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.
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:
Upset stomach Heartburn Nausea Diarrhea Increased risk of bleeding
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.
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.
