|LE Magazine November 1998 |
Getting to The Heart of The Matter
Your heart knows that not all fats are bad. Omega-3 fatty acids in particular are often associated with improved cardiovascular health, including warding off heart attacks and stroke, as well as many other benefits.
Over the last 30 years, the public increasingly has become aware that excessive fat consumption is bad for one's health. Those who consume too much fat are at risk for cardiovascular disease, including heart attacks and stroke, and for developing such degenerative diseases as cancer, atherosclerosis, adult-onset diabetes and chronic inflammatory diseases.
However, fats are not all bad. The challenge lies in consuming an appropriate ratio of omega-6 to omega-3 fatty acids, and the fact is, Americans, on average, consume 10 to 20 times too much omega-6 fatty acids. Conversely, the reason that flax and fish oil are popular is because the omega-3 fatty acids found in these oils prevent and treat a wide range of degenerative diseases by favorably influencing the ratio of omega-6 to omega-3 fatty acids.
There is a remaining problem, however: Fish and flax oil, traditional sources of omega-3 fatty acids, can cause gastrointestinal side effects.
But there is good news to report. A new source of essential fatty acids, perilla oil, is showing greater health benefits without gastrointestinal side effects. Recent research suggests that perilla oil inhibits abnormal blood clotting, alleviates chronic inflammation, prevents certain types of arrhythmia, maintains cardiac cell energy output and preserves youthful cell membrane structure. It has even been shown to lengthen survival time of lab animals by 10 to 15 percent, compared with safflower oil, which is low in omega-3 fatty acids.
Here is a key point, since diseases of the heart are the number-one killer of Americans each and every year: Scientific studies show that alpha-linolenic acid reduces the incidence of stroke and second heart attacks, as well as breast and colon cancer. One study showed a 70-percent reduction in second heart attacks in those consuming this type of fatty acid. In addition, it works fast.
Perilla oil contains an abundance of alpha-linolenic acid-an omega-3 fatty acid-that humans require to sustain life. A review of the scientific literature indicates that perilla oil which comes from the beefsteak plant (Perilla frutescens) and is relatively common in East Asian countries-may be superior to other oils, and is tolerable by virtually everyone.
Sudden cardiac death due to ventricular tachyarrhythmia (irregular heart rhythms) is a leading cause of death in industrialized countries, and its prevention remains an unsolved problem. The mechanisms that trigger these arrhythmias are not completely understood. Whereas pharmacotherapy has been successful in other major causes of cardiovascular mortality, antiarrhythmic drugs have a disappointing record in the treatment of arrhythmias.
Most adults at risk of sudden cardiac death in industrialized societies suffer from atherogenic dyslipidemias-abnormal lipid levels-and coronary heart disease. Unlike symptom-suppressive antiarrhythmic therapy, interventions that target pathogenic mechanisms of dyslipidemia may prevent the generation of arrhythmogenic cells.
Atherogenic dyslipidemias have been shown to be associated with a systemic proinflammatory, pro-thrombotic state manifested by elevated levels of white blood cells, platelet activation, an increase of inflammatory cytokines, increased levels of adhesion molecules (integrins, selectins) and raised hemostatic (clotting) factors. The actions of these increased non-specific effectors of inflammation are interrelated. It has been suggested that the proinflammatory, pro-thrombotic state of hyperlipidemia-a general term for elevated concentration of any or all of the lipids in the plasma-is induced by modified or oxidized lipids such as phospholipids acting through the platelet-activating factor receptors, leukotrienes and oxysterols.
Fish oil has been popular because studies show that those who consume cold-water fish in their diets have dramatically lower risks of coronary artery disease. In addition, fish oil has been specifically shown to inhibit abnormal platelet aggregation in laboratory studies, and it is by this mechanism that fish oil prevents both heart attack and thrombotic stroke. However, perilla oil has been shown in one recent study to be superior to fish oil in reducing platelet aggregation, and was shown not to increase the risk of hemorrhagic stroke in rats.
