Preliminary research evaluating the effects of L-arginine, or simply arginine, on blood pressure looks promising for the future. More research is needed, but successful treatment of high blood pressure, or hypertension, could reduce the risk of subsequent health conditions, such as heart disease, atherosclerosis and stroke. Researchers use arginine in excess of the recommended allowance for its vasodilation properties - the ability to expand blood vessels.
L-arginine is an amino acid categorized as semi-essential, meaning that your body is able to produce it as long as you consume protein. People who do not consume the recommended range of protein, between 50 to 175 g, or have health conditions like burns, infections or sepsis, may need arginine supplementation. If you eat a variety of the daily recommended allowance for protein you are most likely not deficient in L-arginine. Healthy protein sources include lean meat, poultry, legumes, nuts, seeds, seafood and low-fat dairy products.
Scientists are predicting that because arginine converts into nitric oxide, a chemical compound that causes blood vessels to expand, it may be beneficial for treatment of vascular-related health conditions, such as high blood pressure, coronary artery disease, heart failure and blood vessel disease in the lower legs. Other therapeutic theories include arginine’s ability to initiate the production of protein in the body and may be useful for treating wounds and muscle-wasting disorders.
An early study, published in April 1998 in “Blood Pressure Monitoring,” evaluated arginine’s effect on high blood pressure in 30 men over age 51 with uncontrolled blood pressure. In addition to the men’s established hypertensive treatment, the participants were given intravenous arginine over a period of four days with regular monitoring of heart rate and blood pressure. The results showed that, while on the infusion treatment, blood pressures were lower. However the effect was limited to the treatment time only. Once the infusions were over, their blood pressure returned to previous levels. Long-term effects of infusion treatment are unknown.
High blood pressure during pregnancy is termed "preeclampsia." Published in the January 2005 issue of the “European Journal of Clinical Investigation,” was a study evaluating the effect of arginine on 61 hypertensive pregnant women. The women were given either oral arginine, or a placebo, for three weeks. The results showed that the women with the arginine experienced significantly lower blood pressure than those taking the placebo. The researchers suggest that arginine “may present a new, safe and efficient strategy” to lower high blood pressure in pregnant women.
Some side effects and adverse reactions have occurred from injections of arginine, including nausea, cramps, anaphylaxis, rash and shortness of breath. Arginine may also cause low blood pressure, electrolyte imbalances, increased risk of bleeding and increased blood sugar levels. Supplements and herbal products are not regulated by the U.S. Food and Drug Administration as strictly as prescription and over-the-counter drugs. Seek professional health care advice prior to using these products.