Managing high blood pressure

Learn about high blood pressure (hypertension), what you can do to lower it and how to understand blood pressure readings.

In this article

What is blood pressure?

Your heart pumps blood around your body through a network of vessels (tubes) called arteries. With each heartbeat the blood pushes against the artery walls. The strength of this 'pushing' is your blood pressure (pēhanga toto).

Your blood pressure changes throughout the day. It's lower when you're asleep or relaxing and goes up when you move around. It can also be increased by stress or extreme emotions and stimulants like nicotine or caffeine.

Some people's blood pressure stays above recommended levels. This is known as high blood pressure (hypertension). This can lead to damaged arteries and increase your risk of:

This can happen for a range of reasons and there's a number of things you can do to reduce your blood pressure.

How is blood pressure measured?

Blood pressure is measured using a machine called a blood pressure monitor.

A cuff (thick band) is put over your arm. This cuff is attached to a machine which measures the pressure inside your arteries. When the machine is switched on the cuff tightens and then slowly loosens again. It is quick and painless. At the end, the machine will give a blood pressure reading.

Blood pressure is measured in millimetres of mercury (which is written as mmHg).

A blood pressure reading contains two numbers and will be written as a figure like 120/75 (this is said as '120 over 75'.)

The first (top) number is the pressure when your heart beats (systolic pressure). The second (bottom) number is when your heart relaxes (diastolic pressure).

arm with a blood pressure cuff wrapped around the top of it. Blood pressure monitor showing systolic and diastolic blood pressure readings.

During a blood pressure test, a blood pressure cuff is wrapped around your arm so a blood pressure monitor can measure your systolic and diastolic blood pressure.

Where do I get my blood pressure tested?

You can get a blood pressure reading at your GP practice and at most local pharmacies. You may also choose to have a blood pressure monitor at home.

What is a normal blood pressure reading?

For most people an ideal blood pressure is 120/75, or lower.

However, the blood pressure that is 'ideal' for you depends on many factors, including your overall risk of heart attack and stroke.

If you’re already on high blood pressure medication, your ideal blood pressure will be 130/80 or below.

What is high blood pressure (hypertension)?

High blood pressure is when your blood pressure is regularly higher than recommended levels. The clinical term for this is hypertension.

A single high blood pressure reading doesn't necessarily mean you have hypertension.

You have hypertension if your blood pressure stays high for three separate readings, on three separate occasions, over at least three months.

Sometimes people's blood pressure goes up because they're worried about having it taken by the nurse or doctor. If this is a problem, the doctor may get you to do blood pressure readings at home or order a 24-hour monitor to help confirm you have high blood pressure.

Home blood pressure monitoring

Some people buy their own blood pressure monitor to use at home. This means you can measure your blood pressure on an ongoing basis.

The blood pressure readings you do at home are as good as those done by your doctor.

If you decide to buy one, it's important to get the correct cuff size. If the cuff is too big or too small, it can give an inaccurate reading.

If you take your own blood pressure and get an unusually high reading, take it a second time after at least five minutes. If it's still high and you're worried, contact your nurse or GP.

What causes high blood pressure? 

For most people, there isn't a single cause of high blood pressure. However there are a number of things that make you more likely to have it. These are called risk factors.

Some risk factors for high blood pressure you can manage, for example when you:

  • Smoke or vape with nicotine. When you smoke or vape nicotine your blood pressure goes up. Over time it damages your arteries, increasing your risk of a heart attack or stroke.
  • Eat too much processed foods and salt. Many processed foods include a lot of salt. Too much salt makes your body store extra water which raises your blood pressure.
  • Drink too much alcohol too often. Drinking alcohol temporarily increases blood pressure. Over time, drinking too much on a regular basis can lead to long-term increases in blood pressure.
  • Are overweight. Being overweight increases your risk of having high blood pressure. Even losing just a few kgs can lower your blood pressure.
  • Aren't active enough. Moving more and sitting less will lower your blood pressure.
  • Are stressed. The hormones released in your body when you’re stressed increase your blood pressure. Researchers are still trying to understand the exact link between long-term high blood pressure and ongoing stress.

