By William Misner Ph.D.
I am disturbed that a recent [March 25, 2006] "methodology-questionable" paper published in BMJ (British Medical Journal) created concern and doubts regarding the proven dietary health-enhancing effect from intake of essential (often deficient) omega-3 fatty acids. With Omega-3 fatty acid deficiency, the increased risk of inflammation, cardiovascular heart disease, atherosclerosis, high blood pressure, heart arrhythmias, stroke, post exercise muscle recovery, and cancer increases dramatically. Only 2-9 grams per day of Omega-3 fatty acid is required to help prevent all of the above diseases. In my view, the value of consuming adequate Omega-3 fatty acids regenerates two important fatty acid metabolites, Docosahexaenoic Acid (DHA) and Eicosapentaenoic Acid (EPA) is of primary importance for health and health as it supports endurance performance.
ESSENTIAL FATTY ACID REQUIREMENT
Udo Erasmus is a scientist many consider the expert in dietary fatty acid metabolism resulting in optimal health. Erasmus writes in his published science text books that the human body is not capable of making two fatty acids (Omega-6 & Omega-3) and therefore for optimal health to reoccur, a daily dose of 9-18 grams Omega-6 and 2-9 grams Omega-3 should be consumed daily.
OMEGA FATTY ACID DEFICIENCY
Of the 70 diets I computer analyzed between 1996-2006, not one athlete or sedentary subject fulfilled their requirement for Omega-3 fatty acids, while all were consuming above their requirement for Omega-6 fatty acids. Omega-6 fatty acids taken the same time as Omega-3's will inhibit absorption of each other. If taken apart from Omega-6's, Omega-3 absorption rate will not be inhibited. We acted on this research several years back when we ceased manufacturing our premiere blend of Omega-6 and Omega-3 oils in favor of the North Sea DHA/EPA-rich Salmon Oil product made by Carlson's. Our American diet is excessive in the Omega-6's, we need only 81-162 calories per day or one-third to one half-ounce daily, yet most Americans consume much more than we need from breads, processed foods, canola oil, salad dressings etc.
OMEGA-3 HEALTH BENEFITS
Myriads of responsibly published research conclude the health effects from Omega-3-fish oils consumption are extraordinary. Salmon oil is highly regarded for its Docosahexaenoic Acid (DHA) and Eicosapentaenoic Acid (EPA) content. DHA and EPA presents remarkable health-enhancing effects against cardiovascular heart disease, atherosclerosis, high blood pressure, heart arrhythmias, stroke, post exercise muscle recovery, and cancer. To note this research only scratches the surface on the health benefits from Omega-3 fish oil consumption, either as whole fish or encapsulated supplements.
A myriad of representative summaries report health-enhancing effects from consumption of Docosahexaenoic Acid (DHA) and Eicosapentaenoic Acid (EPA) found in fish oil:
DOCOSAHEXAENOIC ACID (DHA)
Docosahexaenoic Acid is an (Omega-3) superunsaturated fatty acid (22:6w3) (22:6n3) which can be synthesized within the body or obtained from food. DHA normally comprises 2.1% to 7.5% of total fasting red blood cell fatty acids. DHA (1,500 mg per day) counteracts ARRHYTHMIAS (it reduces ventricular premature complexes associated with arrhythmias by approximately 50%). Sellmayer A. et al. (1995) & Landmark (1998) reported that DHA reduces the proliferation of the atherogenic plaque that is involved in the development of ATHEROSCLEROSIS. Sorrentino et al. (1991) showed that Omega-3 oils (including DHA) help to prevent the formation of abnormal blood clots. DHA lowers Fibrinogen and Apoprotein (a) levels within the body. DHA PREVENTS HEART ATTACKS, reducing the risk of abnormal blood clotting by preventing the blood's platelets from becoming too sticky.
