Methods
A list of potential natural antihypertensive agents was initially identified. This list was generated by a review of those agents included in The Review of Natural Products[7] and the Natural Medicines Comprehensive Database[3] as having potential benefits in hypertension. These were utilized because of their widespread acceptance as reputable and accurate sources of information regarding the study of natural products. The following agents were identified: coenzyme Q10 (CoQ10), ubiquinone, garlic, arginine, fish oil, hawthorn, olive oil, vitamin C, vitamin E, skullcap, barberry, betel nut, bishop's weed, bitter melon, cat's claw, celery, Eleutherococcus, gotu kola, guar gum, herbal diuretics, hibiscus, holly, jiaogulan, procaine, lemongrass, mistletoe, morinda, Nigella sativa, oil of evening primrose, passion flower, periwinkle, reishi mushroom, rhubarb, saffron, stevia, veratrum, white hellebore, willard water, withania, yellow root, yohimbine, and yucca. A Medline search of the published literature was then conducted using each identified agent. The following additional search terms were also used: "hypertension," "alternative medicine," and "dietary supplement." The searches were limited using the parameters 1999-2003, human, and English language (this may be a limitation of the study).
Many sources claim that specific alternative therapies or supplements are efficacious in the treatment of hypertension; however, the degree of antihypertensive efficacy is rarely impressive when compared with the blood pressure reduction that can be documented with the incorporation of lifestyle modifications. For example, in the Dietary Approaches to Stop Hypertension (DASH) trial it was noted that the DASH combination diet significantly (p < 0.05) lowered both systolic blood pressure (SBP) and diastolic blood pressure (DBP), with an overall decrease in SBP of 11.4 mm Hg and DBP of 5.5 mm Hg in hypertensive individuals.[8] The DASH combination diet is rich in fruits, vegetables, and low-fat dairy products.
Weight loss and sodium reduction have also been shown to decrease blood pressure. The phase II Trials of Hypertension Prevention[9] observed that a weight loss of 4.3-4.5 kg along with a concomitant decrease in sodium excretion of 50 mmol/d was associated with an SBP decrease of 4.0 mm Hg and a DBP decrease of 2.8 mm Hg at 6 months.
A more recent randomized, controlled trial assessed the efficacy of simultaneously implementing diet, exercise, and weight loss.[10] Forty-four hypertensive, overweight adults, taking a single blood pressure medication, were randomized to one of two groups. The lifestyle group ate a low-calorie, low-sodium diet based on the DASH diet and participated in moderate intensity exercise three times weekly. The control group continued their previous lifestyle. The lifestyle group lost an average of 4.9 kg in 9 weeks. Reductions in daytime blood pressure readings were 12.1 mm Hg systolic and 6.6 mm Hg diastolic.[10]
Based on the average reduction of blood pressure noted in those trials, dietary supplements are defined as possessing some evidence of benefit when an SBP reduction of 9.0 mm Hg or greater and/or a DBP reduction of 5.0 mm Hg or greater can be documented. The cut-off limits are based on a simple average of the blood pressure reduction noted in the three trials just discussed. Dietary supplements with little or no evidence of benefit are those that either have little or no literature to support efficacy or those that prove to decrease SBP by less than 9.0 mm Hg and/or decrease DBP by less than 5.0 mm Hg. According to these parameters, five agents meet the criterion of some evidence of benefit in the treatment of hypertension, while the other agents noted have little or no evidence of benefit to promote efficacy. The agents with some evidence of benefit include CoQ10, fish oil, garlic, vitamin C, and L-arginine ( Table 1 ).
© 2004 Le Jacq Communications, Inc.
Cite this: The Natural Treatment of Hypertension - Medscape - May 01, 2004.
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