11 Supplements That May Lower Blood Pressure

High blood pressure (hypertension) can lead to serious complications like heart attack and stroke if not controlled. Continued management is needed to avoid such complications.

Managing blood pressure often involves medication and lifestyle changes. Supplements can also help lower blood pressure. Here are common supplements that may lower blood pressure.

1. Potassium

Too much sodium can raise blood pressure. Researchers believe potassium can reduce this effect because the more potassium you eat, the more sodium you wash away with urine.

Potassium can also help lower blood pressure by easing the tension in your blood vessel walls. The American Heart Association (AHA) and the World Health Organization (WHO) recommend increasing potassium intake to lower blood pressure.

The recommended daily potassium intake is about 3,400 milligrams for men and 2,600 milligrams for women. The AHA recommends having 3,500-5,000 milligrams of potassium daily to prevent or lower high blood pressure with potassium.

A potassium supplement can help you reach this recommended daily dose. You can also get potassium through dietary sources like bananas, apricots, and tempeh.

Potassium supplements are generally safe, but you may experience side effects like stomach pain, diarrhea, and vomiting. If you experience symptoms like mental confusion, leg heaviness, stomach pain, unusual bloating, or black stool after taking potassium supplements, call your healthcare provider immediately.

Potassium may also interact with blood pressure-lowering medications like Qbrelis (lisinopril), Cozaar (losartan), Lasix (furosemide), and Midamor (amiloride). Before taking potassium supplements, inform your healthcare provider about any other medications or supplements you take. 

2. Magnesium

Studies have found magnesium supplements can help lower blood pressure and prevent hypertension.

One analysis of 11 trials found a significant reduction in blood pressure among people who received magnesium supplements. Specifically, systolic blood pressure (the first number in a blood pressure reading) decreased by about 4.18 millimeters of mercury (mm Hg), and diastolic blood pressure (the second number) decreased by 2.27 mm Hg.

Some research shows magnesium may only be effective for lowering blood pressure in people with a magnesium deficiency. 

Magnesium has been successfully used in clinical trials at 365-450 milligrams daily. However, the maximum recommended dose from supplements or medications for people 9 years or older is 350 milligrams. Taking more than this may lead to side effects like diarrhea, stomach cramps, nausea, and, in cases of very high doses, irregular heartbeats.

You can also increase your magnesium intake from foods like spinach, almonds, and edamame.

3. Garlic

Garlic extract has been found to lower blood pressure in people with uncontrolled hypertension, either when used alone or with blood pressure-lowering medications.

Analyses of multiple studies have found that garlic supplements significantly reduced systolic blood pressure by 8-9 mm Hg and diastolic blood pressure by 5.5-7 mm Hg among people with hypertension.

The amount of garlic extract used in studies to lower blood pressure ranged from 480-1,200 milligrams.  

Garlic extract is generally safe and tolerable. However, you may experience side effects like hot flashes, burping, gas, bloating, and dizziness.

Taking garlic supplements may also increase your risk of bleeding, which can worsen if you use blood thinners like warfarin (sold under brand names like Jantoven and Coumadin). Talk to your healthcare provider if you are planning to use garlic supplements with blood thinners.

4. Vitamin D

Research has shown that low vitamin D levels may increase hypertension risk. Therefore, vitamin D supplementation may help reduce or prevent the development of hypertension.

One study found that vitamin D supplements lower blood pressure in people with vitamin D deficiency who are over 50 years old and have obesity. Other research has found that long-term vitamin D supplementation may reduce the risk of developing hypertension, especially among those with vitamin D deficiency. However, using vitamin D supplements to lower blood pressure may not benefit people without a deficiency.

The dosage of vitamin D used to reduce blood pressure varied across studies, but most participants received between 800 and 2,000 international units (20 and 50 micrograms) daily.

While generally well-tolerated, potential vitamin D side effects include nausea and constipation. Vitamin D may also interact with certain medications like orlistat (a weight loss drug sold under brand names like Alli and Xenical), statins, steroids, and thiazide diuretics like Hygroton (chlorthalidone).

