A blood pressure of 117/66 falls in the normal category. The 2025 guidelines from the American Heart Association define normal blood pressure as below 120/80 mmHg, and both your numbers land comfortably under those thresholds. For most people, this is a healthy reading that doesn’t require any intervention.
Where 117/66 Fits in the Guidelines
Blood pressure is grouped into four categories for adults: normal (below 120/80), elevated (120-129 systolic with diastolic still under 80), stage 1 hypertension (130-139 systolic or 80-89 diastolic), and stage 2 hypertension (140+ systolic or 90+ diastolic). Your reading of 117/66 sits in the normal range, and current guidelines actually encourage most adults to stay below 120/80 for the best cardiovascular protection.
It’s also well above the threshold for low blood pressure. Hypotension is generally defined as a reading below 90/60, so 117/66 has a wide margin above that cutoff.
The Diastolic Number Worth Watching
Your systolic number (117) is solidly healthy, but the diastolic reading (66) is worth understanding in context. The diastolic number reflects the pressure in your arteries between heartbeats, when your heart is filling with blood. It’s also the phase when blood flows into the coronary arteries that feed the heart muscle itself.
Research published by Harvard Health found that people with diastolic readings between 60 and 69 were twice as likely to show subtle signs of heart damage compared to people with diastolic pressures of 80 to 89. Over a 21-year follow-up, diastolic pressures below 70 were also associated with a higher risk of heart attack and hospitalization for heart failure. This matters most for people who already have heart disease, because clogged coronary arteries rely on adequate diastolic pressure to push blood through narrowed channels. When that pressure drops too low, parts of the heart muscle may not get enough oxygen.
For a healthy person without heart disease, a diastolic reading of 66 is not a concern. But if you’re on blood pressure medication or have known coronary artery disease, it’s worth confirming with your doctor that your diastolic isn’t being pushed too low in the effort to control the top number.
Your Pulse Pressure Is Normal
Pulse pressure is the gap between your two numbers. For 117/66, that’s 51 mmHg. A normal pulse pressure is around 40 mmHg, and values of 50 or above can slightly increase cardiovascular risk over time, including heart disease, arrhythmias, and stroke. Your reading of 51 is just at that threshold, which is common and not alarming on its own. Truly widened pulse pressure starts around 100 mmHg. Still, if your pulse pressure trends higher over time, it could signal stiffening arteries, something that becomes more relevant with age.
When a Normal Reading Could Still Be Too Low
Blood pressure numbers don’t tell the whole story. What matters just as much is how you feel. Some people run naturally low and feel perfectly fine. Others might experience symptoms at pressures that technically look normal on paper. Signs that your blood pressure may be too low for your body include dizziness or lightheadedness, fainting, blurred vision, unusual fatigue, nausea, difficulty concentrating, and fast shallow breathing.
Many people with lower blood pressure never notice any symptoms at all. If you’re one of them, your reading is simply your healthy baseline. If any of those symptoms are disrupting your daily routine, that’s worth bringing up at your next appointment, even though the number itself looks fine.
Keeping Your Blood Pressure in This Range
If your blood pressure is already normal, the goal is to keep it there as you age. Blood pressure naturally tends to rise over time, so the habits you maintain now have a compounding effect. The CDC recommends at least 150 minutes of moderate-intensity exercise per week, roughly 30 minutes a day, five days a week. Brisk walking and cycling both count.
On the dietary side, the DASH eating plan has the strongest evidence for blood pressure maintenance. The core principles are straightforward: eat more foods rich in potassium, fiber, and protein while cutting back on sodium and saturated fat. In practical terms, that means more fruits, vegetables, whole grains, and lean proteins, with less processed food, red meat, and added salt. These aren’t dramatic changes, but they’re the ones most consistently linked to keeping blood pressure in the normal range long-term.