Fluid through a pipe: natural management of hypertension.Hypertension--Symptom or Diagnosis?
When a patient presents in my office with high blood pressure, I return to the teachings of my mentors in naturopathic medical school. My teachers consistently stressed the difference between a symptom and a diagnosis. For example, when a patient comes into the office with fatigue, they are coming to me with a symptom--a symptom that, for 10 different patients, can have 10 different causes. What should follow a complete work-up to determine diagnosis. One patient with fatigue may have cancer, another may have iron deficiency anemia, and another may have a low-functioning thyroid.
Hypertension (HTN) is the same; it is not a disease that immediately gets treated with a drug. HTN is a symptom, and for those 10 hypertensive patients, we may have 10 different causes. My goal is to determine the cause and address it.
What Is Hypertension?
Hypertension, or high blood pressure, is defined as elevated pressure in the arteries of the body. Taking a blood pressure is done by measuring the highest (systolic) and lowest (diastolic) pressure in an artery during a cardiac cycle--and corresponds with the contracting and relaxing of the heart muscle. High blood pressure is diagnosed if it is consistently at or above 140/90 mmHa.
A higher than normal blood pressure can cause major damage to the body. The higher shearing force of red blood cells against a vessel wall can accelerate atherosclerosis, rupture a blood vessel in the brain leading to stroke, and damage the tiny capillary beds of the kidney, leading to lowered kidney function.
Fluid through a Pipe
The simplest way to find the underlying causes of hypertension is to review the three factors that increase the resistance of a fluid through a pipe:
1. increased viscosity of the fluid
2. decreased diameter of the pipe
3. increased length of the pipe
Playing detective to discover which factors are involved in my patient's high blood pressure is the next step.
Viscosity relates to how thick a fluid is, and the thicker the blood, the higher the pressure. Blood is composed of two elements: fluid, or plasma, and formed elements including red blood cells (RBCs), white blood cells, and platelets. Relative decreases in fluid--or a relative or absolute increase in RBCs--are common reasons why blood would be thicker. This situation is often seen when a patient is dehydrated.
Dehydration is more common than one would think and often contributes to my patients' blood pressure problems. It presents most commonly as an elevated or high normal hematocrit, a lab value expressed in percent--the percent of packed red blood cells to total volume of blood that has been processed in a centrifuged capillary tube (a small cylindrical glass tube). For menstruating females, I like to see a hematocrit of 36% to 42%. For males and postmenopausal females, I like to see a hematocrit of 38% to 44%. Oftentimes the normal reference ranges from a lab include pathology. Patients who are chronically dehydrated may have high blood pressure due to increased blood viscosity, and they may also present with other symptoms of dehydration such as headaches, low back pain, constipation, muscle cramps, thirst, and fatigue.
Kidneys play a role: Blood volume is controlled by the kidneys, organs that keep the concentration of electrolytes to fluid in blood at 300 milliosmols. Electrolytes include molecules such as sodium, potassium, calcium, and magnesium. When patients drink plain water, often they are diluting the concentration of electrolytes in their bloodstream. The kidneys then act to filter the excess water out through urination. I see this clinically: a patient will report drinking a glass or bottle of water and then urinating that same volume out 20 to 30 minutes later. I often ask patients to stop drinking plain water. I recommend instead that they always include some small source of electrolyte in each serving. This may be small amounts of a greens drink, a vitamin drink such as Emergen-C, calcium-magnesium powder or liquid, or sea salt. When patients are hydrating themselves, they report less frequent urination and less thirst--essentially, they are rebuilding their blood volume throughout the day. This is the issue with consuming refined table salt--purified sodium chloride. The electrolyte composition of table salt does not match the electrolyte composition of the body. The increase in serum levels of sodium after consuming table salt increases blood volume, and subsequently increases blood pressure. I recommend that patients consume high-quality sea salt, which mimics the natural electrolyte composition of the body. Clinically, I do not see exacerbation of blood pressure with sea salt. Finally, avoidance of diuretics such as caffeine and alcohol is helpful in maintaining proper blood volume.