Vitamin D can also be obtained through sun exposure and certain foods, such as trout, salmon, and tuna.

5. CoQ10

Coenzyme Q10 (CoQ10) is a natural enzyme that helps the body convert food to energy. Although the body makes CoQ10 naturally, it can also be obtained through food—such as meats, dairy, eggs, and legumes—and dietary supplements.

Research has shown that CoQ10 supplements may help reduce blood pressure, especially in people with diabetes and dyslipidemia (abnormal lipid levels). One study observed that using about 100-200 milligrams of CoQ10 supplements daily gave the greatest benefit in blood pressure reduction. However, other studies have found mixed results on the benefits of CoQ10 in reducing blood pressure.

CoQ10 is generally well tolerated up to 1,200 milligrams daily. Some people may experience side effects like insomnia with doses over 100 milligrams daily. Other rare adverse effects of CoQ10 supplements include dizziness, light sensitivity, headache, heartburn, fatigue, and increased involuntary movements.

CoQ10 may interact with some medications like warfarin. It should also be used with caution in people with diabetes, especially those prone to episodes of low blood sugar, as the supplement can lower blood sugar in some people.

6. Green Tea

Tea consumption, especially green tea, has been found to reduce the risk of high blood pressure by about 10%.

One review found that green tea reduced systolic blood pressure by 1.98 mm Hg and diastolic blood pressure by 1.92 mm Hg. Other research has shown more mixed results, with some results showing green tea only significantly reducing systolic blood pressure, not diastolic.

Research shows that the benefit of green tea on blood pressure reduction was greater with a longer tea intake (three or months).

The doses of green tea used in clinical studies varied from 208-1,344 milligrams daily. However, studies found that low-dose green tea was often more effective in reducing blood pressure.

Green tea is generally safe. However, consuming about 400-4,000 milligrams of catechin (the active ingredient in green tea) daily can cause stomach pain, nausea, and discomfort.

Although uncommon, green tea has been associated with liver problems, especially for those who use green tea extracts in pill form. Consult your doctor if you have liver problems before using green tea supplements. 

7. Calcium

Calcium supplements can help lower blood pressure However, evidence appears stronger in people 35 or older and only moderate for younger people. People who are pregnant may also benefit more. The WHO recommends daily calcium supplements (1.5–2 grams of oral elemental calcium) for pregnant people with low dietary calcium intake to reduce the risk of preeclampsia (high blood pressure that occurs during pregnancy).

Most studies that have used calcium to reduce blood pressure have used it in doses of 1,500 milligrams or higher. Research has shown that the higher the calcium dose, the greater the drop in blood pressure. However, it’s recommended that daily calcium intake stay below 2,000 milligrams as higher doses increase the risk of adverse effects.

Calcium supplements, especially those containing calcium carbonates, may cause constipation, gas, bloating, stomach pain, and, in severe cases, kidney stones.

Calcium may also interact with certain medications, such as Tivicay (dolutegravir), antibiotics, lithium, and levothyroxine (a thyroid hormone sold under brand names like Synthroid and Levoxyl). If you take any of these medications, it’s important to maintain a significant time gap between calcium intake and medication use. Consult with a pharmacist for specific recommendations.

You can also get calcium from your diet by increasing your intake of milk, yogurt, cheese, and vegetables such as broccoli and kale.

8. Omega-3

There is moderate evidence to suggest that omega-3 supplements—particularly docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA)—can help lower blood pressure.

One analysis of data on 5,000 participants aged 22-86 found that adults who consumed 2-3 grams of combined EPA and DHA omega-3 fatty acids experienced an average reduction in blood pressure of 2 mm Hg compared to those who did not consume the fatty acids.

It appears that 3 grams of daily omega-3 fatty acid consumed in foods or supplements is the optimal dose to help lower blood pressure.

Omega-3 fatty acids are generally considered safe. However, it’s recommended that the daily intake of EPA and DHA combined not exceed 3 grams from food and 2 grams from supplements. High doses may reduce immunity and cause bleeding problems. Other side effects include diarrhea, nausea, stomach pain, and fatigue. 

