James Odell, OMD, ND, L.Ac.
Hypertension is one of the most prevalent and important health problems facing society today. In general, an individual’s “blood pressure,” or systemic arterial pressure, refers to the pressure measured within large arteries in the systemic circulation. This number splits into systolic blood pressure and diastolic blood pressure. Blood pressure is traditionally measured using auscultation with a mercury-tube sphygmomanometer. It is measured in millimeters of mercury and expressed in terms of systolic pressure over diastolic pressure. Systolic pressure refers to the maximum pressure within the large arteries when the heart muscle contracts to propel blood through the body. Diastolic pressure describes the lowest pressure within the large arteries during heart muscle relaxation between beating.
Arterial pressure directly corresponds to cardiac output, arterial elasticity, and peripheral vascular resistance. Blood pressure is remarkably easy to alter and can be affected by many activities. Thus, blood pressure is the force that a person's blood exerts against the walls of their blood vessels. This pressure depends on the resistance of the blood vessels and how hard the heart must work. In 90% of cases the etiology (cause) of hypertension is considered ‘unknown’. This is called ‘essential hypertension’. In truth, there are many clear reasons that blood pressure may become elevated and uncovering those reasons is paramount to controlling hypertension.
Within the last few years, the guidelines of what is considered normal blood pressure has changed. Currently, ‘normal’ blood pressure is now defined as under 120/80, whereas before, normal was under 140/90. This change has resulted in thousands, if not millions, of people being classified as having hypertension and placed on antihypertensive medications. Of course, this change has been an economic boost to the pharmaceutical industry.
Conventional pharmaceutical oriented medicine rarely investigates the causes of hypertension. If it is high, you go on medication. In conventional medicine high blood pressure is treated with diuretics, adrenergic receptor blockers, calcium channel blockers and angiotensin converting enzyme inhibitors. Of course, these pharmaceutical agents carry side effects as they dysregulate numerous enzyme systems. Side effects include vertigo, fatigue, depression, congestive heart failure, hallucinations, tachycardia, angina, hypokalemia, gastrointestinal disturbances and leukopenia. Generally, side effects occur more in older patients than in younger patients.
High blood pressure typically does not cause symptoms. Long-term high blood pressure, however, is a risk factor for coronary artery disease, stroke, heart failure, atrial fibrillation, peripheral arterial disease, vision loss, chronic kidney disease, and even dementia. If left untreated hypertension is a progressive and potentially fatal disease.
Non-pharmacological treatments such as diet, exercise, relaxation (meditation) and yoga are effective for controlling mild to moderate hypertension. Diet and lifestyle changes are powerful medicine. Even if your blood pressure is normal now, you can help to prevent it from becoming elevated starting today. Many mechanisms have been proposed to account for the rise in peripheral resistance in hypertension. Evidence implicates disturbances in the kidneys' electrolyte and water management as a potential cause. In other words, dehydration and deficiencies in magnesium and potassium can potentiate hypertension. Improving oxygenation to the cells is also an effective strategy. One of the best supplements for this is Coenzyme Q10.
In treatment of mild to moderate hypertension, bioregulatory strategies are to offer adequate hydration, supplements with electrolytes (magnesium and potassium), CoQ10, reduce sugar/ processed carbohydrates and excess salt, utilize regular exercise and meditation. Most people benefit from exercise at least 5 days of the week. Examples of suitable activities are walking, cycling, swimming, yoga and Pilates. Smoking can increase blood pressure too. Avoiding or quitting smoking reduces the risk of hypertension, serious heart conditions, and other health issues.
There are several lab tests that should be considered for all high blood pressure patients. Lipid panels are always ordered for routine testing; however, rarely is lipoprotein(a) tested. Studies have identified Lp(a) as a risk factor for cardiovascular disease. In addition, some chronic inflammatory markers associated with overall heart health are ferritin, fibrinogen, and c-reactive protein (HS) also called cardio CRP. Homocysteine is used to assess methylation function associated with vascular disease.
In this article hibiscus tea is discussed as an aid in controlling hypertension without side effects.
