Journal of Gerontological Nursing

The articles prior to January 2012 are part of the back file collection and are not available with a current paid subscription. To access the article, you may purchase it or purchase the complete back file collection here

CNE Article 

Polyunsaturated Fatty Acids: Immunomodulators in Older Adults

Frances Hardin-Fanning, PhD, RN; Gilbert A. Boissonneault, PhD, PA-C; Terry A. Lennie, PhD, RN, FAAN

Abstract

The immune system tends to become less efficient as people age, and nutrition plays a significant role in older adults’ immune responses. In particular, dietary fatty acids are precursors to important immune system components. Certain fatty acids, predominantly those that are polyunsaturated, also tend to decrease the risk of certain neurological diseases in older adults. This article describes the impact of dietary polyunsaturated fatty acids (PUFA) on older adults’ immune system and discusses the roles of age and immune status with regard to PUFA supplements.

Abstract

The immune system tends to become less efficient as people age, and nutrition plays a significant role in older adults’ immune responses. In particular, dietary fatty acids are precursors to important immune system components. Certain fatty acids, predominantly those that are polyunsaturated, also tend to decrease the risk of certain neurological diseases in older adults. This article describes the impact of dietary polyunsaturated fatty acids (PUFA) on older adults’ immune system and discusses the roles of age and immune status with regard to PUFA supplements.

Dr. Hardin-Fanning is Lecturer, Faculty Senator, and Faculty Advisor, Dr. Boissonneault is Professor and Interim Director, Division of Physician Assistant Studies, and Dr. Lennie is Associate Dean, PhD Studies, and Co-Director, RICH Heart Program, College of Nursing, University of Kentucky, Lexington, Kentucky.

The authors disclose that they have no significant financial interests in any product or class of products discussed directly or indirectly in this activity, including research support.

Address correspondence to Frances Hardin-Fanning, PhD, RN, Lecturer, Faculty Senator, and Faculty Advisor, University of Kentucky College of Nursing, 760 Rose Street, HSLC 418, Lexington, KY 40536; e-mail: Fdbowe2@uky.edu.

Received: April 19, 2010
Accepted: September 07, 2010
Posted Online: February 16, 2011

As people age, the immune system becomes less efficient at generating new immune responses, resulting in increased morbidity and mortality related to many chronic diseases. In addition, the immune system’s ability to regulate immune responses is reduced, increasing the likelihood of autoimmune diseases. Although these changes commonly occur as people age, it is unclear whether these immune changes are a natural part of the aging process or are largely influenced by other factors, such as lifelong nutritional habits.

Most chronic diseases, particularly autoimmune and other diseases commonly associated with aging, have a prominent inflammatory component that advances the negative effects of and susceptibility to many chronic illnesses. Nutrition plays a key role in the development of many chronic illnesses by contributing to the regulation of the inflammatory response, and dietary fatty acids are some of the most important contributors to this response. In particular, polyunsaturated fatty acids (PUFA) have significant effects on inflammation and immune responses and may serve as immunomodulators in chronic disease prevention. The purposes of this article are to describe the impact of dietary PUFA on the immune system and to discuss the roles of age and immune response status in recommending PUFA supplements.

Background

Most people consider dietary fats a source of energy that contributes to improved palatability of food and to the obesity epidemic in America. In reality, fats have many important biological functions within the cell membranes—as components in the synthesis of important biological mediators such as eicosanoids, which impact the immune system, and as regulatory signals in gene activation. Fatty acids fall into two broad categories: essential, which the body is unable to synthesize and therefore must obtain through dietary sources, and nonessential, which the body is able to synthesize.

The PUFA in the omega-6 and omega-3 families are the only essential fatty acids required by human beings. Omega-6 fatty acids include linoleic acid and its derivative arachidonic acid. The omega-6 PUFA linoleic acid is widely available in Western diets, derived primarily from plant oils such as corn, sunflower, and soybean oil. Its elongated derivative arachidonic acid is found in animal fats, and human beings also actively produce it from linoleic acid. The average intake of linoleic acid in the United States is 14.8 g per day (Moshfegh, Goldman, & Cleveland, 2005). Fatty acids of the omega-3 family include alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA).

The omega-3 PUFA ALA is derived primarily from tree nuts and certain plant oils, particularly flaxseed, soybean, and canola oils. It is the metabolic precursor for synthesis of EPA and DHA; however, its conversion to these forms is inefficient in human beings. For healthy adults to achieve an adequate level, more than 450 mg of EPA-DHA should be consumed daily. However, even under optimal conditions, only a maximum of 5% to 10% of ALA is converted to EPA and 2% to 5% to DHA (Wijendran & Hayes, 2004). Therefore, consuming EPA-DHA, which are primarily derived from marine sources, may be more effective in meeting the body’s requirements for these essential fatty acids than consuming ALA.

Commercial cold-water fish, such as salmon, mackerel, tuna, and trout, are richest in EPA-DHA, although other fish, particularly farmed fish, such as catfish, have significant amounts (e.g., 1.8 g in farmed Atlantic salmon, 0.15 g in farmed catfish) per 3 oz. serving (U.S. Department of Agriculture [USDA], 2005). To ensure people get enough of these essential fatty acids in their diets, adequate intakes (i.e., the amount of nutrient necessary to maintain health) have been established (Table 1).

