You’re probably aware that your blood pressure temporarily rises under certain circumstances, like right after a tough workout or a salty meal. If you’re monitoring your blood pressure, you may be wondering when the best time of day is to take your blood pressure, so you get the most accurate reading possible.
While on the surface this may seem like an unnecessary concern, if you only take your blood pressure readings at a time of day when your blood pressure is at its highest, or, conversely at its lowest, you could have the wrong impression about your blood pressure risk. The outcome? You could be overmanaging, undermanaging, or completely neglecting your blood pressure.
This is why taking blood pressure readings at your body’s optimal time each day is a good idea. However, the right time to take blood pressure readings depends on your lifestyle and daily routine. In this guide, we will explore when to take blood pressure readings and provide general tips for collecting reliable data.
When should you take your blood pressure?
Blood pressure fluctuates continuously throughout the day. Your resting blood pressure is likely to be at its lowest first thing in the morning and is usually at its highest during, and straight after, exercise.
In the first instance, the best method to assess your overall blood pressure is to take multiple readings at different times of the day to get an average blood pressure level.
Once you have these baseline readings, you can then choose which time of day gives you the most accurate reading for your body.
Factors that can affect your readings
Blood pressure can be affected temporarily by the following factors (although there are others):
- Eating a substantial snack or a meal can lower blood pressure because your blood is directed to your digestive system. However, if you eat a highly processed or salty meal, your blood pressure may rise.
- Drinking caffeinated beverages. Caffeine can cause an increase in heart rate, which can increase your blood pressure.
- Smoking is a well-established cause of elevated blood pressure.
- Exercising may reduce your average blood pressure over time, but your blood pressure rises during a workout and for a period thereafter.
- Regular alcohol consumption can lead to hypertension.
- Taking medication. Blood pressure medications are designed to lower your blood pressure, however other medications such as decongestants, antidepressants, and others may raise your blood pressure.
It is always best to take your blood pressure reading when you’ve not engaged in any of the activities above for a short time. A good rule of thumb is to leave 30 minutes between doing any of the activities above and taking a blood pressure reading.
What time of day is blood pressure highest
Typically, blood pressure is at its lowest upon waking and just before sleep, and peaks in the middle of the day. Still, it’s highly individual and, depending on your unique makeup and habits, blood pressure peaks at different points throughout the day. If you’re taking multiple readings as the day goes on, you can start recognizing patterns and plan your blood pressure readings accordingly.
High blood pressure at night
Some people experience high blood pressure at night, known as nocturnal hypertension. If you notice that your blood pressure readings at night are high when compared with your daily readings, you might look into the causes. Some of the more common ones include:
- Sleep apnea: when you stop breathing during sleep it sets off your body’s innate panic button to wake you so that you resume breathing. This surge of stress will elevate your blood pressure.
- Rapid eye movement (REM) sleep phase: the dream state. Some people have arousing or frightening dreams that might cause an increase in heart rate and blood pressure.
- Nocturia: the need to get up and urinate in the middle of the night.
Even if it seems minor to you, elevated blood pressure at night is associated with cardiac events and organ damage if it’s severe enough. Your doctor may want to help you manage your blood pressure at night as a preventive measure.
If you notice your blood pressure is higher at night, be sure to take a few readings during the day as well so that you and your doctor can assess your blood pressure pattern over time.
High blood pressure in the morning
High blood pressure in the morning is known as morning hypertension, and it’s defined as a blood pressure elevation that occurs between 6:00 am and 10:00 am. While it is not thoroughly understood, one of the potential causes is activation of the sympathetic nervous system; when your body shifts from automatic processes like breathing and heart beating to active processes like walking and eating. Another possible cause is inadequate use of blood pressure medications.
If you notice your blood pressure readings are unusually high in the mornings, be sure to measure your blood pressure during the day as well so that you and your doctor can establish a pattern and decide the best path forward.
How do you measure blood pressure?
There are various ways to take a blood pressure reading. The method most people are familiar with is the use of a sphygmomanometer, an inflatable arm cuff for measurement of systolic and diastolic blood pressure.
General steps for taking a blood pressure reading using a BP cuff:
- Familiarise yourself with the device to ensure you follow the correct steps
- Sit in a relaxed seated position
- Rest your arm on a flat surface such as a table and allow the device to take a reading
- Take another reading 3 minutes later
- Make a note of the readings
It is best to keep your blood pressure notes over time in one place so that you can share your results with your doctor.
Most people realize that high blood pressure should be discussed with your doctor, but keep in mind that your doctor should know about low blood pressure readings too, as low blood pressure can also require medical management.
This manual process is effective but requires discipline to carry out on a daily basis.
Technological developments have created more subtle blood pressure monitoring devices that can be worn throughout the day. Blood pressure wrist monitors, such as that from Aktiia, can take automated readings throughout the day to provide numerous convenient and accurate readings.
This is particularly useful when trying to gather data on nighttime blood pressure, as there is a substantial body of research that shows nighttime blood pressure is more highly correlated to cardiovascular risk than standard daytime blood pressure measurements.
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What is a healthy blood pressure reading?
The typical ranges of low, normal and high blood pressure are defined by the European Society of Hypertension (ESH) as:
- Optimal – Less than 120 systolic, less than 80 diastolic
- Normal – 120–129 systolic, 80–84 diastolic
- High normal – 130–139 systolic, 85–89 diastolic
For more information on blood pressure readings, read our guide on blood pressure monitoring.
FAQ About the Time of Day to Take Blood Pressure Readings
What if I work irregular hours?
People who have irregular shift patterns will understandably find it difficult to take regular blood pressure readings. Even just taking a single daily reading will help monitor your health.
Standard cuff blood pressures require a person to plan when they take their blood pressure.
There are, however, new blood pressure sensors that can be worn on the wrist and take automated and continual readings up to 12 times a day, which can be particularly useful and convenient to increase the amount of blood pressure data available to you and your medical team.
What is the best time to take blood pressure readings?
For many people, the best times to take a reading are in the morning before work, in the evening after work, and just before bed. Alert your doctor if you measure unusually high or low readings in the morning or late evening.
When is the best time to take blood pressure medication?
If you measure your blood pressure at multiple points throughout the day for several days, you will notice when your blood pressure typically rises. You may choose to take your medication before your blood pressure rises, but as always, ask your doctor for guidance on when to take any prescription.
Summary
The most important aspect of blood pressure monitoring at home is to check your blood pressure routinely. For many people the best time to take a reading is first thing in the morning before breakfast and last thing at night before bed. It is important to avoid drinking, eating, smoking or exercising 30 minutes before taking a reading to ensure it is accurate.
Readings have traditionally been conducted using an inflatable arm cuff, but modern blood pressure monitors such as Aktiia’s continuous blood pressure monitor can passively and automatically take readings around the clock.
Disclaimer: This article is for informational purposes only and does not contain medical advice, and is not a replacement for medical advice. The information in this article is not intended to diagnose, treat, cure, or prevent any disease. Talk to a qualified medical professional before making any changes to your health regimen.
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