A blood pressure of 108/64 is a good reading. It falls well within the normal category, which covers any systolic (top number) below 120 and any diastolic (bottom number) below 80. For most people, this reading suggests a healthy cardiovascular system with no cause for concern.
Where 108/64 Falls in the Guidelines
The 2025 guidelines from the American Heart Association and American College of Cardiology break adult blood pressure into four categories:
- Normal: below 120/80
- Elevated: 120 to 129 systolic with diastolic still under 80
- Stage 1 hypertension: 130 to 139 systolic or 80 to 89 diastolic
- Stage 2 hypertension: 140 or higher systolic, or 90 or higher diastolic
At 108/64, both numbers sit comfortably in the normal range. You’re 12 points below the threshold for “elevated” on the top number and 16 points below on the bottom number. There’s no official low blood pressure cutoff in these guidelines because what counts as “too low” depends on whether you have symptoms, not on hitting a specific number.
Why This Reading Is Linked to Longevity
A large study published in Circulation tracked women across decades and found that a systolic pressure between 110 and 120 gave the highest probability of surviving to age 90. For diastolic pressure, the sweet spot was between 70 and 80. Your reading of 108/64 puts your systolic right near that optimal window. Your diastolic sits slightly below the 70 to 80 range that showed the strongest survival advantage, but only by a few points.
Women with systolic blood pressure between 110 and 130 at age 65 had a 37% probability of living to 90. That probability climbed at older ages simply because they’d already survived longer. The takeaway: keeping your systolic in the low-normal range throughout life is one of the strongest predictors of cardiovascular health over time.
When a Diastolic of 64 Deserves Attention
A diastolic reading of 64 is normal for most people, but context matters. Research from the Framingham Heart Study found that a diastolic pressure below 70 can raise cardiovascular risk in one specific scenario: when it’s paired with a wide pulse pressure (the gap between your top and bottom numbers) of 68 or more. That pattern typically shows up in older adults whose arteries have stiffened, pushing the systolic number high while the diastolic drops. Your pulse pressure is 44 (108 minus 64), which is well within a healthy range, so this concern doesn’t apply to you.
If you’re young, physically active, or naturally run on the lower side, a diastolic of 64 is completely unremarkable. Athletes, in particular, tend to have lower resting blood pressures. A study of nearly 3,700 athletes aged 19 to 40 found average readings of about 116/75 in women and 126/80 in men, with endurance athletes and those in artistic sports posting the lowest numbers. A reading of 108/64 fits right into the range you’d expect from someone who exercises regularly.
Signs Your Blood Pressure Might Be Too Low
There’s no hard number that defines “too low.” Instead, it’s about how you feel. Most health professionals only consider blood pressure problematic when it causes symptoms like:
- Dizziness or lightheadedness, especially when standing up
- Blurred or fading vision
- Fatigue that doesn’t improve with rest
- Trouble concentrating
- Nausea
- Fainting
If you feel fine at 108/64, it’s simply your normal. If you notice dizziness when you go from sitting to standing, that’s worth paying attention to. A drop of 20 points or more in systolic pressure, or 10 points or more in diastolic pressure, upon standing is considered orthostatic hypotension. Even a change of 20 points can be enough to make you feel faint. Staying hydrated and standing up slowly are the simplest ways to manage this if it happens occasionally.
Blood Pressure of 108/64 During Pregnancy
If you’re pregnant and wondering about this reading, 108/64 is well within the safe zone. Normal blood pressure during pregnancy is 120/80 or lower, and blood pressure often dips during the second trimester before rising again later. A reading of 108/64 is a healthy sign. The concern during pregnancy is blood pressure going too high (140/90 or above after 20 weeks), not readings in this range. That said, if low blood pressure symptoms like persistent dizziness or fainting develop, it’s worth mentioning at your next prenatal visit.
What to Do With This Reading
A single blood pressure reading is a snapshot, not a diagnosis. Blood pressure fluctuates throughout the day based on stress, hydration, caffeine, body position, and even the time you last ate. If you’re monitoring at home, take readings at the same time each day, sitting quietly for five minutes first, with your arm supported at heart level. Track your numbers over a week or two to get a reliable average.
If your average stays in the neighborhood of 108/64 and you feel good, you’re in an excellent position. This reading carries low cardiovascular risk, aligns with the blood pressure range linked to the longest life expectancy, and requires no intervention. Keep doing what you’re doing.