Dietary Recommendations to Prevent Essential Polyunsaturated Fatty Acid Deficiencies

Table 1: Dietary Recommendations to Prevent Essential Polyunsaturated Fatty Acid Deficiencies

Fatty Acids and Immunity

Omega-3 and omega-6 PUFA have been shown to affect inflammation by modulating immune and other inflammatory responses in human beings. Because chronic stimulation of the immune system may contribute to risk for many chronic diseases (Green & Nicholson, 2008), it is important to recognize the role fatty acids play in regulating the inflammatory and immune responses.

Potent immunomodulating compounds, called eicosanoids (Figure), are derived from the omega-3 and omega-6 PUFA located in cell membranes (Wada et al., 2007). The eicosanoids, including prostaglandins, leukotrienes, thromboxanes, lipoxins, resolvins, and protectins (Table 2), can either contribute to or protect from the risk of many diseases, including cancer, cardiovascular disease (CVD), and pulmonary disease (Bäck, 2009; Greenhough et al., 2009; Haworth & Levy, 2007). Eicosanoid production is stimulated physiologically or pathologically by invading microorganisms, oxidants, and pharmacological agents such as antibiotic drugs (Brock & Peters-Golden, 2007). The omega-3 fatty acid DHA attenuates inflammation by inhibiting the cyclooxygenase (COX)-2 pathway of eicosanoid synthesis, which results in a marked decrease in the pro-inflammatory prostaglandins such as PGE2, an omega-6 derived eicosanoid that supports chronic disease (Khanapure, Garvey, Janero, & Letts, 2007; Massaro et al., 2006). In addition to direct inhibition of COX-2 activity, COX-2 products of omega-3 PUFA metabolism, such as PGE3, are typically less pro-inflammatory (Wada et al., 2007). Therefore, omega-6 PUFA may be thought to create a pro-inflammatory physiological state, while omega-3 PUFA reduce the risk of inflammatory-mediated chronic diseases (Massaro et al., 2006).

Dietary Polyunsaturated Fatty Acids Conversion, Food Sources, and Eicosanoids. Eicosanoids Are Formed Through the Cyclooxygenase (COX) and Lipoxygenase Pathways. Pro-Inflammatory Eicosanoids Thromboxane A2 (TXA2), Prostaglandin E2 (PGE2), and Leukotriene B4 (LTB4) Are Derived from Omega-6 Fatty Acids. Prostaglandin E1 (PGE1) Is Derived from Plant-Source Omega-6 Fatty Acid and Is Mostly an Anti-Inflammatory Eicosanoid. The Eicosanoids Derived from Plant or Marine Source Omega-3 Fatty Acids Tend to Be Anti-Inflammatory and Include Thromboxane A3 (TXA3), Leukotriene B5 (LTB5), Prostaglandin E3 (PGE3), Resolvins, and Neuroprotectin D1.

Figure. Dietary Polyunsaturated Fatty Acids Conversion, Food Sources, and Eicosanoids. Eicosanoids Are Formed Through the Cyclooxygenase (COX) and Lipoxygenase Pathways. Pro-Inflammatory Eicosanoids Thromboxane A2 (TXA2), Prostaglandin E2 (PGE2), and Leukotriene B4 (LTB4) Are Derived from Omega-6 Fatty Acids. Prostaglandin E1 (PGE1) Is Derived from Plant-Source Omega-6 Fatty Acid and Is Mostly an Anti-Inflammatory Eicosanoid. The Eicosanoids Derived from Plant or Marine Source Omega-3 Fatty Acids Tend to Be Anti-Inflammatory and Include Thromboxane A3 (TXA3), Leukotriene B5 (LTB5), Prostaglandin E3 (PGE3), Resolvins, and Neuroprotectin D1.

Polyunsaturated Fatty Acids Eicosanoids

Table 2: Polyunsaturated Fatty Acids Eicosanoids

Omega-6-derived prostaglandin PGE2 contributes to induction of fever (Calder, 2002) and induces Th2 cytokines, which prompt B cells to develop antibodies (Puthpongsiriporn & Scheideler, 2005). Secretion of inflammatory cytokines, such as tumor necrosis factor (TNF)-alpha, interleukin (IL)-1, and IL-6, is increased when dietary intake of omega-6 PUFA is significantly greater than omega-3 intake (Haynes & Swain, 2006). In contrast, omega-3 PUFA reduce the activity of natural killer (NK) cells and antigen presenting cells (Jeffery, Sanderson, Sherrington, Newsholme, & Calder, 1996). Increasing the combined intake of EPA and DHA reduces pro-inflammatory expression of arterial plaque-producing adhesion molecules, thereby impeding the process that causes endothelial dysfunction and increases the risk of CVD (Stenvinkel, 2001; Wijendran & Hayes, 2004). The fatty acids EPA and DHA are estimated to be nine times more potent in inhibiting inflammation than ALA (Calder, 2006).

The resolution of inflammation, once thought to be a passive process, is now recognized as an active event, and PUFA-derived eicosanoids are important contributors to this process. EPA can also be elongated to form DHA, and these two fatty acids are the precursors for novel anti-inflammatory compounds known as resolvins and protectins (Ariel & Serhan, 2007; Das, 2005; Levy et al., 2007). These omega-3-derived eicosanoids reduce synthesis of omega-6-derived eicosanoids, antagonize the effects of omega-6-derived eicosanoids, and enhance generation of inflammation-resolving mediators, such as the resolvins and protectins, thereby actively promoting the termination of inflammation and a return to homeostasis (Ariel & Serhan, 2007).

