Reducing High Blood Pressure: Evidence-Based Natural Therapies

In day-to-day practice, many practitioners encounter patients with hypertension problems that are not being managed effectively. Some patients will discontinue with their prescribed medications because of undesirable side-effects, or for other reasons.

As natural health practitioners, we are often asked if there are any dietary supplements or nutritional therapies that can lower blood pressure in a more natural way without producing unwanted side-effects. Research studies conducted over the past 15 years support the use of specific dietary and supplementation practices, and participation in physical activity as natural interventions to reduce high blood pressure. In some cases these natural solutions are all that are required to control blood pressure; in other cases theses practices can significantly lower the requirement for medication, helping to reduce the likelihood of adverse side-effects occurring from the use of these drugs.

Trends in Hypertension

High blood pressure affects approximately 25 percent of the adult population in developed countries like the U.S. and Canada. In up to 75 percent of these cases, hypertension manifests in a mild form, which is highly sensitive to nutrition, supplementation and lifestyle practices.^1,22 Even the most current medical literature stresses that people with documented hypertension should receive intensive nonpharmacologic therapies to improve control of their condition and reduce the risk of developing further cardiovascular disease.² Hypertension, hypercholesterolemia and cigarette smoking are considered the cardinal risk factors for cardiovascular disease. Studies indicate that lowering a patient's blood pressure from 160/90 to 140/80 mmHg may decrease the risk of heart disease by more than 30 percent.³

From a medical standpoint, the use of anti-hypertensive drugs dominates the management of these conditions, and little attention is often given to nutrition and lifestyle approaches. However, many patients discontinue their drug regiment due to side-effects from these drugs, which can include fatigue; male impotence; elevated cholesterol levels; light-headedness; dizziness; and skin eruptions.⁴ In Canada, 22 percent of adults have hypertension, but only 16 percent of this population are treated and controlled. This leaves 84 percent of hypertensive patients uncontrolled and sometimes unaware that this silent killer is even present.^5,6 In general, hypertension across the population is not well controlled. An effort by alternative health care providers to help remedy this situation is urgently needed, as cardiovascular disease continues to be the leading cause of premature death in our society.

Effective Nutritional Therapies and Lifestyle Interventions

Weight loss: Hypertensive patients who are overweight experience a drop to normal in their readings in approximately two-thirds of cases by simply losing 10-15 pounds.^7,8 Overweight patients tend to display insulin resistance, especially in cases where there is a propensity for abdominal weight gain (android obesity). Insulin resistance results in higher secretion rates of insulin to help overcome the resistance to insulin displayed by peripheral body cells.

One of the consequences of hyperinsulinemia is increased retention of sodium by the kidneys, which tends to drive up blood pressure in sodium-sensitive individuals. Thus, moderate weight loss helps to reverse insulin resistance, lowering basal and postprandial insulin blood levels. This, in turn, encourages less sodium retention and a natural lowering of blood pressure. It is estimated that in up to half of adults in the U.S. whose hypertension is being pharmacologically managed, the need for drug therapy could be alleviated with only modest reductions in body weight.⁹

In conjunction with dietary advice to help reduce excess weight, engaging in regular endurance-based exercise (at least 40-60 minutes of brisk walking four to five times per week) has been shown to help reduce high blood pressure. Exercise further increases insulin sensitivity, accelerates weight loss, and induces other changes within the cardiovascular system to lower blood pressure.^6,10 Clearly, health practitioners should become more involved in providing patients with safe and effective nutrition and lifestyle practices that reverse weight gain and enhance the patient's overall level of cardiovascular fitness.

