Clinical data suggest that curcumin may have anti-inflammatory and anticancer effects, which has renewed scientific interest in its potential for helping to prevent and treat a number of diseases. Elevation of arterial blood pressure, hypertension, leads to shortened life expectancy because of the impending cardiovascular disease often associated with this condition. Dietary curcumin has been shown to improve blood pressure control and decrease the risk of associated complications. You should consult a physician before treating hypertension with herbal supplements, however.
Biologically Active Compounds Found in Turmeric
Turmeric is a perennial plant of the ginger family, Zingiberaceae, indigenous to southern Asia. The rhizomes are boiled, dried and ground into a powder commonly used as a spice, for dyeing fabrics and for medicinal benefits. The latter are reportedly due to its biologically active ingredient, curcumin. Research is increasing on the effects of curcumin and turmeric in a variety of clinical disorders, such as combating cancer, heart disease and hypertension.
Hypertension and Cardiovascular Disease
Hypertension, or high blood pressure, is a persistent medical condition characterized by elevated systemic arterial blood pressure, and classified as either primary (essential) or secondary. The majority of cases are termed "primary hypertension," referring to high blood pressure for which no clear medical cause can be found and usually attributed to diet, body mass and lifestyle choices. Secondary hypertension is caused by factors affecting the heart, kidneys, vascular system, or endocrine system. Persistent hypertension is one of the risk factors for stroke, heart failure and arterial aneurysm, and is a leading cause of chronic kidney failure and premature death.
Curcumin Treatment of Hypertension
The August 2006 edition of the "Chinese Journal of Applied Physiology" published a study investigating the effect of curcumin on pulmonary arterial pressure, PAP, and formation of collagen, necessary for vessel wall formation, in clinically induced hypertensive rats. The test animals were divided into three groups: a normal control group, a hypertensive group receiving no treatment and a hypertensive group fed a diet supplemented with curcumin. The findings showed that the PAP in the hypertensive group receiving no treatment remained significantly higher than that in the other groups. Additionally, microscopic examination showed the density of smooth muscle cells and thickness of pulmonary arteries were also significantly greater in the untreated hypertensive group. The authors concluded that curcumin can decrease pulmonary arterial pressure, improve pulmonary vessel elasticity and inhibit the deposition of collagen in pulmonary arterioles.
In an article appearing in the May 2009 issue of the "American Journal of Physiology," researchers investigated the efficacy of curcumin as a possible treatment for chronic renal failure, CRF, in clinically induced hypertensive rats. The effectiveness of curcumin was compared with enalapril, a pharmaceutical known to alleviate CRF. The study animals were divided into three groups: untreated, curcumin-treated, and enalapril-treated. The study showed that renal dysfunction was significantly reduced by curcumin and enalapril treatment; however, only enalapril treatment significantly improved blood pressure, with only slight improvement in the curcumin-treated group. Anti-inflammatory responses were also improved by curcumin and enalapril. The authors concluded that the anti-inflammatory property of curcumin may be responsible for alleviating CRF.
Contradictory Study on Benefits of Curcumin Treatment
An October 2008 study published in "Acta Medica Indonesia" investigated the effect of curcumin on lipid levels, a known indicator of hypertension, in patients with acute coronary artery disease. The study was designed to evaluate the effects of curcumin on total cholesterol, low-density lipoproteins, LDL, high-density lipoproteins, HDL, and triglycerides. Patients were recruited for a randomized and controlled trial, divided into four groups and treated with several dosages of curcumin. The effects of curcumin on total and LDL cholesterol levels showed a trend: the lower dose of curcumin, the greater the reduction in LDL. For HDL, the lower the dose of curcumin, the more levels increased. However, for triglycerides, the pattern was dissimilar: the group receiving a moderate dose of curcumin showed the least increase, followed by the low-dose group and finally the group receiving high doses of curcumin. The results of the study were inconclusive, as there was not a clear correlation of lowering arterial blood pressure and curcumin consumption.
References
- "Acta Medica Indonesia"; The Effect of Curcumin on Lipid Level in Patients with Acute Coronary Syndrome; I. Alwi et al.; October 2008
- "American Journal of Physiology. Renal Physiology"; Curcumin Ameliorates Renal Failure in 5/6 Nephrectomized Rats: Role of Inflammation; S. Ghosh et al.; May 2009
- "Chinese Journal of Applied Physiology"; Effect of Curcumin on Pulmonary Hypertension and Wall Collagen of Pulmonary Arterioles of Chronic Hypoxic Hypercapnic rats; Q. Lin et al.; August 2006