Some food sources of omega-3 include fish, flax seeds, chia seeds, walnuts, and canola oil.

9. Beetroot

Beetroot, or simply beet, has been extensively studied for its potential benefits in reducing high blood pressure. The vegetable is rich in substances like nitrate, betaine, anthocyanins, and flavonoids, which help lower blood pressure. 

Beetroot can be consumed in different forms, including as a powder or juice supplement.

In one analysis involving 218 participants, people who consumed approximately 70-250 milliliters of beetroot juice experienced a significant reduction in systolic blood pressure. However, the effect on diastolic blood pressure was less pronounced.

Research suggests beetroot may lower blood pressure more effectively in people with underlying health conditions like obesity than in otherwise healthy people.

10. Melatonin 

Melatonin is a hormone your brain makes. It regulates the sleep-wake cycle. 

Research suggests that melatonin may also help lower blood pressure. However, the magnitude of its blood pressure-lowering effects varies among studies. Plus, only controlled-released melatonin appears to reduce blood pressure. Immediate-release melatonin did not have that effect.

In one study, controlled-release melatonin reduced systolic blood pressure by approximately 3.6 mm Hg. However, the effect was not statistically significant for diastolic blood pressure.

Melatonin supplements appear safe for short-term use, but there is not enough information on their safety in the long term. Potential side effects include drowsiness, nausea, and headaches. 

Melatonin may also slow down the blood clotting process, increasing the risk of bleeding. It is best to avoid combining it with other supplements known to have blood-thinning properties, such as ginger, garlic, ginkgo, or ginseng.

11. L-Arginine

L-arginine is an amino acid converted in the body to nitric oxide, a potent chemical that helps widen the blood vessels.

Due to its effect on widening or relaxing blood vessels, L-arginine has been studied as a potential blood pressure-lowering agent. Research shows that L-arginine helps reduce both systolic and diastolic blood pressure in adults with hypertension. The effect may be greater in females than in males. 

L-arginine has also been shown to lower blood pressure in pregnant women with preeclampsia. However, in these cases, a healthcare provider usually gives the L-arginine through a vein. It is unclear whether oral L-arginine has any effect on blood pressure in preeclampsia. 

L-arginine may be safe when taken short-term. Adults have used oral L-arginine safely in doses between 1.5-24 grams daily for up to 18 months. Long-term use of L-arginine may accelerate the decline of kidney function and should be avoided, especially by older adults. Potential side effects of L-arginine include stomach pain, diarrhea, and bloating.

L-arginine can also be obtained from dietary sources like meat, fish, dairy products, and nuts.

Other Tips for Lowering Blood Pressure

Hypertension has no cure, so managing blood pressure is a lifelong commitment. In addition to medication, incorporating certain lifestyle changes can help lower blood pressure. You could: 

• Manage your weight
• Exercise regularly
• Reduce sodium intake
• Limit alcohol consumption
• Get quality sleep
  

When To See a Healthcare Provider

Most people with hypertension do not experience any symptoms. It’s important for adults to check their blood pressure regularly, even if they feel fine. 

If your blood pressure is 180/120 or greater, wait a minute or two and then retake your reading. If the second reading is just as high, contact a healthcare provider about what to do. These readings could indicate hypertensive urgency. 

If you have very high blood pressure and symptoms like severe headache, chest pain, blurred vision, nosebleed, difficulty breathing, and buzzing in the ears, see a healthcare provider immediately. This could be a sign of a hypertensive emergency.

You should also see a healthcare provider if you experience any concerning symptoms when taking a supplement.

A Quick Review

High blood pressure can be a serious health problem, especially if left untreated. Supplements like potassium, calcium, magnesium, vitamin D, garlic, and omega-3 fatty acids may help lower blood pressure.

If you have high blood pressure, your provider might recommend taking supplements as part of your management. They may also prescribe medication and lifestyle changes like reducing sodium intake, exercising regularly, and losing weight.