
The nutrition conversation is where things get delicate.
Renee cares deeply about metabolic health. She also knows that talking about weight with children can easily tip into shame, disordered eating, and a damaged relationship with food.
So in her prevention clinic, she rarely talks about weight at all.
Instead, she anchors the conversation in:
Cholesterol numbers.
Blood sugar levels.
Blood pressure.
She explains why those numbers matter and how food affects them. Then she takes a detailed dietary history, meal by meal and snack by snack.
She tells families very clearly:
“This is not about judgment. I do not care what you eat so I can criticize it. I care so I can help you.”
From there, she gives targeted, realistic suggestions based on their actual lives, not a perfect textbook plan.
The Power of Fiber, Fruits, and Vegetables
If there is one recurring theme in Renee’s counseling, it is fiber.
She talks constantly about the power of fruits and vegetables. Not fancy superfoods. Not only organic or from a specific farm.
She spends a surprising amount of time debunking myths about fruit.
Many parents worry that fruit “causes diabetes.” She is blunt: no one is developing diabetes because they ate too many apples or oranges. The concern is added sugars in processed foods, sugary drinks, and sweets, not whole fruit.
Her nonprofit, Dr Vegetable, was born out of this passion.
From Box Tops to “Dr Vegetable”
The turning point came when Micah came home from elementary school excited about collecting General Mills Box Tops to raise money for the school.
Renee took one look and felt furious.
She was spending her days helping kids understand the dangers of ultra-processed foods, then watching large food companies market sugary cereals and snacks as “helping schools” through box top programs.
At the same time, in her clinic she was joking with families that she should change her name to “Dr Vegetable,” because she talked so much about produce.
Her husband, John, a plastic and reconstructive surgeon and talented musician, suggested turning that frustration into action.
They created a program called “Shop Crops, Not Box Tops.”
Here is what they did at their elementary school:
Renee, as “Dr Vegetable” in her white coat, taught kindergarteners about heart health and the benefits of fruits and vegetables, in fun, simple language.
John put on a vegetable costume and sang silly songs about peas and poop and how fiber helps the body.
Kids were given a sheet to track fruits and vegetables they ate, and for every completed sheet, they donated money to the school.
The response from parents was incredible.
Children who had ignored vegetables for years were suddenly asking what was in the bowl on the counter and insisting they needed that food “for my cholesterol” because of Dr Vegetable.
The program expanded to the whole school, and eventually they made Dr Vegetable a 501(c)(3) nonprofit. COVID slowed them down, but they revived it with the older grades and started a run club where every adult volunteer wears a vegetable costume while teaching kids about how running helps the heart.
It is silly, joyful, and incredibly effective. Kids remember it. They change their behavior because of it.
Screens, Stress, and Sedentary Kids
Of course, food is only one piece of children’s heart health today. The other big piece is movement, stress, and screens.
Renee does not pretend screens are going away. She is honest with her patients.
Her own kids play video games.
Her kids watch iPads on Friday nights so she and her husband can spend time together.
Many kids socialize through games like Roblox the way previous generations did on bikes or in the backyard.
Instead of demonizing screens, she teaches kids to understand how screens fit into their overall health.
In clinic she asks:
“What do you do to move your body?”
“What do you do when you feel stressed?”
“How much sleep are you getting?”
“What kind of games do you play?”
She talks about the four pillars she looks at:
Movement.
Nutrition.
Stress and coping.
Sleep.
She explains that:
Screens can feel relaxing in the moment, but they rarely truly reduce stress.
Exercise, creative activities, and real-life connection are much more effective at calming the nervous system.
One of her favorite questions is, “What did you love to play with when you were younger?”
Legos. Drawing. Barbies. Building things.
Then she asks, “Why did you stop?”
She gently encourages teens to bring play back into their lives. Adults have almost no play, she reminds them, and it is hurting us. They do not have to rush into that same pattern.
For kids who struggle to stop gaming, she recommends setting a timer themselves. When it goes off at an hour, they will not feel like stopping. They will want to say “one more game.” But learning to stop anyway is part of managing their life and making room for other things their heart and body need.
Stress, Sleep, and the “Why” Behind Cravings
Renee does not look at food in isolation.
She ties together:
Chronic poor sleep.
Daytime fatigue.
Reaching for salty or sugary snacks at midday.
Test anxiety and “stress eating.”
If a teen is exhausted because they are up late on their phone or studying, of course they will crave quick energy at noon. Of course it is hard to choose carrots over chips in that moment.
Instead of scolding, she connects the dots so kids understand their body’s logic, then offers realistic changes:
Improve sleep first.
Build in short, enjoyable movement daily.
Add fiber and protein so they are not constantly crashing.
Again, the tone is nonjudgmental. The goal is understanding and practical tweaks, not perfection.
When Athletes’ Hearts Struggle
On the other end of the spectrum, Renee sees a lot of young athletes.
They are not worried about obesity or sedentary living. They are worried they cannot perform the way they used to.
Common story:
As a sophomore, they could run a certain pace or train for hours.