Dried Hibiscus Flowers
There are numerous herbs and herbal formulations that also assist with regulation of circulation and balance of blood pressure. One herb proven to reduce hypertension is Hibiscus sabdariffa L. Hibiscus has a long history of medicinal use. In cultures all over the world, the vibrant flower is used to treat a variety of ailments and illnesses. The most popular species of hibiscus used in medicine is Hibiscus sabdariffa, also known as Roselle.
Hibiscus is widely grown in Central and West Africa, South East Asia, and elsewhere throughout the globe. Drinking a tea made from the plant is the most common way to use hibiscus medicinally. The thick, red and fleshy, cup-shaped calyces of the flower are consumed worldwide as a cold beverage and as a hot drink. The tea is made from drying many different parts of the plant, but mostly the flower itself. Once the dried parts are steeped, the tea turns a rich ruby red color. The drink itself is quite sour, with a taste like cranberries.
Hibiscus tea has been used traditionally for many conditions, particularly high blood pressure, liver disorders, high cholesterol and infections.1, 2, 3, 4, 5 Research demonstrates that the hot (or cold) Hibiscus beverage is full of vitamin C and antioxidants, so it is a great way to prevent colds during the winter months.6, 7, 8, 9, 10, 11
A 2010 study published in the Journal of Nutrition found that consuming hibiscus tea lowered blood pressure in people at risk of high blood pressure and those with mildly high blood pressure.12 Study participants consumed three 8-ounce servings of hibiscus tea or a placebo beverage daily for 6 weeks. Those who drank the hibiscus tea saw a significant reduction in their systolic blood pressure, compared to those who consumed the placebo drink. The researchers concluded, “These results suggest daily consumption of hibiscus tea, in an amount readily incorporated into the diet, lowers BP in pre- and mildly hypertensive adults and may prove an effective component of the dietary changes recommended for people with these conditions.”
Numerous other studies have also demonstrated the anti-hypertensive effects of Hibiscus sabdariffa L. in both humans and experimental animals. Recent pharmacological studies have shown that Hibiscus sabdariffa extracts significantly reduced blood pressure in humans13, 14, 15, 16, 17, 18 and in experimental animals 19, 20, 21, 22. However, the exact mechanisms responsible for these effects of Hibiscus sabdariffa are not fully understood.
Safety and Toxicology
From animal studies it has been shown that Hibiscus sabdariffa is a very safe plant to
consume. Its extracts are characterized by a very low degree of toxicity.23, 24, 25
Making Hibiscus Tea
Desired Ingredients:
2 cups fresh organic Hibiscus Flowers (or 1/2 cup dried organic Hibiscus Flowers)
8 cups spring water
(optional) 1/8 cup raw honey (add more if you like your tea sweeter)
(optional) 3 tablespoons fresh lime juice
Bring the hibiscus flowers and water to a boil in a large pot. Once the water starts
boiling, switch off the flame and cover the vessel. At this point, you can also add
other herbs if desired, such as lemon grass or lemon balm. Let the tea steep for 15-
20 minutes. Mix in the honey and lime juice till completely combined. Strain the
tea. Serve hot or cold.
Dosage
Generally, it is not necessary to exceed a quart a day of hibiscus tea for adults and a halfquart for a 75-pound child.
References
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Press, Totowa, NJ, 2003.
2. Wang, Chau-Jong, Jin-Ming Wang, Wea-Lung Lin, Chia-Yih Chu, Fen-Pi Chou, and TsuiHwa Tseng. "Protective effect of Hibiscus anthocyanins against tert-butyl hydroperoxideinduced hepatic toxicity in rats." Food and chemical toxicology 38, no. 5 (2000): 411-416.
3. Liu, Jer-Yuh, Chang-Che Chen, Wen-Hong Wang, Jeng-Dong Hsu, Mon-Yuan Yang, and
Chau-Jong Wang. "The protective effects of Hibiscus sabdariffa extract on CCl4-induced
liver fibrosis in rats." Food and Chemical Toxicology 44, no. 3 (2006): 336-343.
4. Lin, Tzu-Li, Hui-Hsuan Lin, Chang-Che Chen, Ming-Cheng Lin, Ming-Chih Chou, and
Chau-Jong Wang. "Hibiscus sabdariffa extract reduces serum cholesterol in men and
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(1991): 567-576.
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"Anthocyanin and antioxidant capacity in Roselle (Hibiscus sabdariffa L.) extract." Food
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