In that study, rats were fed either a high linoleic safflower oil diet, a high alpha-linolenic perilla oil diet, an EPA (fish oil)-supplemented, or a DHA (fish oil)-supplemented safflower oil diet for four to five weeks. It was reported, "...The efficacies to reduce leukotriene B4 synthesis in calcium ionophore-stimulated neutrophils were the highest in the high alpha-linolenic acid diet, followed by the EPA diet and then the DHA diet. A significant reduction of platelet activating factor synthesis was observed in the high alpha-linolenic acid group, but not in the EPA nor the DHA groups, as compared with the high linoleic acid group." By limiting the synthesis of PAF and LTB4, a diet high in alpha-linolenic acid may help to control the proinflammatory, pro-thrombotic state associated with irregular heart rhythms and sudden cardiac death.
There is a general consensus that serum cholesterol is the major risk factor for the development of coronary heart disease, but this consensus may not be correct. Recently, the results of the 25-year follow-up study on plasma cholesterol and coronary heart disease mortality in seven countries were summarized. In northern Europe and the United States, the mortality rose with increased plasma total cholesterol, but such a relationship was not apparent in Japan. A similar difference was seen comparing data from the Mediterranean area and Northern Europe at 250 mg/dL cholesterol. There was an eight-fold difference in coronary heart disease mortality between West Scotland and Catalonia in Spain, without significant differences in blood cholesterol concentration.
These observations clearly indicate that, while plasma cholesterol is one of the risk factors for coronary heart disease, other factors can be more important. It is now becoming obvious that Western diets contain too many of the artery-clogging saturated fats, and not enough friendly fats that provide the body with EPA and DHA.
Experimental studies suggest that an intake of 3 to 4 grams per day of alpha-linolenic acid is necessary to obtain the protective effect against coronary heart disease.
|How Fatty Acids Work|
Entire textbooks have been written to describe the complex mechanisms by which the body utilizes fats. Many people are intimidated by the organic chemistry of fatty acid metabolism and fail to understand why the body requires proper fatty acid balance. Here is an explanation.
The four polyunsaturated fatty acid families can be identified by the precursor fatty acids, from which all other polyunsaturated fatty acids in that family can be derived, namely, oleic, palmitoleic, linoleic and alpha-linolenic acids. Mammals cannot synthesize linoleic acid or alpha-linoleic acid. Because a lack of omega-6 or omega-3 fatty acids results in various health disorders, these two polyunsaturated fatty acid families are termed "essential," and must be derived from the diet. For example, corn and sunflower oils are rich in linoleic acid (omega-6), perilla oil is rich in alpha-linoleic acid (omega-3), and various oils of marine origin also are rich in long-chain omega-3 fatty acids. These include eicosapentenoic (EPA) and docosahexanoic (DHA) acids.
Although the essential fatty acids are believed to protect against some human diseases, such as cardiovascular and central nervous system disorders, high amounts of omega-6 essential fatty acids have been associated with increased risk of breast, colon, pancreas and prostate cancer. For breast cancer in particular, experiments with laboratory animals have linked linoleic acid to increased tumor incidence, growth and metastasis, whereas the omega-3 fatty acids have a protective effect against the disease.
Considering the diverse physiological roles of the essential fatty acids as components of cell membranes and precursors of biologically active eicosanoids (hormone-like prostaglandins, leukotrienes, etc.), together with their varying structural and physical properties and susceptibilities to oxidative damage, their involvement in human disease is hardly surprising.
Alpha-linoleic acid is a rich source of omega-3 fatty acids, EPA and DHA, and there are literally thousands of published scientific papers showing that a deficiency of these fatty acids induces degenerative disease. The book Smart Oils is 207 pages long, and it only deals with neurological benefits of EPA and DHA. A comprehensive book that relates all the benefits that have been discovered about EPA and DHA would consume over a thousand pages. -
Stroke-prone spontaneously hypertensive rats develop the highest blood pressure among available rat strains, and frequently die of intracranial hemorrhages. Using this animal model, it was recently shown that the survival time is significantly longer in groups fed fish oil or perilla oil, compared with groups fed rapeseed, soybean, safflower or evening primrose oil.
In a recent paper, scientists re-evaluated the possible adverse effects of excessive intake of dietary essential fatty acids by measuring in rats the proliferation of certain enzyme-rich bodies called peroxisomes, as well as mitochondrial enzyme activity and the incidence of intracranial hemorrhages. When the animals were fed diets containing either fish oil or perilla oil, DHA accumulated in phospholipids of the liver and heart in the fish oil group, but not in the perilla oil group.
