Guest guest Posted March 23, 2003 Report Share Posted March 23, 2003 Essential Fatty Acids: Their Role in Female Function JoAnn Guest Apr 30, 2002 09:56 PDT Essential Fatty Acids March 06, 2002 The media and advertising hype surrounding today's popular low- fat, no-fat, and even bad-- fat diets is inescapable. Women are prime targets for the " fat-phobic " or " fat-friendly " teachings (or ravings) of modern nutrition " experts. " In addition, many cleverly written labels fool consumers into thinking that foods such as no- fat pretzels and cookies are healthful. In the past, physicians saw patients who were suffering the consequences of a high-fat diet; now, they are seeing the effects of low-fat and bad-fat diets. To achieve optimal health, both physicians and patients need to learn a new nutritional term: *good* fat. High-quality fats and oils are necessary for maintaining good health and preventing certain chronic diseases. The body needs a specific ratio of saturated to monounsaturated fats. Some fats,specifically, the essential fatty acids (EFAs), or good fats-are as vital to physical function as are vitamins and minerals. Approximately 80% of US adults follow a diet that is deficient in EFAs. Processed " convenience " foods, which make up a large part of the US diet, are deliberately stripped of many EFAs to preserve shelf life. At the same time, people consume large quantities of foods heavy in saturated fats (eg, french fries, potato chips, crackers, baked goods, ice cream). This problem is compounded by a high intake of meat and shellfish containing arachidonic fatty acids, which can be harmful in excess. Thus, fats consumed in the typical US diet are dramatically out of balance with the body's true needs. EFAS AND PHYSIOLOGY Because of their contribution to prostaglandin formation, EFAs play many important roles in human physiology. They help to maintain cell membrane function; regulate pain, inflammation, and swelling; dilate and constrict blood vessels; mediate immune response; prevent blood clots; and regulate smooth-muscle responses, blood pressure (BP), nerve transmission, and cholesterol levels. EFA deficiency can lead to or aggravate various health problems in women and men, including rheumatoid arthritis, diabetic neuropathy, cardiovascular disease (CVD), mood instability, mental disorders, and skin conditions such as eczema. In women, it can also cause or exacerbate premenstrual syndrome (PMS), dysmenorrhea, abnormal menstrual bleeding, osteoporosis, breast disease, and menopausal symptoms. By contrast, an adequate amount of EFAs in the diet can reduce the risk for CVD, the leading cause of death in postmenopausal women in the United States. For gravidas, sufficient EFA intake can help to maintain a healthy pregnancy and to promote normal fetal development. The body cannot manufacture EFAs; these fatty acids must be obtained from the diet or through supplementation. The most important EFAs are linoleic acid (LA) and alpha-linolenic acid (ALA). LA belongs to the omega-6 family of fatty acids, whereas ALA belongs to the omega-3 family. Both omega-6 and omega-3 fatty acids are necessary for maintaining good health. Under ideal conditions, the body uses LA to produce gamma- linolenic acid (GLA) and ALA to produce eicosapentaenoic acid (EPA). GLA and EPA are then used to manufacture prostaglandins. Specifically, GLA is used to produce prostaglandin E^sub 1^ (PGE^sub 1^) and EPA, prostaglandin E^sub 3^ (PGE^sub 3^). As mentioned above, prostaglandins influence the function of virtually every system in the body, regulating inflammation, pain, BP, fluid balance, blood clotting, and hormone production and function. To maintain a proper ratio of antispasmodic and anti-inflammatory prostaglandins (PGE^sub 1^ and PGE^sub 3^) to prospasmodic and proinflammatory prostaglandins (PGE^sub 2^), the body must have an adequate and constant supply of each fatty acid, particularly GLA, ALA, and EPA. WOMEN'S HEALTH ISSUES Premenstrual Syndrome Although the role of serotonin in the pathophysiology of PMS has been established, this syndrome has also been linked to excessive and unbalanced prostaglandin production. Specifically, women with PMS may have a deficiency of PGE^sub 1^ in the central nervous system (CNS)1 and in cells such as breast tissue. Supplemental EFAs may help to increase PGE^sub 1^ production. The most popular and scientifically documented method of increasing PGE^sub 1^ production is through GLA supplementation, which has been shown to improve PMS symptoms such as headaches, depression, irritability, and bloating.2-4 GLA also relieves premenstrual breast pain and tenderness. Although evening primrose oil, borage oil, and black currant oil contain high quantities of GLA, only evening primrose oil has been studied for this purpose at 3000 and 4000 mg per day. Dysmenorrhea Foods that are high in arachidonic acid (eg, meat, shellfish) may contribute to dysmenorrhea. The body uses this acid to produce potentially harmful PGE^sub 2^, which causes muscle and uterine contractions. Optimal medicinal foods and oil supplements for relieving menstrual cramps are those that increase the antispasmodics PGE^sub 1^ and PGE ^sub 3^. Oily fish (eg, salmon, tuna, halibut, sardines, mackerel, herring) contain EPA, which helps to relax muscles by stimulating production of these prostaglandins. A study conducted on adolescents with dysmenorrhea showed that up to 73% rated the fish oil supplement " moderately effective " in relieving menstrual cramps.5 Seeds, nuts, and oils that contain ALA may also be helpful. The