A diagnosis of high blood pressure, or hypertension, is often associated with old age. However, new guidelines from the American Association of Pediatrics, released in September 2017, mean there will likely be more children found to have high blood pressure during their annual physical exams. And that can have an impact on their bodies.

Because high blood pressure doesn't often show symptoms, it typically goes undetected. In fact, NBC News notes the condition goes unnoticed about 75 percent of the time.

But the new guidelines, which were created after analyzing about 15,000 hypertension-related articles, will help doctors spot more cases. NBC notes it was previously estimated that 1 to 2 percent of youths had hypertension. Now, with the use of the new guidelines, that identified rate has gone up to 3.5 percent.

Could your child's health be at risk?

Effects of High Blood Pressure

According to the American Heart Association, a healthy blood pressure reading is less than 120/80. Readings in the 120/80 to 139/89 range are regarded as prehypertension, which means you can still work on prevention through immediate lifestyle changes. Any blood pressure reading higher than 139/89 indicates high blood pressure.

It's important to know your child's numbers. It's also vital to understand what they mean for your child's health, now and in the future.

High blood pressure does more than just make you dizzy or sweaty. It's often touted as the "silent killer" because of its tendency toward having no symptoms before leading to a serious health event. The American Heart Association notes the negative effects high blood pressure can have on a person's heart health and body, including:

• Heart attack
• Heart failure
• Vision loss
• Kidney disease
• Stroke

Setting your child on a healthy path early in life can help them avoid cardiovascular disease and other issues as an adult.

Is Your Child at Risk?

The only way to really know for certain whether your child has high blood pressure is through a screening with their doctor. While anyone can be diagnosed with high blood pressure regardless of age, weight, race and other factors, certain influences do put your child at risk, according to the American Heart Association.

Consider your family history. If anyone in your immediate family has been diagnosed with high blood pressure, it's more likely your child will be, too.

Gender and age also can play a role. Before 45, men are more likely than women to live with hypertension. But men aren't overall more likely to experience hypertension — the likelihood becomes similar between genders from 45 to 65. After 65, females are more likely to become hypertensive.

Race can affect your child's chances, too. African-Americans are more likely to face hypertension than any other race, and at younger ages, as well.

Preventing High Blood Pressure

While these factors may be out of your control, certain lifestyle choices can affect your child's risk of hypertension.

A diet high in sodium and a lack of physical activity can lead to hypertension, as can being overweight, smoking and drinking too much alcohol. A child who can't manage stress, or who faces too much stress, may also be at increased risk.

The good news is, you can combat these issues by teaching your child heart-healthy habits that can reduce their risk of high blood pressure. For better heart health and overall wellness for your family, try these tips:

1. Make exercise a regular part of the routine — and make it fun! Unsure where to start? Sign your kid up for a sport they're interested in, swap Monopoly night for some tag, participate in a family 5K, or create a James Bond-type mission where you and your child try to hike every local trail by a certain date.
2. Tweak the menu. Making healthy adjustments to meals — especially in terms of lowering sodium and adding fresh fruits and vegetables — can have a positive effect on heart health and your family's risk of hypertension. Pinterest offers a wealth of ideas for healthy recipes and ingredient swaps, like using Greek yogurt for mayo. Filling your fridge with healthy ingredients and leaving junk food at the store can make healthy snacking an easy choice. To make healthy eating more interactive, have your children help out with the cooking. You might even consider planting a garden to help your kids understand the joys of growing their own healthy food.
3. Make treats nourishing. Eating healthier doesn't have to mean forgoing treats altogether. Bake them at home and make them more nutritious with smart ingredient swaps. Think unsweetened applesauce instead of butter, pure maple syrup instead of sugar and almond flour instead of white flour.
4. Help relieve your child's stress. One major stressor for your kid is likely school. Fox News advises ensuring your child gets enough sleep, silencing any criticisms about school work and limiting tech time. Instead of staring at a screen, you might try doing some yoga with your child — which also adds exercise to their day — or creating art in an anti-stress coloring book.
5. Take them for regular checkups. Remember, there are typically no symptoms associated with high blood pressure. So whether your child is overweight or slender, stressed or calm, they should still be thoroughly checked during an annual physical with their doctor.

More children may be facing high blood pressure than originally thought.

With new guidelines and screening tables, though, more families of children with high blood pressure can seek treatment and preventive measures. By focusing on routine checks and setting the foundation for lifelong healthy habits, you can help your child avoid high blood pressure in adulthood.