A diastolic blood pressure below 60 mmHg is generally considered low. The diastolic number is the bottom reading in a blood pressure measurement, representing the pressure in your arteries between heartbeats, when your heart is resting and refilling with blood. While normal diastolic pressure falls below 80 mmHg according to the 2025 AHA/ACC guidelines, the healthy sweet spot sits between 70 and 80 mmHg.
Where the Threshold Sits
Blood pressure is recorded as two numbers: systolic (top) over diastolic (bottom). The current clinical framework classifies normal blood pressure as below 120/80 mmHg, but “normal” and “low” aren’t the same thing. A diastolic reading in the 60s is perfectly fine for most people and causes no symptoms. Once it drops below 60 mmHg, though, the risk picture changes.
A large study of U.S. adults with normal systolic pressure found that those with diastolic readings below 60 mmHg had a 30% higher risk of death from any cause compared to people whose diastolic pressure fell between 70 and 80 mmHg. The risk of cardiovascular death specifically was 34% higher. This held true even among people who weren’t taking blood pressure medications, where the risk was 46% higher. Researchers describe this as a “J-shaped” pattern: risk rises at both the high and low ends of the diastolic range.
There’s no single official cutoff for “too low” the way there is for high blood pressure. The general hypotension threshold of 90/60 mmHg is widely used, meaning a diastolic reading of 60 or below paired with low systolic pressure clearly qualifies. But diastolic pressure can drop on its own while systolic stays normal or even elevated, which creates a different set of concerns.
Why Diastolic Pressure Drops
Your heart muscle gets most of its own blood supply during the diastolic phase, the brief pause between beats. When diastolic pressure falls too low, the coronary arteries may not fill adequately, reducing oxygen delivery to the heart itself. This is why cardiologists pay close attention to low diastolic numbers, especially in people who already have heart disease.
The most common reason diastolic pressure falls with age is stiffening of the arteries. Young, healthy arteries are elastic. They stretch when the heart pumps and then recoil between beats, maintaining steady pressure. As arteries lose elasticity over the decades, they absorb less of the pulse wave. Systolic pressure climbs (because stiff vessels can’t cushion the surge) while diastolic pressure drops (because they can’t sustain pressure between beats). This pattern, called isolated systolic hypertension with a wide pulse pressure, is extremely common in older adults and can make treatment tricky: lowering the top number with medication may push the bottom number dangerously low.
Other factors linked to low diastolic pressure include heart failure, prior heart attack, diabetes, dehydration, and certain medications. Blood pressure drugs are an obvious contributor. In elderly patients especially, aggressive treatment of high systolic pressure can inadvertently cause diastolic readings to fall below safe levels.
Symptoms to Recognize
Many people with mildly low diastolic pressure feel nothing at all. Symptoms typically emerge when the drop is significant or sudden. A pressure change of just 20 mmHg can produce noticeable effects. Common signs include dizziness or lightheadedness, blurred or fading vision, fatigue, difficulty concentrating, fainting, and nausea.
Severe drops can lead to signs of shock: confusion (particularly in older adults), cold and clammy skin, pale complexion, rapid shallow breathing, and a weak, fast pulse. This is a medical emergency.
How It Gets Evaluated
If your diastolic readings are consistently below 60 mmHg, especially with symptoms, your doctor will likely start with repeated blood pressure checks in both sitting and standing positions. A drop of 10 mmHg or more in diastolic pressure within a few minutes of standing suggests orthostatic hypotension, a condition where your body struggles to adjust blood pressure when you change position.
Beyond that, common tests include blood work to check for anemia or low blood sugar, an echocardiogram to look at heart structure and function, an electrocardiogram to assess heart rhythm, and sometimes a tilt table test. During a tilt table test, you lie strapped to a table that gradually shifts from flat to upright while your blood pressure and heart rate are continuously monitored. This helps reveal how well your nervous system regulates circulation.
Raising Low Diastolic Pressure
If medication is driving your diastolic pressure too low, adjusting the dose or switching drugs is the most direct fix. This is a conversation to have with whoever prescribed the medication, since the goal is balancing the risk of high systolic pressure against the harm of low diastolic pressure.
For immediate relief during a low-pressure episode, lying down helps because your blood vessels no longer have to fight gravity. Drinking water increases blood volume and improves circulation. Squeezing a stress ball or making a tight fist activates your muscles, which pushes blood back toward your core and can nudge pressure upward. Cooling off also helps if heat or a warm environment triggered the drop.
Staying well-hydrated day to day is one of the simplest long-term strategies. Adequate water intake supports blood volume, which directly affects how much pressure your circulatory system can maintain. For people prone to dips, eating smaller, more frequent meals can prevent the post-meal blood pressure drops that happen when blood flow shifts toward digestion. Compression stockings reduce blood pooling in the legs and are particularly useful for older adults with orthostatic symptoms.
The ideal diastolic range for most adults is 70 to 80 mmHg. If your readings consistently sit below 60 and you’re experiencing symptoms, or if you have existing heart disease, that number deserves attention rather than dismissal.