Lower alcohol consumption: Studies indicate that excess alcohol consumption is a culprit in hypertension. Restricting alcohol consumption to two or fewer drinks per day (fewer than 14 weekly for men, and nine for women) has been shown to help lower blood pressure in individuals who consume alcohol.⁷

Sodium restriction: Approximately 40-50 percent of hypertensive patients are thought to be sensitive to sodium intake, which is at least a partial cause of their problem. Salt sensitivity appears to be more common among blacks, diabetics and the elderly. Reducing sodium intake to 2000 mg per day is a prudent step in the global management of hypertension. This requires restricted use of discretionary salt, and avoiding heavily salted processed foods (e.g., prepared soups, pickles, salted snacks, foods containing MSG, etc.)^7,11,12,13

Calcium supplementation: A number of well-designed human intervention trials reveal that calcium supplementation (1,000-1,500 mg calcium per day as calcium carbonate or citrate) can lower blood pressure, particularly in sodium-sensitive hypertensive patients. Calcium encourages sodium excretion by the kidneys and, in concert with magnesium, helps to relax the smooth muscle lining of arterioles, lowering diastolic pressure.^11,14,35 Calcium and magnesium supplements are best taken with meals for this purpose, and to enhance their absorption.³³

Magnesium supplementation: Supplementation with 600 mg per day of magnesium has been shown to lower blood pressure in some, but not all, studies. Presently, a greater body of evidence exists for calcium supplementation than for magnesium. However, there is no risk in including 600 mg of magnesium in the management of hypertension (unless severe kidney disease is present).¹⁵

Omega-3 fat supplementation: Over 60 double-blind studies have demonstrated that either fish oil or flaxseed oil supplementation can be effective in lowering blood pressure. One tablespoon per day of flaxseed oil can lower systolic and diastolic blood pressure by up to 9 mm Hg.¹⁶ I generally recommend 1,000 mg of flaxseed oil (in capsule form) twice a day with meals.

Garlic extract supplementation: Supplementation with a garlic extract product that yields 4,000 mcg of allicin (between a half and a whole clove of garlic) may help to lower blood pressure. Reductions of 20-30 mm Hg systolic and 10-20 mm Hg diastolic pressure have been demonstrated. However, this effect varies greatly among hypertensive subjects.^2,17

Coenzyme Q10 supplementation: In recent years, a number of randomized, double-blind trials have demonstrated that coenzyme Q10 (CoQ10) supplementation can effectively and consistently lower blood pressure in hypertensive subjects. CoQ10 is directly involved in the bioenergetic pathways of ATP production in heart muscle (myocardium). Research reveals that 39 percent of patients with high blood pressure have a deficiency of CoQ10. Supplementation with CoQ10 appears to correct this deficiency, correcting the underlying metabolic abnormality that leads to high blood pressure development.

Most experts in this field believe that CoQ10 is able to lower blood pressure through its favourable influence on heart bioenergetic mechanisms and possibly relaxing vascular smooth muscle. Because CoQ10 corrects an underlying metabolic defect that leads to high blood pressure, lowering of blood pressure usually requires four to 12 weeks of CoQ10 supplementation.^18-21

In a recent randomized, double blind trial among patients receiving antihypertensive medications, the addition of 60 mg of CoQ10 twice daily was shown to markedly reduce both systolic and diastolic blood pressure. CoQ10 supplementation also reduced other risk factors for cardiovascular disease, including a lowering of fasting and two-hour plasma insulin, glucose, triglycerides, lipid peroxides and blood levels of malondialdehyde - a marker of free radical damage.

The authors of the study conclude that CoQ10 decreases blood pressure (possibly by decreasing oxidative stress, i.e., free radical generation) and insulin response in hypertension patients receiving conventional antihypertensive drugs. This study and others provide evidence that CoQ10 can be taken safely in conjunction with antihypertensive drugs to produce better blood pressure lowering outcomes.^22-24

The daily dosage of CoQ10 to aid in lowering blood pressure is usually 60 mg twice per day.²² A dosage of 100 mg once per day has been tested.¹⁶ In mild cases of hypertension, 30-75 mg once per day may be sufficient to normalize blood pressure.^23,24

Hawthorn extract supplementation: The hawthorn plant and its berries are a rich source of a unique strand of bioflavonoids known as procyanidins. Like CoQ10, these procyanidins have been shown to reverse congestive heart failure by enhancing bioenergetic pathways in the heart muscle (myocardium). More recently, we have seen a number of intervention trials that demonstrate that hawthorn extract supplementation can also effectively reduce high blood pressure.