Considerations in Older Adults

Dietary fatty acids are thought to play key roles in the inflammatory-mediated effects on the neurological system in older adults. Both omega-6 and omega-3 PUFA have neuroprotective properties in the prevention of conditions such as Alzheimer’s disease (AD) and Parkinson’s disease by inhibiting inflammation (the main process involved in neuropathy), preventing neuronal death in global ischemia, stabilizing neuronal and myocyte electrical activity, and improving myelinogenesis (de Lau et al., 2005; Lauretani et al., 2007). Because more than 26 million individuals currently have AD (Brookmeyer, Johnson, Ziegler-Graham, & Arrighi, 2007) and effective treatments are lacking, risk identification and prevention are key in reducing the incidence of AD. Current evidence supports the role of omega-3 PUFA in the primary prevention, but not treatment, of AD and other dementias (Solfrizzi et al., 2010). However, the omega-6 arachidonic acid, in combination with DHA, improves cognitive dysfunction due to aging (Kotani et al., 2006). Dementia and depression are both inflammatory conditions, and the combination of omega-3 and omega-6 PUFA with folic acid suppresses this inflammation, thereby decreasing risk in older adults (Das, 2008; Morley & Banks, 2010).

Because of its physiological benefits, particularly in relation to neurological health, omega-6 PUFA intake may be just as crucial as omega-3 PUFA for disease prevention in older adults. Although increasing omega-3 intake and subsequently lowering the omega-6-to-omega-3 diet ratio results in CVD risk reduction, decreasing omega-6 intake does not appear to have the same effect and may actually increase rather than decrease CVD risk (Harris et al., 2009).

Another consideration is that there may be instances when a pro-inflammatory state and enhanced humoral immune response is desired; an example would be following vaccination. Older adults’ immune systems tend to be less efficient at responding to vaccines. Older adults produce more and have a greater sensitivity to PGE2, which suppresses some subsets of T-lymphocytes and NK cells, resulting in the need for higher levels of pro-inflammatory cytokines during antigenic challenge, such as following vaccination (Lesourd, 2006). In older adults, however, eicosanoids derived from arachidonic acid improve the immunological response to vaccine by enhancing T-cell functions (Kelley et al., 1997; Ridda et al., 2009). In particular, CD4+ helper T-cell function is enhanced, resulting in increased antibody production. COX-2-inhibiting drugs tend to suppress the humoral response to vaccination (Lupu et al., 2006), and it is logical to consider that nutritional sources of COX-2 inhibition may also suppress this response. Therefore, following vaccination, older adults may benefit from the pro-inflammatory eicosanoids derived from omega-6 fatty acids through an improved humoral response.

The American Heart Association (AHA) recommends omega-6 PUFA intake of 5% to 10% of energy (Harris et al., 2009), and although current evidence supports increasing omega-3 intake to lower the omega-6-to-omega-3 ratio, it does not support decreasing omega-6 intake to achieve the same ratio. The average 14.8 g per day intake of omega-6 in U.S. adults is within this range (Galli & Calder, 2009; Harris et al., 2009). Therefore, omega-6 supplements would only be advisable for individuals with dietary intake <5% of energy.

The basis for disease prevention in fatty acid biosynthesis involves the inflammatory and immune responses, which change over the life span. The immune system of older adults is influenced by dietary intake of fatty acids differently than those of younger to middle-aged adults. Incorporation of EPA and DHA omega-3 PUFA is more efficient in older adults than younger adults (Rees et al., 2006). Therefore, older adults’ immune system may be more sensitive to and benefit more from adequate levels of omega-6 and omega-3 fatty acids.

PUFA Intake Recommendations for Older Adults

A significant concern for clinicians should be the desirable ratio of omega-6 and omega-3 fatty acids that provides both cardiovascular and neurological protection. Although the ratio of omega-6 to omega-3 in current Western diets is 20 to 1, a ratio as close to 1 as possible is thought to be most desirable (Russo, 2009; Wertz, 2009). Evidence supports the health benefits of omega-6 and omega-3 PUFA, but the ideal ratio of omega-6 and omega-3 in the diet is currently under debate (Russo, 2009). While the current recommended intake of omega-3 PUFA helps protect against CVD, it is also important that older adults receive adequate omega-6 fatty acids. Therefore, the desirable ratio of omega-6 to omega-3 fatty acids should be maintained through adequate intake of omega-3 and not by decreasing omega-6 fatty acid intake.

Omega-3 fatty acids are associated with a significant risk reduction of cardiac death and total mortality following myocardial infarction by preventing arrhythmias (Russo, 2009). It has been suggested that omega-3 supplementation may be beneficial in regulating immunosenescence, which is responsible for late-life chronic disease, particularly CVD (Watson, Zibadi, Vazquez, & Larson, 2005). However, when administered in doses above 2 g per day, EPA and DHA can result in modest elevations of low-density lipoprotein cholesterol, and in individuals with CVD, doses above 4.8 g per day can result in increased levels of adhesion molecules involved in endothelial dysfunction and CVD (Johansen, Seljeflot, Høstmark, & Arnesen, 1999; Wijendran & Hayes, 2004).