Also, feeding a diet containing 15 percent by weight of fish oil induced a significant proliferation of peroxisomes compared with a safflower oil diet, but the proliferating activity of perilla oil was much less. And fish oil or perilla oil did not accelerate the onset of cerebral bleeding in stroke-prone hypertensive rats. The study's conclusion was that, although proliferating activity of peroxisomes by excessive intake of fish oils should be noticed, these results provide evidence that omega-3 enriched oils are safe under conditions applicable to human nutrition. (It is also known that antioxidants like green tea and vitamin E can protect against oxidative stress caused by fish oil.)
The healthy body requires large amounts of the fatty acids EPA and DHA, which are made from omega-3. Regrettably, the typical Western diet provides large amounts of linoleic acid (omega-6) that in high amounts contributes to most forms of degenerative disease. The bad saturated fatty acids and its metabolites compete with the beneficial fatty acids EPA and DHA and their metabolites.
In addition to their cardiovascular protective effects, the right kinds of fatty acids have a great deal to do with keeping your brain functioning healthily. It's interesting to note that 60 percent of your brain is comprised of fatty materials, and that the type of fat we put in our mouths has a profound influence on neurological function. For nerves to grow, they need essential fatty acids as a raw material. For nerves and neurons to function, they need essential fatty acids to facilitate the cell's energy cycle. It has been shown in animals that the region of the brain associated with memory can actually grow new nerve cells, but this can't happen if the body lacks the essential fatty acids to provide the structural raw material.
The neurological disorders that can be caused by fatty-acid deficiencies range from depression to paralysis, learning disabilities and almost certainly senility. Fatty acids actually starred in a recent movie, Lorenzo's Oil, where supplementation with a specific fatty acid saved the life of a young boy who faced certain death.
In the introduction to his 1997 book, Smart Fats, Dr. Jeffery Bland describes the many mechanisms by which fats influence how our brain operates. Bland states that fats and oils affect: 1) learning, memory and mental intelligence; 2) mood, behavior and emotional intelligence; and 3) movement, sensation and physical intelligence (motor-neural control).
While the impact of aging on the brain is most evident, the role of chronic inflammation in aging-related diseases in general is becoming more evident, as studies show that Alzheimer's disease, atherosclerosis, valvular disease and even some cancers are mediated by inflammatory processes. Aging causes an inflammatory condition throughout the body, and essential fatty acids suppress chronic inflammation via well-defined mechanisms.
Those who take large amounts of anti-inflammatory drugs have lower rates of some aging-related diseases, but the dangerous side effects of these drugs preclude their everyday use. Essential fatty acids may provide the same protection as anti-inflammatory drugs without the side effects.
Prostaglandins are hormone-like chemicals formed in our bodies that produce both beneficial and harmful effects. Prostaglandin E2 is formed from an excess of a saturated fatty acid and promotes inflammatory processes. The consumption of the essential fatty acid found in perilla oil, alpha-linolenic acid, promotes the production of prostaglandin E3, which counteracts the production of the pro-inflammatory prostaglandin E2.
Tumor cells enriched with too much of the bad fatty acids often produce larger amounts of prostaglandin E2 which, in turn, suppress the host immune system and allow tumor cells to elude the host's defense system. The type of cancer cell dictates whether prostaglandin E2 production affects tumor cell proliferation.
Omega-3 essential fatty acids reduce production of the dangerous prostaglandin E2, and this in itself is a good reason for everyone to maintain proper fatty acid balance in the body.
The persistent overproduction of inflammatory products derived from bad fats may stimulate the proliferation of mutated cells, leading to an increased incidence of cancer. It was recently shown that both spontaneous breast tumorigenesis and chemical carcinogenesis in the breast, colon, rectum and prostate of rodents are better suppressed by dietary perilla seed oil, as compared with safflower oil. Soybean oil stimulated these cancers under the conditions examined. Perilla oil-derived fatty acids thus inhibit carcinogenesis, whereas excess linoleic acid from saturated fat are stimulatory.
Numerous human studies confirm that omega-3 essential fatty acids are effective in treating rheumatoid arthritis and other inflammatory diseases. Autoimmune diseases also are a culprit in neurological diseases that involve the destruction of the myelin sheath.
A large number of peer-reviewed publications from around the world have established the utility of dietary supplementation with omega-3 fatty acids in treating several chronic disease states. The key is providing the body with sufficient amounts of alpha-linolenic acid, as found in perilla oil, which then converts to the beneficial EPA and DHA fatty acids.
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