When Is Blood Pressure Lowest and Highest During the Day?

Your blood pressure fluctuates throughout the day. Check your blood pressure twice a day at around the same time every day.

Globally, over one billion people have high blood pressure (HBP), also known as hypertension. If you too have similar problems, your doctor may have advised you to check your BP regularly. To be as accurate as possible, you should first figure out what would be the best time of day to do so. The answer be personal and will depend upon your schedule and the method you wish to follow to monitor your blood pressure.

Your blood pressure fluctuates throughout the day. So, to get the most accurate picture, you should check your BP at least twice daily. 

Strictly speaking, there is no best time to take blood pressure. The key to getting accurate blood pressure readings is to check your BP regularly at the same time each day. This means you need to choose the times that are most convenient for you, as you need to stick to them every day.  

You can select the times when you know you'll be free and the least distracted. For example, you can make it a habit to monitor your blood pressure before you leave for work, before having dinner, and before going to sleep.

There are many factors that can affect your blood pressure readings. 

Time of the day

Blood pressure has a daily rhythm. It rises and falls at different times during the day. Your blood pressure drops during the night and is 10% to 20% lower while you're asleep. It starts to rise a few hours before you wake up and is the highest during the middle of the day. By late afternoon and evening, it starts to fall again. 

Experts recommend not to take your blood pressure immediately after waking up. Rather, you should wait for at least 30 minutes after waking before you take a BP reading.

Food and caffeine

Both food and coffee can increase your blood pressure. Ideally, you should take your morning blood pressure after you have brushed and showered but before you've had your breakfast. 

Lifestyle factors

There are some activities you need to avoid for at least half an hour before taking your blood pressure reading, no matter the time of the day. These include:

• Exercising
• Smoking
• Drinking alcohol
• Using tobacco

You can monitor your blood pressure at home or get it checked at your doctor's office. Each way has its benefits and drawbacks. The best approach for you would be to combine both methods to get a complete understanding of your blood pressure. 

Get BP checked by a medical professional

It is common for a doctor to check your blood pressure during a medical appointment. If you have serious BP-related issues, your doctor may ask you to schedule your appointments during different times of the day. This will help your doctor determine your average BP range and get an accurate picture of your blood pressure. 

However, since it's not possible to visit a medical office every day, most people don't find it a convenient way of regularly monitoring their blood pressure. Therefore, blood pressure checks at a medical office are only recommended for serious BP-related cases or when the regular involvement of a doctor is required.

Check BP at home

Most people prefer to check BP at home using a blood pressure monitor. It is comparatively simpler, cheaper, and at times, produces even better results than getting tested by a medical professional. This is because home blood pressure checks can help you avoid the white coat effect — the condition where BP readings remain normal at home but rise at the doctor's office due to anxiety felt by patients. 

With home monitoring, you can track your BP daily and throughout the day whenever it's convenient for you. Home blood pressure checks are also useful when you need to test the effect of a new BP medicine or a new low-salt diet.  With respect to home monitoring, the only important thing to know is how to use a blood pressure monitor correctly and get accurate readings from it.

While you're at the doctor's office, a medical professional will make sure to follow the best practices while monitoring your BP. However, if you're using an at-home BP monitor, you need to follow these tips to get accurate blood pressure readings:

• Make sure your room is comfortable and warm.
• Take 5 minutes to relax before starting the blood pressure test.
• Prefer to sit in a chair with your feet firmly placed on the floor.
• Support the arm you'll be using on a table or a flat surface while maintaining your elbow at heart level.
• Make sure the inflatable part of the cuff touches your bare skin while covering at least 80% of your upper arm.
• Avoid speaking while taking the measurement.
• Check your blood pressure twice, with a break of about 3 minutes between the measurements. Repeat it for the third time if there is a difference of 5 points or more between the readings.
• The blood pressure reading in the right arm and left arm can show differences. So, if possible check your BP using each arm at least once, and take the highest value for your consideration.

Your blood pressure is the measure of the force your heart uses to pump blood throughout the blood vessels in your body. It is shown by two numbers, where the first number indicates the systolic pressure. This is the pressure in your arteries during a heartbeat. The second number is called diastolic pressure. It represents the pressure in your arteries when your heart rests between two beats.

A blood pressure reading of 120/80 millimeters of mercury (mm Hg) is considered healthy. Readings above 130/80 and higher indicate high BP whereas readings below 100/60 indicate low BP. Getting high or low BP once or twice is not a matter of concern. But if you repeatedly get abnormal readings, talk to a doctor to get your BP in the healthy range. 

However, before you seek medical help, make sure you've followed the best practices while checking your BP at the same time every day. If needed, ask a medical professional to take your readings so that you get a more accurate picture and know for sure if there are any problems with your blood pressure.