Increasing omega-3 fatty acid intake through the use of fish oil capsules has become popular. The AHA recommends fish oil capsules only for those diagnosed with hypertriglyceridemia or CVD, and then only with careful monitoring by a practitioner (Kris-Etherton, Harris, & Appel, 2002). For individuals without heart disease, current recommendations are approximately 500 g per day, the equivalent of two servings of fatty fish weekly. Individuals with heart disease should consume double this amount (Lichtenstein et al., 2006). It is very unlikely that pro-inflammatory amounts of omega-3 fatty acids could be obtained solely through food sources, and greater risk of an inflammatory response would be from supplementation.

In older adults, higher doses of EPA can increase inflammation due to lipid oxidation and diminished antioxidant defenses (Cazzola et al., 2007). DHA in fish oil supplements has the potential to enhance the inflammatory response in individuals being treated for depression, a common condition in older adults (Maes, Mihaylova, Kubera, & Bosmans, 2007; Shaikh & Edidin, 2006). Activation of the inflammatory response system appears to play a significant role in depression, and DHA can potentiate this response by further inducing a Th1-type pro-inflammatory response (Maes et al., 2007).

While recent focus has been on omega-3 supplementation, the value of omega-6 fatty acids in neurological disease prevention is becoming apparent. It has been suggested that the use of sunflower oil, which is rich in omega-6 fatty acids, combined with DHA, may decrease neurological morbidity (Lauretani et al., 2007). The effects of unsaturated fatty acids on the neurological system are beginning to be examined. On the basis of recent evidence, currently recommended omega-6-to-omega-3 fatty acid ratios should be achieved by increasing omega-3 fatty acid intake. This approach to dietary fatty acids has the potential to protect both the cardiovascular system of healthy adults and afford protection to older adults with chronic diseases in which a decreased intake of omega-6 fatty acids appears to play a part.

Implications for Nursing Practice

Older adults are at higher risk for developing neurological disorders and more susceptible to viral and bacterial infections due, in part, to immunosenescence. Concerns have been raised that the influenza virus vaccine may not reduce mortality in the older population as much as previously thought, particularly in individuals older than 70 (Simonsen, Taylor, Viboud, Miller, & Jackson, 2007); therefore, interventions to enhance immune response to vaccination are needed. It can be difficult for older individuals to ascertain which diets and/or supplements are the best options for improving their overall health and immune systems. Nurses are in key positions to assess dietary intake, clarify concerns or questions, and recommend dietary changes that afford protection against immunosenescence and inflammatory-mediated chronic illnesses. In most cases, the addition of certain dietary fats and the omission of others are easily accomplished. Fats make food more palatable, and substituting some higher fat foods in the diet also improves satiety. A variety of foods containing PUFA can be incorporated into the diet (Tables 3 and 4). Information about other options is available from the USDA.

Food Sources of Omega-3

Table 3: Food Sources of Omega-3

Food Sources of Omega-6

Table 4: Food Sources of Omega-6

Summary

The essential PUFA omega-6 and omega-3 play key roles in CVD risk and in immune function. Omega-3 fatty acids decrease triglycerides, increase high-density lipoprotein cholesterol, and have anti-arrhythmic properties, thereby significantly decreasing the risk of cardiovascular morbidity and mortality (Russo, 2009). When replacing saturated fats in the diet, omega-6 fatty acids decrease low-density lipoprotein cholesterol levels and are associated with lower blood pressure and improved insulin resistance (Harris et al., 2009). In addition, PUFA omega-6, which is abundant in the U.S. diet, offers protection against age-related neurological disorders. An additional benefit of omega-6 intake is the activation of the immune system, particularly during periods when an enhanced humoral response is desired.

Because older adults are at higher risk for AD and Parkinson’s disease, and because omega-6 fatty acids show neuroprotective qualities, it is important that older adults receive adequate amounts of omega-6 either in their diet or through supplements. The AHA currently advises against decreasing omega-6 intake to achieve a lower ratio of omega-6 to omega-3. Although ratio is important, the absolute mass of each fatty acid needs to be considered. A ratio closer to 1, with equally small amounts of omega-6 and omega-3, will not result in the health benefits that are achieved when intake meets current recommendations (Galli & Calder, 2009). Therefore, older adults may benefit most by meeting current PUFA intake recommendations through increases in omega-3 intake, either through fish oil supplements or by eating high-fat fish at least twice weekly, and by ensuring adequate intake of dietary omega-6.