Other risk factors include:

  • Diabetes. If you have type 1 or type 2 diabetes, you’re twice as likely to get high blood pressure.
  • Having kidney disease or other glandular problems. Sometimes another condition that affects your kidneys, arteries, heart or endocrine (gland) system can cause high blood pressure.
  • Getting older. Blood pressure naturally increases with age.
  • Taking certain medications, such as birth control pills. Ask your pharmacist about the side-effects of any medication you take.
  • Having a parent or brother or sister with high blood pressure. High blood pressure runs in family, so find out if your parents or siblings have had a problem with this.

Symptoms of high blood pressure

High blood pressure is often called the 'silent killer' because in most cases it doesn’t have any symptoms.

The only way to find out if you have it is to get your blood pressure checked by your doctor, nurse or pharmacist.

How to lower blood pressure

There are lots of things you can do to lower your blood pressure.

If your doctor has given you blood pressure medication, take it as prescribed. However, you'll also need to follow a heart-healthy lifestyle.

Even if you haven't been diagnosed with hypertension, following these tips will be good for your blood pressure and good for your heart.

Quit smoking

Stopping smoking is a great thing you can do for your blood pressure and your heart health.

Ask your doctor or nurse for help.

Phone Quitline 0800 778 778, or visit quit.org.nz for information and support.

Eat more heart-healthy foods and less salt

What you put into your body can make a big difference to your blood pressure.

Eat a wide variety of heart-healthy foods like:

  • whole grains
  • legumes and pulses
  • nuts and seeds
  • fruits and vegetables
  • oily fish.

Eat less foods that are high in salt (sodium), like:

  • takeaways and ready-made meals
  • shop-made baked items like biscuits and cakes (which are often high in salt as well as sugar)
  • savoury snacks like crisps and sausage rolls.

Instead of using salt, try these to give your food flavour:

  • herbs and spices
  • chilli
  • garlic
  • onion
  • curry powder
  • lemon or
  • vinegar.

Read food labels – less is best of the three Ss (salt, sugar and saturated fat).

Read more about eating less salt.

Drink less alcohol

Less alcohol means lower blood pressure and less unnecessary calories.

Have at least two alcohol-free days a week.

Drink no more than 1 to 2 standard drinks per day if you're female, or no more than 2 to 3 if you're male.

If you have high blood pressure, or you've been diagnosed with a heart condition, you may need to drink less than this.

One standard drink is:

  • a standard can of 4% beer (300ml)
  • a small glass of wine (100ml)
  • a small single shot of spirits (25mls).

 Read more about alcohol and heart health.

Move more

Being more active is a great way to lower your blood pressure. Ideally you should do 30 minutes of activity a day. If you can’t do it all in one go, it can be short bursts of activity which add up to 30 mins.

You could try:

  • using the stairs not the lift
  • parking 10 minutes away from your work or getting off the bus a stop early.
  • walking the dog twice around the park instead of once.
  • taking a walk outside during a break at work.
  • having a swim or walk at the beach with family.
  • doing half an hour of gardening or cleaning.

Read more about the benefits of exercise.

Manage stress

Researchers are still trying to understand the exact link between stress and long-term high blood pressure. However being stressed contributes to other risk factors like poor diet and drinking more alcohol.

You can't always remove the sources of stress in your life. But here are some things you can do to manage them.

  • Enjoy exercise every day, like taking a walk.
  • Take a break for yourself.
  • Get 7-8 hours plus sleep each night.
  • Talk about how you are feeling.
  • Try relaxation music or breathing exercises.

Blood pressure medication

Your doctor may suggest you take medication to lower your blood pressure. Taking this medication as directed will help lower your chance of having a heart attack or stroke.

Medications used to treat high blood pressure include:

Your doctor will decide what type of pills and the dose that's best for you.

The benefit of taking blood pressure medication usually outweighs any side-effects. Talk to your doctor if you're worried. Sometimes they can change the type of medication that you're on or adjust your dose. Never stop taking your medication without talking to your doctor first.

Find out more about managing heart medication.

Read about other heart disease risk factorsHear from people with high blood pressure