Knowing when to take your blood pressure can help you predict your likelihood of suffering a heart attack. We know that having high blood pressure markedly increases your risk for heart attacks. Blood pressure is usually lowest just before you go to bed at night and when you first wake up in the morning. People can have high blood pressure only during the day or only at bedtime or during both the day and at bedtime.
In one study, researchers followed 891 patients, average age 64, for 4.7 years, with both high blood pressure and arteriosclerosis (Blood Pressure, April 2014;23(2):96-101). Since blood pressure is usually lower at bedtime, normal values for blood pressure during the day were defined as 140/90 and during bed-time 120/70. In this study, 25.7 percent of the subjects had normal daytime BP (less than 140/90), and 37.8 percent had a normal night-time BP (less than 120/70). They found that having high blood pressure during the day increased chance of dying of a heart attack by 180 percent, while high blood pressure at bed time increased the chance of dying of a heart attack by 163 percent.
I recommend that everyone should have their own arm blood pressure cuff (wrist cuffs are not very dependable). They are inexpensive and are available at any pharmacy. Take your blood pressure during the day and also at bedtime for a week. If the average of these readings is higher than 140/90 during the day, or 120/70 at bed time, or both, you have high blood pressure. If you have high blood pressure, you usually need to:
• lose weight,
• eat a diet that is high in fruits and vegetables,
• avoid sugared drinks and sugar-added foods, red meat and fried foods,
• get plenty of exercise,
• get your blood levels of hydroxy-vitamin D above 30 ng/mL.
Your doctor may also prescribe medication until your lifestyle changes bring your blood pressure back to normal. See my report on Blood Pressure Guidelines