Hormonal influences: Two hormones increase the production of red blood cells from the bone marrow: erythropoietin and testosterone. Patients taking testosterone should be monitored frequently for increases in red blood cell counts above physiological levels--which may contribute to elevated blood viscosity and elevated blood pressure.
Genetics: I have diagnosed a number of hemochromatosis or iron overload cases in my practice. Hereditary hemochromatosis involves an increase in iron absorption through the intestines and a subsequent increase in iron transport in the blood. This elevation of iron in the blood increases blood viscosity, and these patients can have elevated blood pressure. The most common way that I diagnosis hemochromatosis is to test serum ferritin--the carrier molecule for iron in the blood--in all of my patients. There are other reasons for elevated ferritin levels, such as infection, cancer, renal disease, and fever; however if a patient has an elevated ferritin and other causes have been ruled out, I assume that they have an iron storage disease. Treatment involves the prescription of monthly bloodletting through a blood service company. The problem with genetic testing is that not all the genetic abnormalities are included in the testing, so I will frequently prescribe blood-letting treatments without a genetic diagnosis and track the patient's blood pressure (to note if it falls in relation to the ferritin level). Many patients will report an increase in energy and an improvement in all symptoms when this oxidizing metal (iron) is lowered to normal levels in the blood.
MTHFR (methyltetrahydrofolate reductase) genetic abnormalities: This genetic condition involves abnormalities in a patient's ability to convert dietary folic acid into its active form in the body. Essentially, these patients need to consume the activated form of folic acid, 5-methyltetrahydrofolate, in supplement form. Researchers have found higher blood pressures in those with MTHF polymorphisms. (1) MTHF reductase mutations can be tested by conventional as well as specialty labs and would be a part of a complete hypertension workup.
Inflammation: Lastly, any process that increases inflammation in the bloodstream may lead to thicker blood. These processes may include smoking, low-grade infection, consuming microwaved food, excessive alcohol, birth control pills, food allergies, and autoimmune disease. With hypertension patients, I may work on treating an infection, take a patient off birth control pills, or make dietary changes that include removing food allergies. I've found testing hs-CRP levels in the blood to be a good marker of overall inflammation in the blood stream.
Fluid dynamic laws state that the longer the pipe, the higher the resistance (blood pressure) of fluid through that pipe. What does this translate to in humans? In a word: obesity. Obese individuals have more tissue than nonobese individuals, and thus their blood vessels grow longer to supply that excess tissue--and the pipe is longer. From population studies, two-thirds of hypertension can be directly attributed to obesity. (2) In an excellent article discussing the correlation between weight loss and blood pressure, investigators studied 595 men and women who were 10% to 65% above ideal weight, average age 43 years, with an average blood pressure of 127/86 millimeters of mercury. The participants received counseling to achieve weight loss and were compared with 596 control participants who were not given any weight-loss counseling.
At six months, when the weight loss was greatest, the diastolic blood pressure fell, on average, 2.7 millimeters of mercury. Those who lost the most weight--around 20 pounds--dropped their systolic blood pressures by 7 millimeters of mercury and their diastolic pressures by 5 millimeters of mercury. Those who managed to keep the weight off during the three-year period maintained their lower blood pressures. The authors concluded that "significant long-term reductions in blood pressure and reduced risk for hypertension can be achieved with even modest weight loss." (3)
Blood vessels can be divided into two main types: arteries and veins. Both have three layers; an internal layer called endothelium, a middle layer composed of smooth muscle, and an outer layer made from connective tissue. Veins have a low blood pressure compared with arteries, so when we describe pathology from elevated pressure, it is really the pressure in arteries that is detrimental.
