Low blood pressure, defined as a reading below 90/60 mmHg, can cause dizziness, fatigue, and fainting. The most effective immediate strategy is drinking water: consuming about 16 ounces (480 mL) can raise systolic blood pressure by 11 mmHg in healthy older adults and even more in people with autonomic disorders. Beyond water, a combination of dietary changes, physical techniques, and lifestyle adjustments can bring your numbers up reliably.
Drink More Water, and Drink It Strategically
Water is the simplest and most effective way to raise blood pressure without medication. A study published in Circulation found that drinking 480 mL (roughly two cups) of water raised seated blood pressure by 11 mmHg in older adults and by 43 mmHg in patients with autonomic failure. Drinking half that amount produced a smaller effect, so volume matters. The blood pressure rise typically begins within minutes and doesn’t depend on changes in blood volume. Instead, it appears to trigger a reflex through the nervous system.
A review in Neurology comparing nonpharmacologic treatments for orthostatic hypotension concluded that bolus water drinking should be the standard first-line approach. If you tend to feel lightheaded when standing, drinking a full glass of water 5 to 10 minutes beforehand can help.
Increase Your Salt Intake
Salt helps your body retain fluid, which expands blood volume and raises pressure. For people with chronically low blood pressure, a daily intake of at least 6 grams of salt is sometimes recommended. That’s roughly a teaspoon, which is more than the standard dietary guidelines suggest for the general population. This approach only makes sense if your blood pressure is genuinely low, not if you’re in the normal range.
Good sources of salt include soy sauce, canned soups, deli meats, and processed foods. However, relying heavily on processed foods for sodium comes with downsides like excess sugar and low nutritional quality. Salt tablets are a more controlled alternative and let you increase sodium without overhauling your diet.
Use Physical Maneuvers for Quick Relief
When you feel a dizzy spell coming on, certain body movements can raise your blood pressure within seconds. These work by squeezing your muscles around blood vessels, physically pushing blood back toward your heart and brain. A meta-analysis in Frontiers in Cardiovascular Medicine found that these maneuvers raised standing systolic blood pressure by an average of about 15 mmHg.
The most effective options include:
- Leg crossing with tensing: Cross your legs at the ankles while standing and squeeze your thigh and calf muscles. This is practical enough to do anywhere without drawing attention.
- Squatting: Produces a large cardiovascular response and can abort symptoms quickly. The downside is that blood pressure often drops again when you stand back up.
- The crash position: Squatting with your head between your knees. This combines the benefits of squatting with gravity helping blood reach your brain.
- Hand gripping: Clench both fists hard and hold. This creates enough muscle tension to raise pressure temporarily.
- Calf raises and marching in place: Rhythmic leg movements activate the muscle pump in your calves, pushing pooled blood upward.
These are temporary fixes. They work while you’re doing them and for a short window afterward. But they’re invaluable for getting through a moment of dizziness or preventing a faint.
Eat Smaller, More Frequent Meals
Blood pressure naturally dips after eating because your body diverts blood flow to the digestive system. For people prone to low blood pressure, large meals can cause a noticeable drop, sometimes enough to cause lightheadedness or fainting. This is called postprandial hypotension, and it’s especially common in older adults.
Switching from three large meals to six smaller ones reduces the severity of this drop. In patients with autonomic failure, six small meals produced blood pressure drops of only 11 to 20 mmHg compared to much larger decreases with three standard meals. The mechanism is straightforward: a moderately full stomach activates the sympathetic nervous system (increasing blood pressure), while a stomach that empties rapidly sends digested food to the small intestine too quickly, triggering a pressure drop.
Carbohydrate-heavy meals tend to worsen the problem because carbohydrate digestion speeds up stomach emptying. Meals with more protein and fat slow things down. If you notice you feel worst after pasta, bread, or sugary meals, shifting toward protein-rich foods at each sitting can help.
Have Caffeine Before It Matters
Caffeine reliably raises blood pressure by 3 to 15 mmHg systolic and 4 to 13 mmHg diastolic. The effect kicks in within 30 minutes, peaks at 1 to 2 hours, and can last more than 4 hours. A cup of coffee or tea before activities where you’ll be standing for a long time, or first thing in the morning when blood pressure tends to be lowest, can provide a meaningful boost.
Regular caffeine consumers may develop some tolerance to this effect, but it doesn’t disappear entirely. Timing matters more than quantity. A single cup of coffee before you need to be on your feet is more useful than sipping throughout the day.
Limit Alcohol
Alcohol lowers blood pressure through multiple pathways. It increases production of nitric oxide, a potent vasodilator, while simultaneously reducing a signaling molecule that constricts blood vessels. Its metabolic byproduct, acetaldehyde, is also a vasodilator. The combined effect can lower blood pressure for roughly 12 hours after drinking. If your blood pressure is already low, even moderate alcohol consumption can push you into symptomatic territory. Cutting back or avoiding alcohol, particularly before situations where you’ll be standing or active, is one of the simplest protective steps.
Elevate Your Head While Sleeping
Sleeping with your head raised by about 10 degrees (roughly a 9-inch elevation at the head of the bed) can improve your blood pressure tolerance when you get up in the morning. This works by preventing your body from fully redistributing fluid while you sleep, so the shift when you stand is less dramatic. You can achieve this with bed risers under the headboard posts or a foam wedge under the mattress. Stacking pillows is less effective because it bends your neck rather than tilting your whole body.
When Lifestyle Changes Aren’t Enough
If dietary and behavioral changes don’t resolve your symptoms, prescription medications can help. The two most commonly used work through different mechanisms. One helps your body retain sodium and water, expanding your blood volume. The other directly tightens blood vessels. Both are taken by mouth, and your doctor will typically start at a low dose and adjust based on your response. These medications are generally reserved for people whose low blood pressure causes frequent symptoms like fainting, severe dizziness, or falls, rather than those who simply have readings on the low side without complaints.
Compression garments are sometimes suggested, but the evidence is less encouraging. Thigh-high stockings at 23 to 32 mmHg of pressure raised standing systolic blood pressure by only about 6 mmHg in studies of older adults, and a Neurology review described them as the least effective nonpharmacologic option. If you find them comfortable and they seem to help, there’s no harm in wearing them. But they shouldn’t be your primary strategy.