body converts the ALA to EPA, which is then used to produce muscle- relaxing prostaglandins. Supplementation with flaxseed oil, borage oil, and evening primrose oil are other ways to promote synthesis of antispasmodic prostaglandins and reduce uterine contractions. Clinical experience has shown that combinations of borage oil with flaxseed oil can be used at 3 capsules twice a day. Abnormal Menstrual Bleeding Flaxseeds contain phytoestrogens, particularly lignans. Flaxseed lignans can promote regular ovulation and help to lengthen the menstrual cycle by 1 to 3 days.6 Promoting regular ovulation improves fertility and normalizes progesterone levels, resulting in a more regular bleeding pattern. Lignans may also reduce the risk for breast cancer osteoporosis, and heart disease and they have favorable effects on selected menopause symptoms. Osteoporosis Research suggests that increased use of EFAs may help to optimize calcium metabolism and preserve bone health, thereby preventing osteoporosis. EFAs have been shown to increase calcium absorption from the intestines (in part by enhancing vitamin D effects), reduce urinary calcium excretion, increase calcium deposition in bone, and improve bone strength.7 Adults with osteoporosis who receive fish oil experience an increase in calcium levels and a reduction in urinary calcium clearance.8 GLA in particular has been shown to reduce calcium excretion,9 inhibit bone resorption, and increase calcium content in bone.10 Animal studies have shown that supplementation with large amounts of evening primrose oil (rich in GLA) and fish oil (rich in EPA and docosahexaenoic acid [DHA]) are more effective in inhibiting bone loss than are sunflower oil (rich in LA) and flaxseed oil (rich in ALA).11 Breast Disease According to studies, taking 3000-4000 mg per day of evening primrose oil has been found effective in relieving the discomfort of benign breast disease.12,13 Women with breast pain have unusually low concentrations of GLA and its metabolites. GLA metabolite levels increase and saturated fat levels decrease in the breast when patients receive evening primrose oil supplements. Borage oil, which contains more than twice as much GLA as does evening primrose oil, should also be considered for use in cyclic breast pain; however, without studies, it must be extrapolated that borage oil be used at 1500-2000 mg per day. Physicians and patients may be concerned about the possibility of an association between flaxseed oil use and breast cancer. In several studies, high levels of dietary ALA have been correlated with an increased risk for breast cancer.14-16 However, another study revealed a protective effect of ALA.17 Until more research findings are available, it may be advisable for women with breast cancer to forgo consumption of large amounts of flaxseed oil, or to use flaxseed oil only in conjunction with fish oil, evening primrose oil, or borage oil. In contrast, flaxseeds, with their high lignan and fiber content and their weak ability to block estrogen's effect on the breast, may be a valuable addition to the diet in preventing breast cancer. Fish oils also play a role in reducing breast cancer risk. The protective effect of omega-3 fatty acids was first observed in Greenland Eskimo women, who seem to have a strikingly low rate of breast cancer.18,19 These women follow a diet that may be the highest in the world in omega-3 fatty acids. The best diet may be one that balances ALA and GLA with EPA and DHA. Use of olive oil, which contains 76% oleic acid, may also reduce breast cancer risk. One study demonstrated that increased olive oil consumption was associated with a 25% lower risk of breast cancer in Greek women.20 Oleic acid is also found in evening primrose oil (7%), borage oil (15%-20%), black currant oil (10%), and canola oil (54%). Another study has interesting implications for women with breast cancer who are being treated with tamoxifen. In this study, patients received approximately 3 grams of GLA daily, resulting in a significant enhancement of tamoxifen response.21 Menopause Many women consume evening primrose oil or other GLA-containing oils to decrease menopause symptoms. One study showed that GLA in evening primrose oil reduced the maximum number of nighttime flushing episodes associated with menopause.22 Overall, however, the supplement did not differ from placebo in this regard. Many other herbal supplements are available to relieve menopause symptoms; these may be used in conjunction with EFAs for greater benefit. Pregnancy and Fetal Development EFAs play a unique role during pregnancy because of the rapid growth of cells, tissues, and organ systems in the developing fetus. Large maternal intake of EFAs is optimal. As modulators of vascular smooth-muscle tone and platelet aggregation, prostaglandins are involved in the development and clinical expression of preeclampsia. This condition is characterized by increased vasoconstriction and platelet aggregation, reduced uteroplacental blood flow, and preterm delivery. One study showed that gravidas receiving evening primrose oil plus fish oil had a significantly lower incidence of edema than did placebo recipients.23 Three cases of eclampsia occurred, all in the placebo group. Nurse-midwives have reported that evening primrose oil supplementation stimulates cervical ripening during labor.24 PGE^sub 1^ is also known to stimulate cervical ripening and hasten progression of labor.24 Although practitioners using this supplement reported no adverse effects, a retrospective study showed that evening primrose oil