Unless your family has a history of high blood pressure or your doctor has warned you about your own reading, chances are you haven’t given this potentially serious and far-reaching medical condition much thought.

"People don’t usually know they have high blood pressure unless they get it measured," explains Dr. Chris Simpson, a cardiologist and Vice-Dean (Clinical) at Queen’s University’s School of Medicine in Kingston, Ontario. In fact, you can have high blood pressure for years without symptoms. "When people are diagnosed in their 40s or 50s, they’ve often had high blood pressure for a while."

This is a shame, because early detection can be the key to maintaining the health and proper function of your heart, kidneys, vision and more.

The following guide will walk you through the basics of blood pressure and offer tips on how to keep yours within a healthy range.

Systolic and diastolic blood pressure: What do they mean?

When your doctor talks about blood pressure, she’s actually talking about two numbers: systolic and diastolic.

Systolic blood pressure is the top number in your reading. It measures the pressure when your heart pumps blood through your vessels.

Diastolic blood pressure — the bottom number — measures the pressure when your heart is resting between beats.

So, for example, if you have a reading of 116/78, that indicates a systolic blood pressure of 116 and a diastolic blood pressure of 78. It would also fall squarely within the healthy range. A reading below 120/80 is considered a low risk to your health, according to the Heart and Stroke Foundation of Canada.

A reading between 121/80 and 139/89 — sometimes described as pre-high blood pressure or pre-hypertension — is considered a moderate risk. And a reading of 140/90+, also called high blood pressure or hypertension, constitutes a high health risk. If you have diabetes, the high-risk category starts lower, at 130/80.

While you may have heard that your systolic reading (the top number) is more important in predicting your heart attack and stroke risk, that isn't always true. High systolic or diastolic pressure can damage your blood vessels over time and put your health at risk.

What factors affect your blood pressure?

You're probably aware of some of the causes of high blood pressure: A sedentary lifestyle, a diet high in sodium and a lack of access to health care all contribute to your risk. But other factors also affect your hypertension risk. A family history of high blood pressure means you're also more likely to develop it, and people of African, South Asian and Indigenous heritage face an increased risk of developing high blood pressure, explains the Heart and Stroke Foundation. And you'll face a higher chance of developing hypertension as you age.

Understanding the risk of high blood pressure is also especially important for women. Conditions that can occur during pregnancy, like pre-eclampsia or gestational diabetes, can contribute to the risk of high blood pressure both during pregnancy and later on. And the age-related risk of hypertension is compounded for women, since menopausal hormonal changes also contribute to high blood pressure.

How elevated blood pressure affects your health

Though it’s likely no surprise that elevated blood pressure puts your health at risk, some of its effects on your health might surprise you. Not only does elevated blood pressure increase your risk of heart disease and stroke, it also places you at a higher risk of kidney failure, blindness and other health issues related to your blood vessels, Dr. Simpson explains. On top of that, high blood pressure is the most common cause of a rapid, irregular heartbeat, he says, which is an increasingly common heart problem for many Canadians.

If your blood pressure is in the pre-high blood pressure range, you could also face an increased risk of health complications, Dr. Simpson explains, but you are still in a stage that frequently responds well to lifestyle changes.

How to keep your blood pressure in a healthy range

When it comes to managing your blood pressure, the simple fixes often cited for many maladies — that is, a healthy diet and regular exercise — work best, says Dr. Simpson. Aim for at least 150 minutes of brisk walking per week to help manage your blood pressure, he advises, and follow a healthy diet that keeps your salt consumption in check.

If you have elevated blood pressure that’s not responding to lifestyle changes, ask your doctor about medication to protect your health.

Keep in mind that other factors such as high levels of stress may also increase your blood pressure and raise your risk of other blood vessel-related problems. So make stress management a part of your daily routine. And if you’re struggling with financial stress, find an advisor near you to help put your mind — and your heart — at ease.