The procyanidins in hawthorn act as cardiac glycoside agents that increase cyclic AMP and produce a vasodilatation of the arteries. The daily dosage required to lower blood pressure ranges from 100-250 mg, up to three times daily if taken as a sole antihypertensive agent. To ensure sufficient levels of its active constituents (procyanidins), the product must be standardized to five-percent flavanoid content (1-2% vitexin content). Usually two to four weeks is required to see a significant decline in blood pressure in hypertensive patients.²⁷ Hawthorn is contraindicated in patients taking digitalis or digoxin.³⁴

Summary

The World Health Organization has promoted lifestyle modification as an effective method of reducing high blood pressure and overall cardiovascular risk.24 A summary of effective natural antihypertensive interventions include:

Weight loss - Usually, only 10-15 lbs. of weight loss (in overweight subjects) will produce a significant blood pressure reduction in hypertensive patients.

Salt intake - Limit to 2-3 grams per day.

Alcohol consumption - Limit alcohol consumption to less than two drinks per day for men, and even less for women (maximum of nine drinks per week).

Exercise - endurance exercise 30-60 minutes per session a minimum of four times per week.

Calcium supplementation - 1,000-1,500 mg per day (calcium carbonate or citrate) taken in divided doses of 500 mg per dose (with food).

Magnesium supplementation - 600 mg per day (all at once or in divided doses, with food).

Flaxseed oil - 2,000 mg per day (two 1,000-mg capsules with meals).

Coenzyme Q10 - 60 mg twice per day is a popular treatment for hypertension.

Hawthorn - 75 mg twice per day (standardized to five percent flavanoid content) can be used provided the patient is not also taking digitalis or digoxin.

Garlic extract supplementation (optional) - yielding 4,000 mcg of allicin content.

Fruits and vegetables - at least five servings per day.

The preceding recommendations can be used in conjunction with standard antihypertensive drugs, if necessary. At present, there is sufficient evidence from well-designed medical intervention trials to show that lifestyle interventions are successful in reducing or eliminating the need for pharmacologic therapy in a high percentage of hypertensive patients.^29-32