Bonaa et al. (1990) reported that DHA LOWERS BLOOD PRESSURE in hypertension patients (by increasing the body's production of prostaglandin e1 and by inhibiting the production of aldosterone). Studies of whether polyunsaturated fatty acids in fish oil in particular, eicosapentaenoic and docosahexaenoic acids - LOWER BLOOD PRESSURE have varied in design and results. The authors conducted a population-based, randomized, 10-week dietary-supplementation trial in which the effects of 6g per day of 85 percent eicosapentaenoic and docosahexaenoic acids were compared with those of 6 g per day of corn oil in 156 men and women with previously untreated stable, mild essential hypertension. The mean systolic blood pressure fell by 4.6 mm Hg (P = 0.002), and diastolic pressure by 3.0 mm Hg (P = 0.0002) in the group receiving fish oil; there was no significant change in the group receiving corn oil. The differences between the groups remained significant for both systolic (6.4 mm Hg; P = 0.0025) and diastolic (2.8 mm Hg; P = 0.029) pressure after control for anthropometric, lifestyle, and dietary variables. The decreases in blood pressure were larger as concentrations of plasma phospholipid n-3 fatty acids increased (P = 0.027). Dietary supplementation with fish oil did not change mean blood pressure in the subjects who ate fish three or more times a week as part of their usual diet, or in those who had a base-line concentration of plasma phospholipid n-3 fatty acids above 175.1 mg per liter.
Eicosapentaenoic and Docosahexaenoic Acids REDUCE BLOOD PRESSURE in essential hypertension, depending on increases in plasma phospholipid n-3 fatty acids. Diep et al., concluded that Omega-3 fatty acids (n-3 FAs) are shown to exert a blood pressure-lowering effect in hypertension, possibly in part by influencing vascular structure. The authors previously demonstrated that n-3 FAs induce vascular smooth muscle cell (VSMC) apoptosis, which could exert an effect on the structure of blood vessels. In the present study, they investigated signaling pathways through which n-3 FAs mediate apoptosis in VSMCs. Cultured mesenteric VSMCs from Sprague-Dawley rats were stimulated with docosahexaenoic acid (DHA), a representative n-3 FAs. Morphological changes in apoptosis and DNA fragmentation were examined with phase-contrast microscopy and fluorescence microscopy with Hoechst 33342 staining. To clarify possible pathways of apoptosis, they evaluated the expression of phosphorylated p38 mitogen-activated protein kinases, bax, bcl-2, cytochrome c, and peroxisome proliferator-activated receptor-alpha (PPAR-alpha) with Western blot analysis. DHA treatment induced cell shrinkage, cell membrane blebbing, and apoptotic bodies in VSMCs. DHA time-dependently activated p38 mitogen-activated protein kinases, bax, PPAR-alpha, and cytochrome c, with maximal effects obtained after 5 and 30 minutes and 1 and 3 hours, respectively. SB-203580 and SB-202190, selective p38 inhibitors, reduced DHA-elicited apoptosis and expression of PPAR-alpha but had no effect on the expression of bax or cytochrome c. The present results indicate that DHA induces apoptosis in VSMCs through >/=2 distinct mechanisms: (1) a p38-dependent pathway that regulates PPAR-alpha and (2) a p38-independent pathway via dissipation of mitochondrial membrane potential and cytochrome c release. The death-signaling pathway stimulated by DHA may involve an integration of these multiple pathways. By triggering VSMC apoptosis, DHA may play a pathophysiological role in vascular remodeling in cardiovascular disease.
Frenoux et al., (2001) reported that gamma-linolenic acid (GLA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have been reported to PREVENT CARDIOVASCULAR DISEASES. However, they are highly unsaturated and therefore more sensitive to oxidation damage. The authors investigated the effects of a diet rich in these polyunsaturated fatty acids (PUFA) on blood pressure, plasma and lipoprotein lipid concentrations, total antioxidant status, lipid peroxidation and platelet function in spontaneously hypertensive rats (SHR) and normotensive Wistar Kyoto rats (WKY). Five-week-old SHR and WKY rats were fed for 10 wk either a diet containing Isio 4 oil or a diet rich in GLA, EPA and DHA (5.65, 6.39 and 4.94 g/kg dry diet, respectively). The total antioxidant status was assayed by monitoring the rate of free radicalinduced hemolysis. VLDL-LDL sensitivity to copper-induced lipid peroxidation was determined as the production of thiobarbituric acid reactive substances. After dietary PUFA supplementation, a significant decrease in blood pressure of SHR rats (-20 mm Hg) was observed and the total antioxidant status was enhanced. VLDL-LDL resistance to copper-induced peroxidation was increased in both strains. The PUFA supplementation did not change platelet maximum aggregation in SHR rats, but it decreased the aggregation speed. In hypertensive rats, GLA + EPA + DHA supplementation lowers blood pressure, enhances total anti-oxidant status and resistance to lipid peroxidation, diminishes platelet aggregation speed and lowers plasma lipid concentrations. Thus, it enhances protection against cardiovascular diseases.
