A new study by my colleagues at Kaiser Permanente in southern California found that compared to youths in the medium range of average weight, youths at the high end of average weight had a 26 percent higher chance of developing hypertension within five years.
More Kids Could Develop High Blood Pressure
We have long known that children who are considered overweight are at increased risk of developing hypertension, also known as high blood pressure. But this study sheds light on the fact that even children who are at the upper end of average in terms of body mass index (BMI) (but not overweight) also are at increased risk of developing hypertension and all of the health conditions that accompany this condition.
As a pediatrician, I find this research extremely important: It motivates me to continue to work with my patients and their families on developing healthy lifestyles, including nutritious eating and regular physical activity.
Kaiser Permanente Study on BMI and Hypertension
The Kaiser Permanente researchers analyzed the electronic health records of more than 800,000 youths ages 3-17 between 2008 and 2015. The researchers compared youths by their initial body mass index with their change in BMI during a five-year follow-up. Researchers segmented average body weight into different ranges, including:
- Low: 5th-39th percentile
- Medium: 40th-59th percentile
- High 60th-84th percentile
Researchers also looked at the children’s blood pressure levels.
Among the key findings:
- Compared to youths in the medium range of average weight, the risk of developing hypertension within five years was 26 percent higher for youths at the high end of the average weight range.
- Every BMI unit gained per year increased their risk of hypertension by 4 percent.
- The rate of hypertension was higher among boys than girls.
While high blood pressure among children is relatively uncommon, the U.S. Centers for Disease Control and Prevention states that about 1 in 25 adolescents between ages 12 and 19 have hypertension. The CDC goes on to note that youth with cardiovascular risk factors, including high blood pressure, diabetes and obesity, are more likely to have these risk factors as adults, putting them at risk for heart disease and stroke.
“Hypertension during youth tracks into adulthood and is associated with cardiac and vascular target organ damage, such as thickening of the arteries, increased arterial stiffness and decreased endothelial function,” the Kaiser Permanente researchers noted. “With increasing evidence that the target organ damage might become irreversible independent of blood pressure control, preventing sustained hypertension and associated target organ damage in children is essential.”
And even children with persistent high blood pressure can develop health problems during childhood, including problems with the kidneys, brain and eyes.
Parents often ask me what normal blood pressure, height, weight and body mass index numbers are for kids. While absolute numbers are important, I recommend focusing less on the individual numbers and more on how their children are progressing over time. For example, if a child consistently stays on his or her growth curve, I am usually less concerned than if the child jumped three curves in a year. A jump that significantly corresponds with significant weight gain, and we would need to explore why that happened.
In addition to paying attention to growth curves, I encourage parents to focus on their children’s habits. What does your child drink every day? Are they getting too many calories from sugary juices and sodas? Are they drinking whole milk when reduced-fat milk is more appropriate? (Most children don’t need whole milk after age 2.) Are they snacking in front of the TV or eating chips while scrolling social media? Are they getting outside to play?
What Parents Can Do
When working with children to develop healthy habits, I encourage parents to get buy-in from their children. Our goal is for kids to learn to eat well and be active – and develop behaviors that stick with them for the rest of their lives. As a parent, try to figure out what makes your child tick, and use that as leverage to help them achieve healthy habits. A few ideas:
Involve children in meal preparation. That might mean asking your 3-year-old to help wash vegetables, your school-aged child to cut up vegetables, or your teenager to participate in meal planning and related grocery shopping.
Eat together as a family.
If your child has very specific food preferences and is only offered those food preferences, they forget how to explore other food choices. But if they see family members eating other foods, even if they aren’t ready to try a new food today, they are gaining familiarity and exposure so that at a future meal, they may be willing to take a taste. Eating together also helps your children improve their social and emotional skills. Talking together as a family about school and work is a wonderful way to bond.
Be active together.
As summer approaches, go outside and get fresh air. Fresh air is so beneficial for mental and physical health. Go for a hike, ride bikes, swim or simply go for a walk. Not only are you having fun together and connecting, but children also are learning how to have a healthy lifestyle and to reap the benefits of physical activity.
Don’t focus on the numbers.
Try not to worry about every pound your child gains or even loses. Instead, look at overall patterns and remember that weight fluctuates. It’s the big weight changes that are more concerning and warrants a conversation with your child’s pediatrician.
The Kaiser Permanente study points out that the rate of hypertension was higher among youth on state-subsidized health plans. Some families simply don’t have as much access to healthy food and activities as other families. If your child has a classmate who may have limited access to healthy food, consider inviting the child over for a healthy dinner or an outing to the park. If you have challenges accessing healthy food choices – please talk to your pediatrician to find out about resources that may be available.
If you have any concerns about your child’s weight, height, BMI or blood pressure, reach out to your pediatrician, who can help allay your worries and work with you and your child to address potential problems. Bringing up concerns is the best way to ensure early treatment, if needed, for any health problems, including overweight and obesity.