References

1. Halpern S. (ed.) Quick reference to clinical nutrition. Nutrition and Cardiovascular Disease; J.B. Lippincott Company, Philadelphia, 1987:139-153.
2. Canadian Guidelines for Cardiac Rehabilitation and Cardiovascular Disease Prevention (Canadian Assoc. of Cardiac Rehab.) 1st edition, 1999;94-104.
3. Fowler FE. Myocardial infarction in the 1990s. Postgraduate Medicine May 1995;5:135-146.
4. Griffith HW. Complete Guide to Prescription and Non-Prescription Drugs (1999 edition). The Body Press 1998:168-169,194-195,54-55.
5. Murray CJLM, et al. Evidence-based health policy - lessons from the global burden of disease study. Science 1996;274:740-743.
6. Joffres MR, et al. Awareness, treatment, and control of hypertension in Canada. Am J Hypertens 1997;10(Pt-1):1097-1102.
7. 2000 Canadian hypertension recommendations (summary of recommendations affecting family physicians) - the Canadian Hypertension Recommendations Working Group. Canadian Family Physician April 2001;47:793-794.
8. Goodhart R, Shils M, Lea, Febiger. Modern Nutrition in Health and Disease (sixth edition): 733.
9. McCarron D, et al. Body weight and blood pressure regulation. Am J Clin Nutr 1996; 63(suppl):423-425.
10. Pate RR, et al. Physical activity and public health. JAMA Feb. 1, 1995;272,5:402-407.
11. McCarron D. Role of adequate dietary calcium intake in the prevention and management of salt-sensitive hypertension. Am J Clin Nutr 1997;62: 2(suppl):712-716.
12. Cappuccio F, et al. Double-blind randomized trial of modest salt restriction in older people. Lancet 1997;350;9081: 850-854.
13. Graudal N, et al. Effects of sodium restriction on blood pressure, rennin, aldosterone, catecholamines, cholesterols, and triglycerides. JAMA 1998;279:1383-1391.
14. Meese RB, et al. The inconsistent effects of calcium supplements upon blood pressure in primary hypertension. Am J Med Sci 1987;29:4219-4224.
15. Motoyama T, et al. Oral magnesium supplementation in patients with essential hypertension. Hypertension 1989; 13:227-232.
16. Murray M, Pizzorno J. Encyclopedia of Natural Medicine (2nd edition) Prima Publishing 1997;425-535.
17. Foushee DB, et al. Garlic as a natural agent for the treatment of hypertension. A preliminary report. Cytobios 1982;34:145-162.
18. Digiesi V, et al. Mechanism of action of coenzyme Q10 in essential hypertension. Curr Ther Res 1992;Res 51:668-672.
19. Langsjoen P, et al. Treatment of essential hypertension with coenzyme Q10. Mol Aspects Med 1994; Med 15 (suppl):265-272.
20. Digiesi V, et al. Coenzyme Q10 in essential hypertension. Mol Aspects Med 1994; Med 15 (suppl):257-263.
21. McCarty MF. Coenzyme Q versus hypertension: does CoQ decrease endothelial superoxide generation? Med Hypotheses 1999;53,4:300-304.
22. Singh RB, et al. Effect of hydrosoluble coenzyme Q10 on blood pressure and insulin resistance in hypertensive patients with coronary artery disease. J Hum Hypertens 1999;13,3:203-208.
23. Yamagami T, et al. Bioenergetics in clinical medicine: studies on coenzyme Q10 and essential hypertension. Research Comm. in Chem. Path and Pharmacol 1975;11,2: 273-288.
24. Yamagami T, et al. Bioenergetics in clinical medicine, VIII. Administration of coenzyme Q10 to patients with essential hypertension. Research Comm in Chem Path and Pharmacol 1976;14,4:721-727.
25. Murray M. Encyclopedia of Nutritional Supplements. PRIMA Publishing 1996:300-301.
26. Werbach MR. Nutritional Influences on Illness. Third Line Press, Inc. 1987:227-240.
27. Murray M, Pizzorno J. Encyclopedia of Natural Medicine (2nd edit) Prima Publishing 1997:524-535.
28. Petrella RJ. Lifestyle approaches to managing high blood pressure. Can Family Phys 1999;45:1750-1755.
29. Elmer JP, et al. Lifestyle intervention: results of the Treatment of Mild Hypertension Study. (TOHMS). Prev Med 1995;24:378-388.
30. Stamler R, et al. Nutritional therapy for high blood pressure. Final report of a four-year randomized controlled trial - the hypertension control program. JAMA 1987;257:1484-1491.
31. Iso H, et al. Community-based education classes for hypertension control: a 1.5-year randomized controlled trial. Hypertension 1996;27:968-974.
32. Appel LJ, et al. A clinical trial of the effects of dietary patterns on blood pressure (DASH-study) N Engl J Med 1997;336:1117-1124.
33. Levenson D, et al. A review of calcium preparations. Nutr Reviews 1994;52,7:221-232.
34. Shariff S, et al. Herbal fervor and vitamin vigor: Herbs and vitamins for cardiac disease. Perspective in Cardiology 2000;16,1:21-29.
35. McCarron D, et al. Blood pressure response to oral calcium in persons with mild to moderate hypertension. A randomized, double-blind, placebo-controlled, crossover trial. Ann Intern Med 1985;3,6:825-831.