From Mori et al., (1999) suggest that in animal studies 2 major omega3 fatty acids found in fish, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), may have DIFFERENTIAL EFFECTS ON BLOOD PRESSURE AND HEART RATE. They determined whether there were significant differences in the effects of purified EPA or DHA on ambulatory blood pressure and heart rate in humans. In a double-blind, placebo-controlled trial of parallel design, 59 overweight, mildly hyperlipidemic men were randomized to receive 4 grams per day of purified EPA, DHA, or olive oil (placebo) capsules and continued their usual diets for 6 weeks. Fifty-six subjects completed the study. Only DHA reduced 24-hour and daytime (awake) ambulatory blood pressure. Relative to the placebo group, 24-hour blood pressure fell by 5.8/3.3 (systolic/diastolic) mm Hg and daytime blood pressure fell 3.5/2.0 mm Hg with DHA. DHA also significantly reduced 24-hour, daytime, and nighttime (asleep) ambulatory heart rates. Relative to the placebo group, DHA reduced 24-hour heart rate by 3. 5+/-0.8 bpm, daytime HR by 3.7+/-1.2 bpm, and nighttime HR by 2. 8+/-1.2. EPA had no significant effect on ambulatory blood pressure or heart rate. Supplementation with EPA increased plasma phospholipid EPA from 1.66+/-0.07% to 9.83+/-0.06% but did not change DHA levels. Purified DHA capsules increased plasma phospholipid DHA levels from 4.00+/-0.27% to 10.93+/-0.62% and led to a small, nonsignificant increase in EPA (1.52+/-0.12% to 2.26+/-0.16%). Khosh (2001) and Hirafuji et al. (1998) also support this conclusion.
Purified DHA but not EPA reduced AMBULATORY BLOOD PRESSURE AND HEART RATE in mildly hyperlipidemic men. The results of this study suggest that DHA is the principal omega3 fatty acid in fish and fish oils that is responsible for their blood pressure and heart rate lowering effects in humans. Prisco et al., (1998) examined sixteen mild essential hypertensive male outpatients and 16 normotensive male controls were randomly assigned to receive either DHA (1.4 grams per day) + EPA (2.04 grams per day) or olive oil (4 grams per day) as a placebo for four months. After two months of treatment, systolic blood pressure decreased by an average of 6 mm Hg and diastolic blood pressure fell by an average of 5 mm Hg. Similar findings were also reported by Morris et al. (1993).
Okada M. et al. (1996) tested the possibility that DHA supplements might IMPROVE MENTAL FUNCTIONING IN PATIENTS WITH MODERATELY SEVERE DEMENTIA FROM THROMBOTIC STROKE. DHA is enriched in brain tissues and plays an important role in sensory functions. It also has electrical stabilizing effects and is antithrombotic. Twenty male and female elderly patients (average age 83) with mild to moderate dementia due to stroke(s) were studied. Patients were divided into two groups, one of which received DHA, while the other received placebo. Each day, the DHA group received 720 mg of DHA daily for a year. In the elderly with moderately severe dementia, the DHA supplementation improved their dementia scores (as determined by the Hasegawa's Dementia rating scale and the Mini-Mental State Examination scale). Terano et al. (1999) reported that DHA helps to prevent and alleviate the dementia that often results from strokes. DHA protects the brain from many of the TOXIC AFTER-EFFECTS OF STROKE (this means that people who supplement with or consume high dietary quantities of DHA prior to experiencing a stroke will experience less cognitive impairment and brain damage following a stroke).
CANCER & MUSCLE RECOVERY
DHA stimulates the (normal) apoptosis of SOME TYPES OF CANCER CELLS. Numerous studies conclude that the anti-tumor effect of DHA is mainly related to its ability to induce (normal) apoptosis in cancer cells (in 2000 Monograph Fish Oil). Stubbs (1992) and Burke (1999) reported that DHA enhances the fluidity of the body's cell membranes (more so than any other fatty acid). DHA is important for the formation of cell membranes. DHA also concentrates in the cell membranes of the brain and nerve cells, nerve synapses, retina of the eye, inner ear, adrenal glands and sex glands.