References

  • Ariel, A. & Serhan, C.N. (2007). Resolvins and protectins in the termination program of acute inflammation. Trends in Immunology, 28, 176–183. doi:10.1016/j.it.2007.02.007 [CrossRef]
  • Bäck, M. (2009). Leukotriene signaling in atherosclerosis and ischemia. Cardiovascular Drugs and Therapy, 23, 41–48. doi:10.1007/s10557-008-6140-9 [CrossRef]
  • Brock, T.G. & Peters-Golden, M. (2007). Activation and regulation of cellular eicosanoid biosynthesis. Scientific World Journal, 7, 1273–1284.
  • Brookmeyer, R., Johnson, E., Ziegler-Graham, K. & Arrighi, H.M. (2007). Forecasting the global burden of Alzheimer’s disease. Alzheimer’s & Dementia, 3, 186–191. doi:10.1016/j.jalz.2007.04.381 [CrossRef]
  • Calder, P.C. (2002). Dietary modification of inflammation with lipids. Proceedings of the Nutrition Society, 61, 345–358. doi:10.1079/PNS2002166 [CrossRef]
  • Calder, P.C. (2006). n-3 polyunsaturated fatty acids, inflammation, and inflammatory diseases. American Journal of Clinical Nutrition, 83(6 Suppl.), 1505S–1519S.
  • Cazzola, R., Russo-Volpe, S., Miles, E.A., Rees, D., Banerjee, T., Roynette, C.E. & Cestaro, B.,… (2007). Age- and dose-dependent effects of an eicosapentaenoic acid-rich oil on cardiovascular risk factors in healthy male subjects. Atherosclerosis, 193, 159–167. doi:10.1016/j.atherosclerosis.2006.06.008 [CrossRef]
  • Das, U.N. (2005). COX-2 inhibitors and metabolism of essential fatty acids. Medical Science Monitor, 11, RA233–RA237.
  • Das, U.N. (2008). Folic acid and polyunsaturated fatty acids improve cognitive function and prevent depression, dementia and Alzheimer’s disease–But how and why?Prostaglandins, Leukotrienes, and Essential Fatty Acids, 78 (1), 11–19. doi:10.1016/j.plefa.2007.10.006 [CrossRef]
  • de Lau, L.M., Bornebroek, M., Witteman, J.C., Hofman, A., Koudstaal, P.J. & Breteler, M.M. (2005). Dietary fatty acids and the risk of Parkinson disease: The Rotterdam Study. Neurology, 64, 2040–2045. doi:10.1212/01.WNL.0000166038.67153.9F [CrossRef]
  • Fischer, S. & Weber, P.C. (1983). Thromboxane A3 (TXA3) is formed in human platelets after dietary eicosapentaenoic acid (C20:5 omega 3). Biochemical and Biophysical Research Communications, 116, 1091–1099. doi:10.1016/S0006-291X(83)80254-X [CrossRef]
  • Galli, C. & Calder, P.C. (2009). Effects of fat and fatty acid intake on inflammatory and immune responses: A critical review. Annals of Nutrition & Metabolism, 5, 123–139. doi:10.1159/000228999 [CrossRef]
  • Gebauer, S.K., Psota, T.L., Harris, W.S. & Kris-Etherton, P.M. (2006). n-3 fatty acid dietary recommendations and food sources to achieve essentiality and cardiovascular benefits. American Journal of Clinical Nutrition, 83(6 Suppl.), 1526S–1535S.
  • Green, C.R. & Nicholson, L.F. (2008). Interrupting the inflammatory cycle in chronic diseases–Do gap junctions provide the answer?Cell Biology International, 32, 1578–1583. doi:10.1016/j.cellbi.2008.09.006 [CrossRef]
  • Greenhough, A., Smartt, H.J.M., Moore, A.E., Roberts, H.R., Williams, A.C., Paraskeva, C. & Kaidi, A. (2009). The COX-2/PGE2 pathway: Key roles in the hallmarks of cancer and adaptation to the tumour microenvironment. Carcinogenesis, 30, 377–386. doi:10.1093/carcin/bgp014 [CrossRef]
  • Harris, W.S., Mozaffarian, D., Rimm, E., Kris-Etherton, P., Rudel, L.L., Appel, L.J. & Sacks, F.,… (2009). Omega-6 fatty acids and risk for cardiovascular disease: A science advisory from the American Heart Association Nutrition Subcommittee of the Council on Nutrition, Physical Activity, and Metabolism; Council on Cardiovascular Nursing; and Council on Epidemiology and Prevention. Circulation, 119. Retrieved from http://circ.ahajournals.org/cgi/reprint/CIRCULATIONAHA.108.191627v1 doi:10.1161/CIRCULATIONAHA.108.191627 [CrossRef]
  • Haworth, O. & Levy, B.D. (2007). Endogenous lipid mediators in the resolution of airway inflammation. European Respiratory Journal, 30, 980–992. doi:10.1183/09031936.00005807 [CrossRef]
  • Haynes, L. & Swain, S.L. (2006). Why aging T cells fail: Implications for vaccination. Immunity, 24, 663–666. doi:10.1016/j.immuni.2006.06.003 [CrossRef]
  • Jeffery, N.M., Sanderson, P., Sherrington, E.J., Newsholme, E.A. & Calder, P.C. (1996). The ratio of n-6 to n-3 polyunsaturated fatty acids in the rat diet alters serum lipid levels and lymphocyte functions. Lipids, 31, 737–745. doi:10.1007/BF02522890 [CrossRef]
  • Johansen, O., Seljeflot, I., Høstmark, A.T. & Arnesen, H. (1999). The effect of supplementation with omega-3 fatty acids on soluble markers of endothelial function in patients with coronary artery disease. Arteriosclerosis, Thrombosis, and Vascular Biology, 19, 1681–1686.
  • Kelley, D.S., Taylor, P.C., Nelson, G.J., Schmidt, P.C., Mackey, B.E. & Kyle, D. (1997). Effects of dietary arachidonic acid on human immune response. Lipids, 32, 449–456. doi:10.1007/s11745-997-0059-3 [CrossRef]
  • Khanapure, S.P., Garvey, D.S., Janero, D.R. & Letts, L.G. (2007). Eicosanoids in inflammation: Biosynthesis, pharmacology, and therapeutic frontiers. Current Topics in Medicinal Chemistry, 7, 311–340. doi:10.2174/156802607779941314 [CrossRef]
  • Kotani, S., Sakaguchi, E., Warashina, S., Matsukawa, N., Ishikura, Y., Kiso, Y. & Yamashima, T.,… (2006). Dietary supplementation of arachidonic and docosahexaenoic acids improves cognitive dysfunction. Neuroscience Research, 56, 159–164. doi:10.1016/j.neures.2006.06.010 [CrossRef]
  • Kris-Etherton, P.M., Harris, W.S. & Appel, L.J. (2002). Fish consumption, fish oil, omega-3 fatty acids, and cardiovascular disease. Circulation, 106. Retrieved from http://circ.ahajournals.org/cgi/reprint/106/21/2747 doi:10.1161/01.CIR.0000038493.65177.94 [CrossRef]
  • Lauretani, F., Bandinelli, S., Bartali, B., Cherubini, A., Iorio, A.D., Blè, A. & Ferrucci, L.,… (2007). Omega-6 and omega-3 fatty acids predict accelerated decline of peripheral nerve function in older persons. European Journal of Neurology, 14, 801–808. doi:10.1111/j.1468-1331.2007.01860.x [CrossRef]