Decreasing the diameter of an artery doesn't just increase the pressure in a relative fashion; the relationship is exponential. Thus, small decreases in pipe, or artery, diameter can cause dramatic elevations in blood pressure. So what decreases artery diameter? The two most common reasons would be atherosclerosis that "clogs" the pipe and contraction of the smooth muscle in the middle layer of arteries, contraction mediated by a host of hormonal and chemical mediators as well as the nervous system.
The etiology, or cause, of atherosclerosis is a topic too broad to address in this article. However, I will say that both atherosclerosis and hypertension interact in a feed-forward process. Increased blood pressure damages the inside walls of arteries through increased shearing force, and this promotes and accelerates atherosclerosis. Atherosclerosis narrows artery diameter, and this in turn promotes and accelerates elevated blood pressure.
Can atherosclerosis be reversed? Absolutely. From this standpoint, the blood pressure will also drop substantially. Clinically, I've seen chelation therapy, diet, exercise, lifestyle, and nutrient therapy aid in reversing atherosclerosis. Smooth muscle forms the middle layer of arteries (tunica media) and will contract (vasoconstrict) and relax (vasodilate). This muscle receives innervation from the autonomic nervous system--the branch of the nervous system that controls automatic body functions such as heart rate, digestion, and respiratory rate. To be in sympathetic mode ("fight or flight") will increase blood pressure; conversely, to be in parasympathetic mode ("rest and digest") will lower blood pressure. The hormones secreted during "fight or flight" reactions all work to raise blood pressure: rennin, epinephrine, aldosterone, and norepinephrine. Naturopathic physicians often measure epinephrine and norepinephrine levels via urine testing. Therefore, managing stress ("fight or flight" mode) can be paramount in lowering blood pressure. In fact, naturopathic treatments for anxiety and stress will often help with HTN. Eliminating caffeine, which triggers the release of the epinephrine and norepinephrine, can also lower blood pressure.
Nondrug Therapies for Hypertension
Whether it is through smooth muscle relaxation or decreasing inflammation, many herbs are helpful in lowering blood pressure.
* Rauwolfia serpentina: In a review of randomized controlled trials, Rauwolfia was shown to lower systolic blood pressure to the same degree as first-line antihypertensive drugs. Rauwolfia relaxes smooth muscle in the artery. (4)
* Ammi visnaga: Khella (the common name) is a vasodilator of smooth muscle by calcium channel blocking. (5)
* Allium sativa: Garlic has been shown in controlled trials to lower blood pressure similarly to first-line antihypertensive medications. This may be through relaxation of smooth muscle or decreasing platelet adhesion, which would decrease blood viscosity. (6)
* Beetroot: The common beet has been shown to lower blood pressure, according to an impressive article in the journal Hypertension. Researchers showed that drinking 500 milliliters of beet juice lowered blood pressure within an hour, and effects lasted for 24 hours. Beets are naturally high in nitrates. Dietary nitrate is a precursor for the molecule nitric oxide, a powerful vasodilator molecule produced by endothelial cells. (7)
* Olive leaf extract, with standardized levels of oleuropein: In a large randomized, double-blind study with 232 patients, olive leaf extract was compared with captopril, a common antihypertensive medication. After eight weeks, the systolic readings had decreased by an average of 11.5 mmHg in the olive leaf group and 13.7 mmHg in the captopril group. The diastolic readings had decreased by an average of 4.8 mmHg in the olive leaf group and 6.4 mmHg in the captopril group. (8)
