Can Garlic Beat High Blood Pressure?

High blood pressure is also called hypertension. It affects about one in three adults in the United States.

Some people believe garlic can protect against high blood pressure. Proponents suggest increasing dietary intake of garlic or taking garlic extract as a supplement to treat or prevent high blood pressure.

This article looks at garlic and its use against high blood pressure. It also discusses whether the evidence really points to its effectiveness for this purpose.

Garlic Tablets
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How Garlic Is Thought to Help Blood Pressure

High blood pressure is a major risk factor for heart disease, the leading cause of death in the U.S. It can increase your risk of heart attack, and stroke and lead to major health issues like kidney damage and vision loss. It is also linked to memory impairment.

There is limited evidence garlic may be associated with a small reduction in blood pressure. It's thought that garlic may help lower blood pressure in part by stimulating the production of nitric oxide. This is a compound that helps relax and widen your blood vessels, which improves blood flow and reduces blood pressure.

What Research Says

The research into garlic and blood pressure is unfortunately very limited. Most studies are small and some are poorly designed. This makes it difficult for health officials to recommend garlic as a treatment for high blood pressure.

A 2015 review looked at nine studies with a total of 482 participants. The studies seemed to suggest that garlic supplementation reduced high blood pressure more effectively than a placebo. However, the authors found that if they looked only at the most well-designed studies, the benefits were reduced.

A 2013 Cochrane review looked at two trials involving 87 participants with hypertension. It concluded that there wasn't enough evidence to say whether garlic supplements could help reduce mortality in patients with high blood pressure.

Most studies that have found a benefit have looked at very high doses of a garlic supplement. Simply eating more garlic will not have any effect on your blood pressure.

Possible Side Effects

Garlic in food eaten in normal amounts is probably safe for most people. There is very little data about the safety of taking large amounts of garlic supplements, though. High doses may produce side effects such as:

Garlic supplements may also interfere with certain drugs and other supplements. People who are pregnant, nursing, or have a bleeding disorder shouldn't take garlic supplements.

Garlic may slow blood clotting. Garlic should not be taken with blood-thinning medications, including aspirin and warfarin, or certain supplements such as ginkgo. These combinations could raise your risk of adverse effects like bleeding and bruising.

Other Natural Alternatives

Lifestyle practices are crucial for controlling your blood pressure. These practices include:

  • Eating a balanced diet
  • Limiting your intake of sodium and alcohol
  • Achieving and/or maintaining a healthy weight
  • Exercising regularly
  • Avoiding smoking
  • Practicing stress-reduction

There's also some evidence that eating foods rich in omega-3 fatty acids and vitamin D may help reduce blood pressure.

Using Garlic to Lower Your Blood Pressure

Garlic is a good source of vitamin C and vitamin B6 and a healthy way to add flavor to your meals. Even though there is some evidence it may protect against high blood pressure, it should not be used as a substitute for standard medical care. At this time, the American College of Cardiology does not recommend garlic or any herbal medications as treatment for any cardiovascular disease.

Summary

There is limited evidence that large amounts of garlic supplements may reduce high blood pressure. Many of the studies that have looked into this, however, are small and not well-designed.

Garlic supplements may cause stomach problems and can interact with some medication. Don't take garlic supplements if you have a bleeding disorder or are taking blood-thinning medications.

Garlic can be a healthy part of your diet, but it should not be used as a substitute for medical care. If you have hypertension, talk to your healthcare provider about your treatment options.

Frequently Asked Questions

  • Does garlic lower blood pressure?

    The jury is out as to whether garlic can actually lower blood pressure. Some studies have shown high doses of garlic supplements can reduce blood pressure better than a placebo. However, a review of additional studies did not find sufficient evidence that garlic supplements can lower blood pressure enough to make a difference in a person’s risk of death from high blood pressure. 

  • Do garlic supplements cause heartburn?

    Yes, garlic supplements can cause gastrointestinal side effects including heartburn, upset stomach, nausea, and diarrhea. 

  • Can I take garlic supplements with blood thinners?

    No, garlic may slow blood clotting and should not be taken with blood-thinning medications as it can increase the risk of bleeding and bruising. This includes anticoagulants, such as heparin and warfarin, and antiplatelets including aspirin and clopidogrel. Certain supplements, like ginkgo, can also thin blood and should not be taken with garlic supplements. 

11 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Centers for Disease Control and Prevention. High blood pressure.

  2. Ried K, Frank OR, Stocks NP. Aged garlic extract reduces blood pressure in hypertensives: a dose-response trial. Eur J Clin Nutr. 2013;67(1):64-70. doi:10.1038/ejcn.2012.178

  3. American Heart Association. Health threats from high blood pressure.

  4. NIH Complementary and Integrative Health. Complementary health approaches for hypertension.

  5. Rohner A, Ried K, Sobenin IA, Bucher HC, Nordmann AJ. A systematic review and metaanalysis on the effects of garlic preparations on blood pressure in individuals with hypertension. Am J Hypertens. 2015;28(3):414-23.

  6. Qian X. Garlic for the prevention of cardiovascular morbidity and mortality in hypertensive patients: summaries of Nursing Care-Related Systematic Reviews from the Cochrane Library. Int J Evid Based Healthc. 2013;11(1):83. doi:10.1111/1744-1609.12008

  7. American Heart Association. Sorting folklore from fact on the health benefits of garlic.

  8. NIH National Center for Complementary and Integrative Health. Garlic.

  9. Michigan Medicine, University of Michigan. Garlic.

  10. Houston M. The role of nutrition and nutraceutical supplements in the treatment of hypertension. World J Cardiol. 2014;6(2):38-66. doi:10.4330/wjc.v6.i2.38

  11. Liperoti R, Vetrano DL, Bernabei R, Onder G. Herbal medications in cardiovascular medicine. J Am Coll Cardiol. 2017;69(9):1188-99.

Additional Reading
Cathy Wong

By Cathy Wong
Cathy Wong is a nutritionist and wellness expert. Her work is regularly featured in media such as First For Women, Woman's World, and Natural Health.