  • Lesourd, B. (2006). Nutritional factors and immunological ageing. Proceedings of the Nutrition Society, 65, 319–325. doi:10.1079/PNS2006507 [CrossRef]
  • Levy, B.D., Kohli, P., Gotlinger, K., Haworth, O., Hong, S., Kazani, S. & Serhan, C.N.,… (2007). Protectin D1 is generated in asthma and dampens airway inflammation and hyperresponsiveness. Journal of Immunology, 178, 496–502.
  • Lichtenstein, A.H., Appel, L.J., Brands, M., Carnethon, M., Daniels, S., Franch, H.A. & Wylie-Rosett, J.,… (2006). Diet and lifestyle recommendations revision 2006: A scientific statement from the American Heart Association Nutrition Committee. Circulation, 114. Retrieved from http://circ.ahajournals.org/cgi/reprint/CIRCULATIONAHA.106.176158v1 doi:10.1161/CIRCULATIONAHA.106.176158 [CrossRef]
  • Lukiw, W.J., Cui, J.-G., Marcheselli, V.L., Bodker, M., Botkjaer, A., Gotlinger, K. & Bazan, N.G.,… (2005). A role for docosahexaenoic acid-derived neuroprotectin D1 in neural cell survival and Alzheimer disease. Journal of Clinical Investigation, 115, 2774–2783. doi:10.1172/JCI25420 [CrossRef]
  • Lupu, A.R., Cremer, L., Durbacă, S., Călugaru, A., Herold, A., Kerek, F. & Radu, D.L.,… (2006). COX-2 inhibitors can down-regulate in vivo antibody response against T-dependent antigens. Roumanian Archives of Microbiology and Immunology, 65(1–2), 59–65.
  • Maes, M., Mihaylova, I., Kubera, M. & Bosmans, E. (2007). Why fish oils may not always be adequate treatments for depression and other inflammatory illnesses: Docosahexaenoic acid, an omega-3 polyunsaturated fatty acid, induces a Th-1-like immune response. Neuroendocrinology Letters, 28, 875–880.
  • Massaro, M., Habib, A., Lubrano, L., Del Turco, S., Lazzerini, G., Bourcier, T. & De Caterina, R.,… (2006). The omega-3 fatty acid docosahexaenoate attenuates endothelial cyclooxygenase-2 induction through both NADP(H) oxidase and PCK epsilon inhibition. Proceedings of the National Academy of Sciences of the United States of America, 103, 15184–15189. doi:10.1073/pnas.0510086103 [CrossRef]
  • Morley, J.E. & Banks, W.A. (2010). Lipids and cognition. Journal of Alzheimer’s Disease, 20, 737–747.
  • Moshfegh, A., Goldman, J. & Cleveland, L. (2005). What we eat in America, NHANES 2001–2002: Usual nutrient intakes from food compared to dietary reference intakes. Retrieved from the U.S. Department of Agriculture website: http://www.ars.usda.gov/SP2UserFiles/Place/12355000/pdf/0102/usualintaketables2001-02.pdf
  • Puthpongsiriporn, U. & Scheideler, S.E. (2005). Effects of dietary ratio of linoleic to linolenic acid on performance, antibody production, and in vitro lymphocyte proliferation in two strains of leghorn pullet chicks. Poultry Science, 84, 846–857.
  • Rees, D., Miles, E.A., Banerjee, T., Wells, S.J., Roynette, C.A., Wahle, K.W. & Calder, P.C. (2006). Dose-related effects of eicosapentaenoic acid on innate immune function in healthy humans: A comparison of young and older men. American Journal of Clinical Nutrition, 83, 331–342.
  • Ridda, I., Macintyre, C.R., Lindley, R., Gao, Z., Sullivan, J.S., Yuan, F.F. & McIntyre, P.B. (2009). Immunological responses to pneumococcal vaccine in frail older people. Vaccine, 27, 1628–1636. doi:10.1016/j.vaccine.2008.11.098 [CrossRef]
  • Russo, G.L. (2009). Dietary n-6 and n-3 polyunsaturated fatty acids: From biochemistry to clinical implications in cardiovascular prevention. Biochemical Pharmacology, 77, 937–946. doi:10.1016/j.bcp.2008.10.020 [CrossRef]
  • Shaikh, S.R. & Edidin, M. (2006). Polyunsaturated fatty acids, membrane organization, T cells, and antigen presentation. American Journal of Clinical Nutrition, 84, 1277–1289.
  • Simonsen, L., Taylor, R.J., Viboud, C., Miller, M.A. & Jackson, L.A. (2007). Mortality benefits of influenza vaccination in elderly people: An ongoing controversy. Lancet Infectious Diseases, 7, 658–666. doi:10.1016/S1473-3099(07)70236-0 [CrossRef]
  • Simopoulos, A.P. (2002). Omega-3 fatty acids in inflammation and autoimmune diseases. Journal of the American College of Nutrition, 21, 495–505.
  • Solfrizzi, V., Frisardi, V., Capurso, C., D’Introno, A., Collacicco, A.M., Vendemiale, G. & Panza, F.,… (2010). Dietary fatty acids in dementia and predementia syndromes: Epidemiological evidence and possible underlying mechanisms. Ageing Research Reviews, 9, 184–199. doi:10.1016/j.arr.2009.07.005 [CrossRef]
  • Stenvinkel, P. (2001). Endothelial dysfunction and inflammation–Is there a link?Nephrology, Dialysis, Transplantation, 16, 1968–1971. doi:10.1093/ndt/16.10.1968 [CrossRef]
  • U.S. Department of Agriculture. (2005). Addendum A: EPA and DHA content of fish species. In Appendix G2: Original food guide pyramid patterns and description of USDA analyses. Retrieved from the U.S. Department of Health and Human Services website: http://www.health.gov/dietary-guidelines/dga2005/report/html/table_g2_adda2.htm
  • U.S. Department of Agriculture. (2010). What’s in the foods you eat [Database]. Retrieved from http://www.ars.usda.gov/Services/docs.htm?docid=17032
  • Wada, M., DeLong, C.J., Hong, Y.H., Rieke, C.J., Song, I., Sidhu, R.S. & Smith, W.L.,… (2007). Enzymes and receptors of prostaglandin pathways with arachidonic acid-derived versus eicosapentaenoic acid-derived substrates and products. Journal of Biological Chemistry, 282, 22254–22266. doi:10.1074/jbc.M703169200 [CrossRef]
  • Watson, R.R., Zibadi, S., Vazquez, R. & Larson, D. (2005). Nutritional regulation of immunosenescence for heart health. Journal of Nutritional Biochemistry, 16, 85–87. doi:10.1016/j.jnutbio.2004.10.001 [CrossRef]
  • Wertz, P.W. (2009). Essential fatty acids and dietary stress. Toxicology and Industrial Health, 25, 279–283. doi:10.1177/0748233709103035 [CrossRef]
  • Wijendran, V. & Hayes, K.C. (2004). Dietary n-6 and n-3 fatty acid balance and cardiovascular health. Annual Review of Nutrition, 24, 597–615. doi:10.1146/annurev.nutr.24.012003.132106 [CrossRef]