Nutrients that Lower Blood Pressure
* Magnesium: Magnesium is one of the most common minerals in the body. It influences blood pressure by acting as a calcium channel blocker, thus relaxing the smooth muscle layer in blood vessels. (9)
* L-arginine: L-arginine is I of 20 amino acids, or protein building blocks, and is used to form nitric oxide in the body. Nitric oxide is produced locally by endothelial cells, and is a powerful vasodilator. (10)
* CoQ10: CoQ10 is a molecule necessary for the generation of ATP (the energy currency of cells). It is also a potent antioxidant, or quencher of free radicals. This lowering of free radicals in the bloodstream may lead to relaxation of arteries as well as lowered blood viscosity. A recent meta-analysis of clinical trials looked at the results from 12 clinical trials and reported that CoQ10 may lower systolic blood pressure by up to 17 points and diastolic pressure by up to 10 points without side effects. (11)
* Folic acid: Multiple regression analysis showed, in a small study with 26 patients, after correcting for age, gender, smoking, body mass index, glycated hemoglobin, low-density lipoprotein cholesterol, and homocysteine, that plasma folic acid concentration was an independent determinant of vasodilation. The authors propose that folic acid plasma concentration may have a direct effect on endothelium, promoting vasodilation. (12)
* EPA, an essential fatty acid from fish: The authors of a study with 59 men stated that "purified DHA [docosahexaenoic acid] but not EPA [eicosapentaenoic acid] reduced ambulatory blood pressure and heart rate in mildly hyperlipidemic men. The results of this study suggest that DHA is the principal omega-3 fatty acid in fish and fish oils that is responsible for their BP- and HR-lowering effects in humans." (13)
* Potassium: Consuming relatively high sodium amounts and lower potassium amounts in the diet triggers the release of aldosterone, a hormone from the adrenal glands that raises blood pressure. Potassium supplementation can be used to treat hypertension. (14) I will encourage patients to consume high-potassium foods such as vegetables, nuts, and seeds and eliminate high-sodium choices such as processed foods and foods from restaurants, both of which use high amounts of refined table salt. The DASH diet, used by allopathic physicians to lower blood pressure, is essentially a diet with a higher proportion of potassium-rich foods and a lower proportion of sodium-rich foods. (15)
Fructose--More Foe Than Friend
Recent research has linked fructose to high blood pressure. Fructose is the main sugar in fruit, but is also found in an alarmingly high number of processed foods, from ketchup to soda. As fructose is detoxified from the body, it raises uric acid levels. A number of studies have linked higher uric acid levels to higher blood pressure levels. (16) Fructose also decreases nitric oxide and upregulates two of the most potent vasoconstrictors, endothelin-1 and angiotensin II, in animal models. (17), (18) So many patients have been told to eat fruits and vegetables, and that fruit is a health food. They look astonished when I ask them to avoid all fruit in their diet and to do a trial of 2 weeks without any fructose--from fruit and/ or as an addition to processed foods. I then ask them to challenge fructose in and measure a change in blood pressure. For those who are sensitive, lowering fructose intake to less than 10 grams daily is often helpful.
Hormones Relax Blood Vessels
The most powerful relationships I have seen clinically are those between progesterone, Cortisol, and high blood pressure. Progesterone relaxes blood vessels, initiates vasodilation, and can reduce hypertension. I will consider bioidentical progesterone treatment in both men and women. (19) High Cortisol levels naturally raise blood pressure, so I also work to lower this hormone in my patients.