recipients, as compared with a control group that received no supplement, experienced an increased risk for premature rupture of the membranes, labor augmentation, and assisted vaginal delivery.25 Maternal levels of omega-3 fatty acids, especially DHA, decrease during pregnancy.26 For the fetus, a deficiency of EFAs (particularly EPA and DHA) may lead to a poorly developed CNS. EFA deficiency may also contribute to intrauterine growth restriction (IUGR), low birth weight, and slow brain growth. Supplementation with a daily complex of EFAs and fish oils during pregnancy will provide vital nutrients to compensate for the increased nutritional and metabolic demands throughout gestation. Fish oil supplementation has also been investigated for its effects on pregnancy duration, birth weight, IUGR, and pregnancy- induced hypertension (PIH).27,28 A regimen of 2.7 g daily of omega-3 fatty acids was compared with olive oil supplementation and with no supplement. Fish oil-supplemented pregnancies lasted longer (mean, 4 days) and infants in this group weighed more at birth (mean difference, 107 g). Fish oil also appeared to reduce the risk for preterm delivery in women who had experienced previous preterm delivery. Fish oil had no effect on IUGR or PIH. Although research shows that moderate EFA supplementation is beneficial and safe for pregnant women, large doses should probably be avoided. Also, caution should be exercised regarding increased intake of fish with a potentially high mercury content (eg, shark, swordfish, king mackerel, tilefish, tuna). Cardiovascular Disease CVD prevention and treatment are major health concerns for US women. Diets that are high in cholesterol and saturated fats contribute to an imbalance of saturated and unsaturated fatty acids, promoting premature coronary heart disease. Fish oils containing the omega-3 fatty acids EPA and DHA are associated with many cardioprotective effects, and have been found to lower CVD risk. Fish oils prevent blood clots, inhibit inflammation in vessel walls, promote vasodilation, and support a regular heart rhythm. They may also lower BP and triglyceride (TG) levels. Increasing omega-3 fatty acid intake may reduce the risk for atherosclerosis and blood clot formation, as well as lower BP. Many studies have shown that omega- 3s can also lower cholesterol and TG. These results are primarily associated with EPA- and DHA-- rich fish oils, but flaxseed oil can produce similar benefits because it contains ALA, an omega-3 fatty acid that is used to produce EPA. Fish oil intake also appears to protect against stroke in women. Researchers for the Nurses' Health Study followed 79,839 women aged 34 to 59 for 14 years.29 Free of documented CVD, cancer, diabetes, and hypercholesterolemia at baseline, these women completed a food questionnaire that included fish consumption. Compared with women who ate fish less than once per month, women who ate fish 1 to 3 times per month, 2 to 4 times per week, or 5 or more times per week all had a lower risk of stroke (the lattermost regimen led to the greatest risk reduction). Risk for thrombotic infarction was also significantly lower among women who ate fish 2 or more times per week. No association between fish or omega-3 fatty acid intake and risk of hemorrhagic stroke was noted. GLA has been shown to reduce CVD risk factors (it lowers BP and retards development of diet-induced atherosclerosis). Borage oil has been shown to augment control of vascular resistance, which can favorably alter BP.30 One study showed that black currant oil, also rich in GLA, significantly lowered diastolic BP in patients with borderline hypertension.31 Flaxseed and flax oil are also implemented in the prevention and treatment of CVD. Although the best evidence shows flax modestly improves lipid profile, it also has antiarrythmic, antiplatelet, antioxidant, and hypoglycemic potential. The majority of the evidence from 9 clinical trials suggests that flaxseeds or flaxseed powder can modestly reduce total cholesterol and LDL-C by 5% to 15%.32 Flaxseed oil given in large doses (60 mL) can modestly reduce total TG.33 CONCLUSION Physicians must educate their female patients about the fundamental role of EFAs in menstrual, breast, reproductive, and bone health. Good food sources of EFAs include high-quality vegetable oils such as Extra-virgin olive, flaxseed, pumpkin seed oils, and whole grains, and cold-water fish such as tuna, salmon, halibut, sardines, mackerel, and herring. EFAs are an important adjunct to a whole- foods diet, and can be particularly beneficial in women who are at higher risk for breast cancer and CVD. Optimal supplements include flaxseed oil (containing 50%-60% ALA), borage oil (20%-24% GLA), evening primrose oil (8%-10% GLA), black currant oil (15%-17% GLA), and fish oils (rich in EPA and DHA). Borage oil is nature's richest source of GLA, containing twice as much as evening primrose oil. Many reputable manufacturers offer " multi-EFA " combinations that include a blend of borage, EPO,black currant, sesame, fish, and flaxseed oils for convenient daily supplementation. Good nutrition encompasses the intake of good fats. Most women can benefit not only from reducing saturated fats in their diet but also from increasing the intake of good fats with daily EFA supplements. http://www.udoerasmus.com JoAnn Guest mrsjoguest Friendsforhea- http://www.geocities.com/mrsjoguest/AIM.html theaimcompanies " Health is not a Medical Issue " Quote Link to comment Share on other sites More sharing options...
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