Dietary Recommendations to Prevent Essential Polyunsaturated Fatty Acid Deficiencies

Fatty Acid Adequate Intake
Alpha-linolenic acid (omega-3) Men: 1.6 g per day Women: 1.1 g per day
Eicosapentaenoic acid and docosahexaenoic acid (omega-3) 450 to 500 mg per day
Linoleic acid (omega-6) Men: 17 g per day Women: 12 g per day

Polyunsaturated Fatty Acids Eicosanoids

Omega-6 Eicosanoids Inflammatory Response Functions
Prostaglandin E1 Decreases platelet aggregation, increases vasodilation
Prostaglandin E2 Induces fever response, serves as a vasodilator, mediates vascular permeability and edema
Thromboxane A2 Increases platelet aggregation, increases vasodilation
Leukotriene B4 Increases neutrophil aggregation, increases white blood cell chemotaxis, increases vascular permeability
Lipoxins Decreases leukocyte migration, decreases expression of adhesion molecules
Omega-3 Eicosanoids
Prostaglandin E3 Decreases platelet aggregation, decreases vasodilation
Thromboxane A3 Decreases platelet aggregation
Leukotriene B5 Decreases neutrophil aggregation, decreases white blood cell chemotaxis, decreases vascular permeability
Resolvins (D series DHA, E series EPA) Regulate polymorphonuclear infiltration and interleukin-12 production, reduce T-cell-mediated inflammatory response and actively resolve inflammatory response
Neuroprotectin D1 (DHA) Inhibits brain cell apoptosis

Food Sources of Omega-3

Food (Serving) Kcals ALA (grams) EPA (grams) DHA (grams)
Salmon, baked or broiled (1 cup) 230 0.16 0.69 0.97
Salmon, baked or broiled, 1 medium filet (276 g) 466 0.33 1.4 1.96
Halibut, 1 filet (130 g) 173 0.11 0.14 0.16
Tuna, canned (13 oz.) 636 0.24 0.09 0.32
Tuna, 1 medium filet (340 g) 520 0.3 0.15 0.72
Tuna, steak (149 g) 228 0.13 0.06 0.31
Scallops, breaded/fried (1 cup) 291 0.23 0.12 0.14
Shrimp, baked or broiled (10 large) 90 0.06 0.19 0.16
Shrimp, baked or broiled (10 medium) 80 0.05 0.16 0.13
Shrimp, breaded/battered, fried (10 large) 420 0.3 0.38 0.33
Trout, baked or broiled, 1 medium filet (163 g) 306 0.23 0.49 1.27
Trout, breaded/battered, fried, 1 medium filet (195 g) 525 0.57 0.39 1.01
Canola, soybean, or sunflower oil (1 Tbsp.) 120 0.99
Flaxseed oil (1 Tbsp.) 120 7.25
Broccoli, raw (1 cup) 30 0.02
Spinach, raw (1 cup) 7 0.41
Winter squash, ½ acorn (156 g) 58 0.14
Kidney beans, dry, cooked, no fat (1 cup) 217 0.29
Walnuts, 14 halves (28 g) 186 2.58
Olive oil (1 Tbsp.) 119 0.10
Corn oil, stick margarine (1 Tbsp.) 102 0.29
Milk, whole (1 cup) 146 0.18
Beef, sirloin steak, lean (265 g) 628 0.29
Pork chop, lean, breaded/fried (4 oz.) 292 0.36