Exercise Moves Blood through the Pipes
Exercise is a big component in a weight loss program and, in that way, can lower blood pressure by decreasing the length of the pipe. However, exercise also has other beneficial effects, In one study, researchers found both continuous cardiovascular exercise and interval cardiovascular exercise helpful in lowering blood pressure. The researchers stated that "continuous and interval exercise training were beneficial for blood pressure control, but only interval training reduced arterial stiffness in treated hypertensive subjects." (20) In another study comparing continuous and interval training, researchers reported that both types of cardio exercise were effective in improving blood pressure; however, interval training was superior in improving cardiorespiratory fitness, blood pressure, norepinephrine levels, and nitric oxide levels. (21)
Let's recall that hypertension is a symptom of an underlying imbalance. My workup may include the following:
* CBC (complete blood count) which includes red blood cell count, platelet count, white blood cell count, and hematocrit looking for underlying infection, elevated inflammation, and/or low grade dehydration
* Hs-CRP to rule out high levels of inflammation, which cause thicker blood
* CMP (comprehensive metabolic panel) to look at electrolyte levels and kidney function
* serum aldosterone, a hormone that raises blood pressure, related to potassium intake
* heavy metal testing
* urine epinephrine and norepinephrine levels--elevated when patients are under stress
* hormone testing, which includes progesterone, testosterone, and cortisol levels
* MTHF reductase polymorphisms (can be run through regular labs such as LabCorp)
* serum ferritin
* TSH, free T3, and free T4--thyroid hormone levels influence blood pressure
* genetic testing for hemochromatosis--several online companies offer inexpensive options
* coronary calcium score/carotid artery thickness to assess level of atherosclerosis
* in rare cases: rule out pheochromocytoma, renal artery stenosis, or hyperparathyroidism
Treatments strategies, depending on the underlying cause:
* elimination of caffeine, alcohol, refined table salt, and microwaved food
* fluid balance and correction of low-grade dehydration
* whole-foods diet with focus on fresh vegetables, nuts, and seeds
* potential restriction of fructose, including fruit and fruit juice, in the diet
* stress reduction, which will lower stress hormones and sympathetic innervation to blood vessel smooth muscle
* use of herbal and nutrient therapies
* bloodletting/blood donation if the patient has hemochromatosis or elevated ferritin
* hormone balancing, including lowering high testosterone and high Cortisol levels and supplementing low progesterone levels
* weight loss
* reducing inflammation in the blood
* instruction on cardiovascular interval training
The main difference between appropriate care and "Band-Aid" care is the time that it takes to discover the reasons behind a patient's high blood pressure. From a naturopathic perspective, which involves discovering the underlying cause, simply giving an antihypertensive medication without a work-up is covering up a symptom, and not removing disease. This takes time, investigation, and proactivity on both the part of the physician and the patient. In my practice, most hypertensive patients never need the drug.
(1.) El Din Hemimi NS, Abd El Salam MM, Elwahab MA. Polmorphism of methylene-tetrahydrofolate reductase (MTHFR) and susceptibility to hypertension. FASEB /. April 2008. 22(meeting abstract suppl)238. Available at www.fasebj.org/cgi/content/meeting_abstract/22/2_MeetingAbstracts/238.
(2.) Krauso RM, Winston M, Fletcher BJ, Grundy SM. Obesity: impact on cardiovascular disease. Circulation. 1998;98:1472-1476.
(3.) Stevens VJ et al. Long-term weight loss and changes in blood pressure. Ann Intern Med. January 2, 2001;134:1-11.
(4.) Shamon SD, Perez Ml. Blood pressure lowering efficacy of reserpine for primary hypertension. Cochrane Database Syst Rev, 2009 Oct 7;4:CD007655.
(5.) Von Blumroder WO. Therapy of heart disease with khellin, with special reference to the khellinstrophanthin. Dtsch Med /. 1959 Apr 1; I0(6):1 76-1 79.
(6.) Sobenin IA, Andrianova IV, Fomchenkov IV, Gorchakova TV, Orekhov AN. Time-released garlic powder tablets lower systolic and diastolic blood pressure in men with mild and moderate arterial hypertension. Hypertens Res. 2009 Jun: 32(6):433-437.
(7.) Webb, A el al. Acute blood pressure lowering, vasoprotective, and antiplatelet properties of dietary nitrate via byconversion to nitrite. Hypertension. 2008;51 (3):784-790.
(8.) Susalit, E et at Olive leaf extract effective in patients with stage-1 hypertension: comparison with captopril. Phytomedicine. 2011 Feb 15;18(4):251-258.
(9.) Halzislavri LS, Sarafidis PA, Georgianos PI, et al. Oral magnesium supplementation reduces ambulatory blood pressure in patients with mild hypertension. Am J Hypertens. 2009 Oct;22(10):1 070-1 075.
