Can L-arginine supplements lower blood pressure?
Answer From Francisco Lopez-Jimenez, M.D.
L-arginine (el-AHR-jih-nene) is an organic substance called an amino acid. Your body usually makes all the L-arginine it needs. You also get L-arginine through your diet in foods such as nuts, fish, red meat, soy, whole grains, beans and dairy products.
The body changes L-arginine to nitric oxide, a substance known to widen blood vessels. Some people take L-arginine supplements to relax and open arteries, which might help lower blood pressure. However, L-arginine supplements are rarely necessary and may only benefit people who have a true deficiency.
Research on L-arginine has had mixed results. The most recent research suggests that L-arginine may lower blood pressure, improve cholesterol and improve overall blood vessel health.
A review of several studies found that adults with high blood pressure who took daily L-arginine supplements lowered their bottom (diastolic) blood pressure number by about 2 to 3 millimeters of mercury (mm Hg).
When it comes to heart health, L-arginine may work better when combined with other vitamins, such as vitamins B6 and B12. However, larger, more-robust studies are needed to confirm these findings before experts can recommend everyday use of these supplements.
L-arginine drug interactions
It's important to know that L-arginine supplements can interact with some medications, including:
- Blood thinners, including aspirin and warfarin
- Certain diuretics
- Some high blood pressure medications
- Erectile dysfunction drugs
- Diabetes medications
Who shouldn't take L-arginine
Don't take L-arginine if you've had a heart attack. There are concerns that the supplement might increase the risk of death.
L-arginine supplements can worsen allergies and asthma. Use with caution.
Don't take L-arginine supplements if you've had cold sores or genital herpes. Too much L-arginine in your system can activate the virus that causes those conditions.
Talk to your doctor about supplements
A healthy diet and regular exercise are among the best ways to keep your blood pressure healthy. If you're thinking about taking an herbal or dietary supplement, such as L-arginine, talk to your doctor first. Some supplements can interact with blood pressure medications or make certain health conditions worse.
March 02, 2021
Francisco Lopez-Jimenez, M.D.
See more Expert Answers
- USDA National Nutrient Database for Standard Reference, Release 28. U.S. Department of Agriculture, Agricultural Research Service. http://ndb.nal.usda.gov. Accessed Jan. 25, 2021.
- Menzel D, et al. L‑arginine and B vitamins improve endothelial function in subjects with mild to moderate blood pressure elevation. European Journal of Nutrition. 2018; doi:10.1007/s00394-016-1342-6.
- L-arginine. Natural Medicines. https://naturalmedicines.therapeuticresearch.com. Accessed Jan. 25, 2021.
- Gambardella J, et al. Arginine and endothelial function. Biomedicines. 2020; doi:10.3390/biomedicines8080277.
- Zang H, et al. L-Arginine ameliorates high-fat diet-induced atherosclerosis by downregulating mir-221. Biomed Research International. 2020; doi: 10.1155/2020/4291327.
- L-arginine. Mayo Clinic. https://www.mayoclinic.org/drugs-supplements-l-arginine/art-20364681. Accessed Jan. 26, 2021.
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- Hadi M, et al. The effect of l-arginine supplementation on lipid profile: A systematic review and meta-analysis of randomised controlled trials. The British Journal of Nutrition. 2019; doi:10.1017/S0007114519001855.