Your doctor’s office could be reading your blood pressure all wrong - Ars Technica

I learned about the correct method of checking blood pressure from an episode of Peter Attia's podcast a while back. It does make a notable difference when you do the test.

According to the American Heart Association and other medical experts, getting an accurate reading requires following a strict set of preparations: You must not eat, drink, exercise, or smoke within 30 minutes of a reading. You must have an empty bladder. You must sit straight up in a chair with back support. Your legs must be uncrossed and your feet must be flat on the ground. The arm to be measured must be rested on a flat surface so that it is at the same level as your heart, not lower, not higher. You must sit calmly, without talking for five minutes to relax before the reading. When it's time, an appropriately sized cuff should be wrapped around your bare upper arm, right above the elbow; it should never be wrapped over clothing. At least two readings should be taken, with the average recorded. Ideally, readings should be taken in both arms, with the highest readings recorded.

The downside of this though is that it means taking your blood pressure goes from a couple of minutes to taking like 15 minutes — which for me at least means I test it much, much less frequently.