Now, despite intense training, they feel slower, more tired, or weaker.
They worry something is wrong with their heart.
Renee evaluates them medically, of course. But often what she finds is not a heart defect. It is overtraining and under-recovery.
Patterns she sees:
Every training session is at 100 percent intensity.
They are in multiple AP classes plus 2 hours of sports practice daily.
They are not eating enough carbohydrates because they have absorbed messages that carbs are “bad.”
They are sleeping too little and never truly resting.
As an endurance athlete herself who has run many marathons, she has credibility when she says:
You need true rest days.
You need easy days where you still move but not at full effort.
You need enough carbohydrates to support athletic performance.
She also knows that many coaches are getting better about this, but not all. Some still push kids in ways that lead to injury and burnout.
She and I both see what happens when kids specialize in one sport too early, or play the same sport on multiple teams without downtime. The body can only withstand that level of intensity for so long before something gives.
What Renee Has Learned From Her Own Training
Renee grew up playing multiple sports: softball, basketball, golf, tennis, bowling. Like many of us, she stopped regular exercise during training because she felt she “had to just study.”
During residency and fellowship, she hit a deep period of burnout.
Re-prioritizing exercise changed everything for her mental health. It became her anchor.
She ran her first marathon the year she finished medical school in 4 hours and 5 minutes and intended for it to be a one-time accomplishment.
Nine years and two kids later, she ran the Chicago Marathon in 3 hours and 17 minutes. She was hooked.
Since then, she has done many marathons and become deeply immersed in the running community. She describes marathon day as “the best of humanity,” where every runner has a story and every volunteer and spectator is there to support someone doing something hard.
Along the way, she learned some critical lessons that apply directly to the teens she counsels:
Cardio alone is not enough. Strength training is essential to prevent injury.
In her 40s, she cannot rely only on running and expect her body to tolerate multiple marathons a year.
She now builds dedicated strength-only phases into her year to maintain and build muscle.
She also discovered that her natural tendency to “go hard” all the time was working against her.
Through detailed testing with a performance-focused company, she learned:
Her body is very good at high-intensity efforts and tolerating high lactate.
Her lower-intensity capacity, the true aerobic base, was underdeveloped.
So she committed to training with more discipline, especially around heart-rate zones.
Keeping her heart rate in Zone 2 for easy runs has been surprisingly difficult. She feels fine pushing harder, but she knows that if she wants to run “forever,” she needs to respect those lower zones and build a stronger aerobic foundation.
She shares this openly with young athletes: if you want a long career in your sport and a long health span, you cannot live at maximum intensity. You have to think about what your body will need when you are 60 or 80, and start acting accordingly now.
How Parents Can Support Heart-Healthy Kids Today
Pulling all of Renee’s wisdom together, here are the key takeaways for parents:
1. Know that prevention starts early.
Ask your pediatrician about lipid screening between ages 9 and 11.
If labs come back abnormal, do not panic. See it as information and an opportunity.
2. Focus on metabolic health, not weight.
Talk with your child about blood pressure, cholesterol, and blood sugar instead of numbers on a scale.
Avoid shaming language around food or body size.
3. Make fruits, vegetables, and fiber everyday staples.
Use whatever form is affordable and available: frozen, canned, or fresh.
Do not fear fruit. Whole fruit is not the enemy.
4. Look at the whole day, not just the plate.
How much sleep is your child getting?
Are they moving their body daily in ways they enjoy?
How do they cope with stress?
5. Be realistic about screens.
Acknowledge that video games and social apps are part of their world.
Help them set their own limits, like a one-hour timer they commit to honoring.
Encourage real-world play and creativity alongside their screen time.
6. If your child is an athlete, protect their long game.
Watch for signs of overtraining and burnout.
Make sure they are eating enough, especially carbohydrates, to fuel their sport.
Build in real rest days and easier training days.
7. Use your care team.
Cardiologists can explain heart and vessel health in kid-friendly ways.
Dietitians are fantastic for detailed meal planning and portion guidance.
You do not have to carry all of this alone.
Looking Ahead: A Future Built on “Dr Vegetable”
Renee is currently the department chair of pediatric cardiology and pulmonology, a mother, a marathon runner, and the co-founder of Dr Vegetable.
She loves her clinical work, but she is also honest that she may not be in the exam room forever. At some point, she expects to step out of day-to-day clinic to be more flexible for her family.
When that time comes, she sees Dr Vegetable as her next chapter: taking the message of heart health, nutrition, movement, sleep, stress, and play into more schools and communities.
Her rallying cry is simple and memorable:
“Shop crops, not Box Tops.”
As parents, we cannot control everything about the world our kids are growing up in. There will always be screens. There will always be processed snacks. There will always be pressure to perform, whether in school or sports.
What we can do is what Renee does with every family she sees:
Remove shame.
Explain what is happening inside their body in simple terms.
Celebrate small, realistic changes.
Keep the focus on long-term heart health and a life they can enjoy fully.
Healthy hearts start with tiny, daily choices. And it is never too early, or too late, to begin.