EICOSAPENTAENOIC ACID (EPA) PREVENTS CARDIOVASCULAR DISEASES OR DISORDERS. Fish oil superunsaturated fatty acids have been reported to lower the frequency of angina attacks. Aucamp et al. (1993) and Hazra et al. (1999) report that EPA helps to prevent angina. Wood et al. (1987) and Salachas et al. (1994) concluded that there is an inverse association between dietary eicosapentaenoic acid intake and the risk of angina pectori. Salachas et al. (1994), Wood et al. (1987) and Hazra et al. (1999) concluded that there is an inverse association between dietary eicosapentaenoic acid intake and the risk of angina pectoris. They agree that fish oil superunsaturated fatty acids have been reported to lower the frequency of angina attacks. Landmark (1998) and Sellmayer et al. (1995) reported that EPA (900 mg per day) counteracts arrhythmias by reducing ventricular premature complexes associated with Arrhythmias by approximately 50%. Billman et al. (1997, 1994), Hazra (1999), and Sorrrento et al. (1996) agree that EPA helps to prevent Ventricular Fibrillation. Sorrentino et al. 1991 & Leaf et al., (1996) conclude that EPA can prevent ventricular fibrillation and sudden cardiac death. Aucamp et al. (1993) report that EPA inhibits the progression of Atherosclerosis. Saynor et al. (1982) and Sorrentino et al. (1991) EPA helps to prevent abnormal blood clotting by preventing the blood's platelets from becoming too sticky. Black et al. (1984) reported that EPA helps to prevent cerebral insufficiency (i.e. poor blood circulation to the brain). Gerbils were fed either a standard diet or a diet supplemented with menhaden fish oil (which is high in eicosapentaenoic acid (EPA) for two months. Ischemia was produced by bilateral carotid occlusion for ten minutes, followed by reperfusion for 60 minutes. In control animals, cerebral blood flow was decreased 30 and 60 minutes after reperfusion and brain water (edema) was increased. In gerbils receiving menhaden oil, cerebral blood circulation did not fall during reperfusion and edema did not occur.
Bonaa et al. (1990) & Engler et al.(1999) report that EPA (2,200 mg per day) lowers elevated blood pressure in hypertension patients (by stimulating the production of prostaglandins PGE3 and PGI3). EPA prevents many forms of heart disease: EPA (at least 400 mg per day) reduces the risk of heart attack and helps to prolong survival in people who have already experienced a heart attack). Burr et al. (1989) demonstrated that the addition of 2,500 mg of eicosapentaenoic acid (EPA) to the diet per week (corresponding to approximately 300 grams of fatty fish per week) lowered mortality by approximately 29% in men during the first two years after a heart attack (as measured b the men's susceptibility to ventricular fibrillation). EPA may reduce the infarct size in patients with acute myocardial infarction (heart attack). Landmark et al (1998) & Hazra et al. (1999) agree that the use of fish oils appears to reduce infarct size as estimated from peak creatine kinase and lactate dehydrogenase activities.
CONCLUSION: This article could easily contain at least 1000 other papers that support the dietary Omega-3 Docosahexaenoic Acid (DHA) and Eicosapentaenoic Acid (EPA) between 18-81 calories or 2-9 grams salmon oil per day. The BMJ single research paper is methodologically mixed in its concluding remarks. Some scientists interpret this research as supporting the use of pure wild fish omega-3 fatty oils is in fact neither disputed nor is the focus of the authors. I advise that unless the bulk of the research already reported is congruent, we ought to take any report that a natural essential metabolite will not do harm to human health except it be deficient or in excess.
REFERENCES
Aucamp et al. Pilot trial to determine the efficacy of a low dose of fish oil in the treat-ment of angina pectoris in the geriatric patient. Prostaglandins Leukot Essent Fatty Acids. 49:687-689, 1993.
Aucamp et al. Pilot trial to determine the efficacy of a low dose of fish oil in the treat-ment of angina pectoris in the geriatric patient. Prostaglandins Leukot Essent Fatty Acids. 49:687-689, 1993.
Billman et al. Prevention of ischemia-induced cardiac sudden death by n-3 polyunsaturated fatty acids in dogs. Lipids.32:1161-1168, 1997.
Billman et al. Prevention of ischaemia-induced ventricular fibrillation by omega 3 fatty acids. Proceedings of the National Academy of Sciences, USA. 91:4427-4430, 1994.
Black et al. Eicosapentaenoic acid: Effect on brain prostaglandins, cerebral blood flow and edema in ischemic gerbils. Stroke. 15(1):65-69, 1984.
Bonaa et al. Effect of eicosapentaenoic acid and docosahexaenoic acids on blood pressure in hypertension. New England Journal of Medicine. 322(12):795-801, 1990.
Bonaa, K. H., et al. Effect of eicosapentaenoic acid and docosahexaenoic acids on blood pressure in hypertension. The New England Journal of Medicine. 322:795, 1990.