Food Sources of Omega-6

Food (Serving) Kcals LA (grams) AA (grams)
Canola, soybean, or sunflower oil (1 Tbsp.) 120 4.96
Flaxseed oil (1 Tbsp.) 120 1.73
Walnuts, 14 halves (28 g) 186 10.8
Olive oil (1 Tbsp.) 119 1.32
Corn oil, stick margarine (1 Tbsp.) 102 3.16
Peanut butter (1 Tbsp.) 94 2.25
Kidney beans, dry, cooked, no fat (1 cup) 217 0.18
Raisin, date, and pecan whole grain cereal (1 cup) 305 2.33
Oatmeal, instant, cooked (1 cup) 143 0.83
Milk, whole (1 cup) 146 0.29
Beef, sirloin steak, lean (265 g) 628 0.93 0.09
Pork chop, lean, breaded/fried (4 oz.) 292 3.48 0.04
Chicken breast, baked or roasted, no skin (126 g) 207 0.74 0.08

Instructions

2.1 contact hours will be awarded for this activity. A contact hour is 60 minutes of instruction. This is a Learner-Paced Program. Vindico Medical Education does not require submission of quiz answers. A contact hour certificate will be awarded 4 to 6 weeks upon receipt of your completed Registration Form, including the Evaluation portion. To obtain contact hours:

  1. Read the article “Polyunsaturated Fatty Acids: Immunomodulators in Older Adults” by Frances Hardin-Fanning, PhD, RN; Gilbert A. Boissonneault, PhD, PA-C; and Terry A. Lennie, PhD, RN, FAAN on pages 20–28, carefully noting the tables and other illustrative materials that are provided to enhance your knowledge and understanding of the content.

  2. Read each question and record your answers. After completing all questions, compare your answers to those provided at the end of the quiz.

  3. Type or print your full name, address, and date of birth in the spaces provided on the registration form.

  4. Indicate the total time spent on the activity (reading article and completing quiz). Forms and quizzes cannot be processed if this section is incomplete. All participants are required by the accreditation agency to attest to the time spent completing the activity.

  5. Forward the completed form with your check or money order for $15 made payable to JGN-CNE. All payments must be made in U.S. dollars and checks must be drawn on U.S. banks. CNE Registration Forms must be received no later than May 31, 2013.

This activity is co-provided by Vindico Medical Education and the Journal of Gerontological Nursing. Vindico Medical Education is an approved provider of continuing nursing education by New Jersey State Nurses Association, an accredited approver, by the American Nurses Credentialing Center’s Commission on Accreditation, P#188-6/09-12.

Activity Objectives

  1. Identify the role of polyunsaturated fatty acids (PUFAs) in immunomodulation.

  2. Identify dietary sources of omega-3 and omega-6 PUFAs.

  3. Describe the neurological benefits of PUFAs.

  4. Discuss recommended intake and sources of PUFAs for older adults.

  5. Discuss implications for nursing practice.

Author Disclosure Statement

Dr. Hardin-Fanning, Dr. Boissonneault, and Dr. Lennie disclose that they have no significant financial interests in any product or class of products discussed directly or indirectly in this activity, including research support.

Commercial Support Statement

All authors and planners have agreed that this activity will be free of commercial bias. There is no commercial support for this activity. There is no non-commercial support for this activity.

Keypoints

Hardin-Fanning, F., Boissonneault, G.A. & Lennie, T.A. (2011). Polyunsaturated Fatty Acids: Immunomodulators in Older Adults. Journal of Gerontological Nursing, 37(5), 20–28.

  1. Most chronic diseases commonly associated with aging have a prominent inflammatory component that advances the negative effects of and susceptibility to many chronic illnesses.

  2. Omega-6 and omega-3 polyunsaturated fatty acids have neuroprotective properties in the prevention of conditions such as Alzheimer’s disease and Parkinson’s disease, as well as properties that protect against cardiovascular disease.

  3. Polyunsaturated fatty acids have significant effects on inflammation and immune responses and may serve as immunomodulators in the prevention of chronic disease in older adults.

Authors

Dr. Hardin-Fanning is Lecturer, Faculty Senator, and Faculty Advisor, Dr. Boissonneault is Professor and Interim Director, Division of Physician Assistant Studies, and Dr. Lennie is Associate Dean, PhD Studies, and Co-Director, RICH Heart Program, College of Nursing, University of Kentucky, Lexington, Kentucky.

The authors disclose that they have no significant financial interests in any product or class of products discussed directly or indirectly in this activity, including research support.

Address correspondence to Frances Hardin-Fanning, PhD, RN, Lecturer, Faculty Senator, and Faculty Advisor, University of Kentucky College of Nursing, 760 Rose Street, HSLC 418, Lexington, KY 40536; e-mail: .Fdbowe2@uky.edu

10.3928/00989134-20110201-01

Sign up to receive

Journal E-contents