(10.) Miller AL. The effects of sustained-release-L-arginine formulation on blood pressure and vascular compliance in 29 healthy individuals. Ahem Med Rev. 2006 Mar;11(1):23-29.
(11.) Rosenfeldt FL, Haas SJ, Krum H, Hadj A, Leong JY, Watts, CF. Coenzyme Q10 in the treatment of hypertension: a meta-analysis of the clinical trials. J Hum Hypertens. 2007;21(4):297-306.
(12.) Mangoni AA, Sherwood RA, Swift CG, Jackson SH. Folic acid enhances endothelial function and reduces blood pressure in smokers: a randomized controlled trial. J Intern Med. 2002;252.6:497-503.
(13.) Mod TA, Bao DQ, Burke V, et al. Docosahexaenoic acid but not eicosapentaenoic acid lowers ambulatory blood pressure and heart rate in humans. Hypertension. 1999;43:253-260.
(14.) Dickinson HO, Nicolson Dj, Campbell F, Beyer FR, Mason J. Potassium supplementation for the management of primary hypertension in adults. Cochrane Database Syst Rev. 2006;19.3:CD004641.
(15.) Dash for Health [website], www.dashforhealth.com.
(16.) lohnson Rj, Segal MS, Sautin Y, et al. Potential role of sugar (fructose) in the epidemic of hypertension, obesity and the metabolic syndrome, diabetes, kidney disease, and cardiovascular disease. Am I Clin Nutr. 2007 Oct;86(4):899-906.
(17.) Miatello R, Risier N, Castro C, Gonzalez S, Ruttler M, Cruzado M. Aortic smooth muscle cell proliferation and endothelial nitric oxide synthase activity in fructose-ted rats. Am I Hypertens. 2001 Nov; 14(11 Pt 1):11 35-1141.
(18.) Tran, LT, MacLeod KM, and ). H. McNeill. Endothelin-1 modulates angiotensin II in the development of hypertension in fructose-fed rats. Mol Ceil Biochem. 325(1-2):89-97.
(19.) Rylance PB, Brincat M, Lafferty K, De Trafforcl |C, Brincat S, Parsons V, Studd JW. Natural progesterone and antihypertensive action. Br Med I (Clin Res Ed). 1985 Jan 5; 290(6461):13-14.
(20.) Guimaraes CV, Ciolac EG, Carvalho VO, D'Avila VM, Bortolotto LA, Bocchi EA. Effects of continuous vs. interval exercise training on blood pressure and arterial stiffness in treated hypertension. Hypertens Res. 2010 Jun;33(6):627-632.
(21.) Ciolac EG, Bocchi FA, Bortolotto LA, Carvalho VO, Greve JM, Guimaraes GV. Effects of high-intensity aerobic interval training vs. moderate exercise on hemodynamic, metabolic and neuro-humoral abnormalities of young normotensive women at high familial risk for hypertension. Hypertens Res. 2010 Aug;33(8):836-843.
by Amy Terlisner, NMD
Dr. Amy Terlisner attended the University of Georgia in Athens, Georgia, where she obtained a BS in holistic medicine, a degree that she customized for her later studies in naturopathic medicine. She graduated summa cum laude (with highest honor) and published an undergraduate thesis in health psychology. Dr. Terlisner then attended Bastyr University in Seattle, Washington. She has an extensive teaching background and has taught physiology, anatomy, clinical laboratory diagnosis, pharmacognosy, I physical exam diagnosis, and manipulation at the doctorate level. Her specialties include women's health, cardiovascular disease, gastroenterology, anti-aging medicine, and natural hormone replacement therapy. Dr. Terlisner is the current president of the Arizona Association of Naturopathic Physicians and owns ALETRIS Center of Integrative Medicine, located in Scottsdale, Arizona.