Low diastolic blood pressure, the bottom number in a blood pressure reading, is generally considered concerning when it drops below 60 mmHg. Unlike low blood pressure overall, a low diastolic number can exist even when systolic pressure (the top number) looks perfectly normal. Raising it involves a mix of addressing underlying causes, adjusting medications, and making specific lifestyle changes that support blood volume and vascular tone.
Why Diastolic Pressure Drops
Diastolic pressure reflects what’s happening in your arteries between heartbeats, when your heart is refilling with blood. This is also the phase when blood flows into the coronary arteries that feed the heart muscle itself. So when diastolic pressure is too low, the heart may not get enough oxygen and nutrients during its brief rest period.
The most common reason diastolic pressure drops is aging. Before age 50, both the top and bottom numbers tend to rise together. But around age 50, diastolic pressure plateaus and then starts declining, while systolic pressure keeps climbing. This happens because the large arteries near the heart gradually stiffen over time. In a younger person, those flexible arteries stretch during each heartbeat and then recoil, pushing blood forward during the resting phase and maintaining diastolic pressure. When those arteries become rigid, more blood gets pushed through during the heartbeat itself (raising systolic pressure) and less gets redistributed during the resting phase (lowering diastolic pressure).
Dehydration, prolonged bed rest, nutritional deficiencies (especially B12, folate, and iron), and certain heart conditions like aortic valve problems can also pull diastolic pressure down. But one of the most common and fixable causes is medication.
Medications That Lower Diastolic Pressure Too Much
Blood pressure medications are the most frequent culprit. Diuretics (water pills), alpha blockers, and beta blockers can all overshoot their target and push diastolic pressure below a healthy range. If you’re taking any of these and your bottom number has been trending low, that’s a conversation worth having with whoever prescribed them. A dose adjustment or switch to a different class of medication can sometimes solve the problem entirely.
Other drugs that can contribute include medications for Parkinson’s disease, certain antidepressants, and erectile dysfunction drugs, particularly when combined with heart medications. Even over-the-counter sleep aids with sedating antihistamines can play a role. If your diastolic pressure started dropping around the same time you began a new medication, that timing is worth noting.
Why Low Diastolic Pressure Matters
A diastolic reading in the 70s is generally fine. The risk starts climbing below that. A large analysis tracking over 11,000 adults for three decades found that people with diastolic pressure between 60 and 69 mmHg were twice as likely to show subtle signs of heart damage compared to those with readings between 80 and 89 mmHg. Readings below 70 were also linked to higher rates of heart attack and hospitalization for heart failure.
A separate pooled analysis of over 31,000 people aged 55 and older found that diastolic pressures below 70 mmHg were associated with increased risk of dying from heart disease or any cause, compared to readings between 70 and 80 mmHg. The mechanism is straightforward: when diastolic pressure is low, the coronary arteries don’t fill as well between beats. If those arteries are already partially narrowed by plaque, the reduced flow can starve portions of the heart muscle of oxygen.
Increase Fluid and Salt Intake Strategically
For most health conditions, people are told to cut back on salt. Low diastolic pressure is one situation where the opposite may apply. Sodium helps your body retain water, which increases blood volume and supports pressure in the arteries. Adding an extra half teaspoon of salt per day through food, or drinking an electrolyte beverage, can make a measurable difference for people whose pressure runs low. Broth, pickles, olives, and salted nuts are easy ways to work this in.
Water intake matters too, though not quite the way most people assume. Drinking water does trigger a pressure-raising response, but research from the American Heart Association shows this isn’t because it expands blood volume. Plasma volume doesn’t actually increase after drinking water. Instead, the act of water hitting the stomach and intestines appears to activate nerve signals that tighten blood vessels. Regardless of the mechanism, staying consistently hydrated throughout the day, rather than drinking large amounts at once, helps maintain steadier pressure.
Exercise for Vascular Health
Exercise improves the tone and responsiveness of blood vessels over time, which helps your body regulate pressure more effectively. For people with chronically low diastolic pressure, the goal isn’t necessarily to raise the number through exercise alone but to improve the cardiovascular system’s ability to maintain adequate pressure during daily activities.
A meta-analysis in the Journal of the American Heart Association found that different types of exercise affect blood pressure differently. Dynamic resistance training (traditional weight lifting) and endurance exercise (walking, cycling, swimming) both influence vascular function. For someone with low diastolic pressure, moderate resistance training is particularly useful because it improves the muscular tone of blood vessel walls. Start gradually, especially if you’ve been sedentary, and be cautious with exercises that involve standing up quickly or holding your breath, both of which can cause sudden pressure drops.
Compression Garments
Compression stockings work by gently squeezing the veins in your legs, which pushes blood back toward your heart and prevents it from pooling in your lower body. This effectively increases the volume of blood available to your heart with each beat, supporting both systolic and diastolic pressure. Waist-high stockings rated at 20 to 30 mmHg or 30 to 40 mmHg of compression tend to be most effective. Knee-high stockings help less because a significant amount of blood pools in the thighs, not just the calves. Putting them on first thing in the morning, before blood has had a chance to settle into your legs, gets the best results.
Eat Smaller, More Frequent Meals
After a large meal, your body diverts a significant amount of blood to the digestive tract. For someone with already low diastolic pressure, this can cause a noticeable drop, especially within 30 to 60 minutes of eating. Smaller meals spread throughout the day reduce this effect. Cutting back on refined carbohydrates at meals also helps, since high-carb meals tend to cause larger post-meal pressure drops than meals built around protein, fat, and fiber.
Positional Adjustments
Simple changes in how you move through your day can reduce symptoms. Elevating the head of your bed by 4 to 6 inches (using blocks under the bedposts, not extra pillows) reduces the sudden pressure drop that happens when you stand up in the morning. Getting out of bed slowly, sitting on the edge for a minute before standing, and flexing your calf muscles before you rise all help your body adjust. Crossing your legs while standing or tensing your thigh muscles can provide a quick boost when you feel lightheaded.
When Medication Is Needed
If lifestyle changes aren’t enough, doctors can prescribe medications that raise blood pressure. The most commonly used option works by tightening blood vessels, which directly raises both systolic and diastolic pressure. It’s typically taken three times during the day, spaced about four hours apart, with the last dose no later than late afternoon to avoid raising pressure while you sleep. This type of medication is generally reserved for people whose symptoms significantly affect daily functioning, since it does come with side effects and requires monitoring.
Another approach uses a medication that helps the body retain sodium and water, expanding blood volume. This is sometimes used for people whose low pressure is related to adrenal insufficiency or autonomic nervous system dysfunction. Both options require careful dose adjustment, since the goal is to raise diastolic pressure into a healthier range without pushing systolic pressure too high.
Tracking Your Numbers
Home blood pressure monitors make it easy to spot patterns. Measure at the same times each day, ideally morning and evening, and record both numbers along with notes about what you ate, how much water you drank, and any symptoms. A diastolic reading that consistently sits below 60 mmHg deserves medical attention, especially if you’re over 50 or have any history of heart disease. Occasional dips into the low 60s without symptoms are less concerning. The pattern over weeks matters more than any single reading.