Burke E. R. Fish oil supplementation prevents muscle breakdown. Muscular Development. 36(8):52, 1999.
Burr et al. Effects of changes in fat, fish, and fibre intakes on death and myocardial reinfarction; Diet and reinfarction trial (DART). Lancet. 334:757-761, 1989.
Diep et al. Docosahexaenoic acid, a peroxisome proliferator-activated receptor-alpha ligand, induces apoptosis in vascular smooth muscle cells by stimulation of p38 mitogen-activated protein kinase. Hypertension. 36(5):851-855, 2000.
Engler et al. Calcium-mediated mechanisms of eicosapentaenoic acid-induced relaxation in hypertensive rat aorta. Am J Hypertens. 12(12 Part 1-2):1225-1235, 1999.
Frenoux et al. A polyunsaturated fatty acid diet lowers blood pressure and improves antioxidant status in spontaneously hypertensive rats. Journal of Nutrition. 13 (1), 2001.
Hanson et al. Duration of effects of dietary fish oil supplementation on serum eicosapentaenoic acid and docosahexaenoic acid concentrations in dogs. Am J Vet Res. 59:7 864-868, 1998.
Hazra et al. Pharmacology and therapeutic potential of the n-3 polyunsaturated fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in fish oils. Indian Journal of Pharmacology. 31:247-264, 1999.
Hazra et al. Pharmacology and therapeutic potential of the n-3 polyunsaturated fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in fish oils. Indian Journal of Pharmacology. 31:247-264, 1999.
Hirafujiet al. Effect of docosanexaenoic acid on smooth muscle cell functions. Life Sciences. 62:1689-1693, 1998.
In-Tele-Health 2002 (from Hyperhealth Pro CD-ROM)
Khosh F. Natural approach to hypertension. Alternative Medicine Review. 6(6), 2001. Landmark K. Fish, fish oils, arrhythmias and sudden death. Tidsskr Nor Laegeforen. 118(15):2328-2331, 1998.
Landmark, K. Fish, fish oils, arrhythmias and sudden death. Tidsskr Nor Laegeforen. 118(15):2328-2331, 1998.
Leaf et al. Prevention of cardiac sudden death by N-3 fatty acids: a review of the evidence. J Intern Med. 240(1):5-12, 1996.
Monograph: fish oil. Alternative Medicine Review. 5(6), 2000.
Mori et al. Docosahexaenoic acid but not eicosapentaenoic acid lowers ambulatory blood pressure and heart rate in humans. Hypertension. 34(2):253-260, 1999.
Morris et al. Does fish oil lower blood pressure? A meta-analysis of controlled trials. Circulation. 88:523-533, 1993.
Okada M. et al. The chronic administration of docosahexaenoic acid reduces the spatial cognitive deficit following transient forebrain ischemia in rats. Neuroscience. 1(71):17-25, 1996.
Prisco et al. Effect of medium-term supplementation with a moderate dose of n-3 polyunsaturated fatty acids on blood pressure in mild hypertensive patients. Thromb Res. 91:105-112, 1998.
Salachas et al. Effects of a low-dose fish oil concentrate on angina, exercise tolerance time, serum triglycerides and platelet function. Angiology. 45:1023-1031, 1994.
Salachas et al. Effects of a low-dose fish oil concentrate on angina, exercise tolerance time, serum triglycerides and platelet function. Angiology. 45:1023-1031, 1994.
Saynor et al., Eicosapentaenoic acid, bleeding time and serum lipids. The Lancet. 2:272, 1982.
Sellmayer et al. Effects of dietary fish oil on ventricular premature complexes. The American Journal of Cardiology. 76:974-977, 1995.
Some References from: In-Tele-Health 2002 (from Hyperhealth Pro CD-ROM)
Sorrentino et al. Polyunsaturated fatty acids and atherosclerosis. Boll Chim Farm. 130(8):297-231, 1991.
Stubbs, C. D.The structure and function of docosahexaenoic acid in membranes. In: Essential Fatty Acids and Eicosanoids. Champaign, IL AOCS Press, 1992.
Terano et al. Docosahexaenoic acid supplementation improves the moderately severe dementia from thrombotic cerebrovascular diseases. Proceedings of the 3rd Congress of the International Society for the Study of Fatty Acids and Lipids, Lyon, France, June 1-5, 1998. Published in: Lipids 34(Supplement) S245, 1999.
Wood et al. Linoleic and eicosapentaenoic acids in adipose tissue and platelets and risk of coronary heart disease. Lancet 1(8526):177-183, 1987.
