Blood Pressure: What's The Big Deal?

Written by Dr Su-Yin Yeong, Sydney Based General Practitioner

Blood pressure is one of those things I think not many people fully understand. Most people know it shouldn’t be too high. My non-medical mother, for example, is very fixated on those two little numbers resting on top of each other on the digital blood pressure machine screen.

But what does it actually mean? And why do us doctors care so much about those numbers?

Your blood pressure is made up of two numbers- the systolic blood pressure (the top number) and the diastolic blood pressure (the bottom number). The systolic number is your blood pressure when the heart is beating, and the diastolic is your blood pressure when the heart relaxes. These numbers are impacted by a number of things, including how stiff your blood vessels are, how efficient your heart is at working, genetic factors, whether you smoke or not, and so forth.

We aren’t usually too concerned about it unless it is too high, or too low.

We’ll start with low blood pressure first, or hypotension. In most people, hypotension is benign. Low blood pressure is quite common in young, fit people, especially young women. The only issue it can cause is if you stand up too quickly from a lying down position. The body needs to compensate for this change in body position, and gravity is pulling your blood down towards the ground. Hence if your blood pressure is normally low, there can be a bit of a delay in your blood pressure catching up with your body position. These patients often feel dizzy or lightheaded, or can get fuzzy black spots in their vision if they stand up too quickly. This is not usually a problem except for on really hot days or if the patient is dehydrated, because their blood pressure can drop even more and cause faints or blackouts.

If you ever experience these symptoms with chest pain, shortness of breath, a headache, or it is unusual for you, you should seek medical attention immediately.

Then there is the one we’ve all heard about, high blood pressure, or hypertension. High blood pressure is generally defined as systolic pressure of greater than 140mmHg, or diastolic blood pressure of greater than 90mmHg. We all know high blood pressure is a risk for all sorts of things- heart attacks, strokes, and so forth- the things that kill us. 

But why?

There’s a number of reasons, but the main one that I always explain to my patients is that blood pressure is the pressure gradient your heart has to work against. So if you have high blood pressure, your heart has to work harder to overcome this pressure and allow blood to flow to the rest of your body. Over time this causes stress on the heart, and can result in heart failure and heart attacks. Most of the time high blood pressure doesn’t even cause any symptoms, unless it’s really high, so you could have high blood pressure without even knowing it.

So what can we do about it?

Exercise: 

I’m always going on about it, but I really can’t emphasise it enough. Moderate intensity exercise is really good for your heart and your blood pressure. While any type of movement is good for weight maintenance, exercise that makes you huff-and-puff is really good for cardiovascular fitness. So I always tell my patients who love to walk, add in a hill or a staircase to your daily work, just to get in some heart and blood vessel training.

As always, please check with your doctor before you start any exercise program, particularly if you have heart problems. Patients with known heart problems have to be a bit more careful when it comes to exercise.

Quit smoking:

Or if you aren’t a smoker, don’t start. Smoking, along with the many other problems it causes, is a known risk factor for hypertension due to its blood vessel stiffening effects.

Lose weight:

Through a healthy diet and exercise. Being overweight increases your blood pressure as a higher pressure is needed to supply blood to your tissues and organs.

Don’t be scared of medication:

If you’re already doing all of the above, and your blood pressure is still too high and your doctor wants to start you on medication, don’t be scared of it! Getting your blood pressure to a normal level is protecting your heart and your brain. There are side effects, but there are ways to manage this and many options for medications, so please, listen to your doctor.

If you would like to see me and have your blood pressure checked, or if you would like to see me to discuss weight loss management, please check out my contact details or click here to book an appointment.

First published on her Blog "The Wellbeing Doctor".

See the original piece here.