TY - JOUR
AU - MD, Joseph R. Hibbeln,
AB - ABSTRACT Research indicates that dietary omega-3 and omega-6 polyunsaturated fatty acids (PUFAs) are important in reducing the risk of mental illness. We used the DoD Survey of Health Related Behaviors among Active Duty Military Personnel (HRBS) to assess current military dietary patterns and meal locations. We used the Lands Equation to model PUFAs in a sample Garrison diet and the nutritional impact of substitution of foods higher in omega-3 PUFAs and lower in omega-6 PUFAs on tissue composition. The military diet was very poor quality compared to 2010 Healthy People Guidelines. A representative Garrison diet does not meet our estimated healthy n-3 HUFA intake at 3.5 g/d, corresponding with a tissue composition of 60% n-3 in HUFA (i.e., 40% n-6 in HUFA). Substitution of n-3 rich eggs, poultry, pork and other food commodities, combined with use on low linoleic acid oils, may contribute significantly to attaining healthier n-6/n-3 proportions in the tissue. INTRODUCTION Highly unsaturated omega-3 (n-3) fatty acids (n-3 HUFAs) have been demonstrated to have health benefits such as cardiovascular protection, prevention from adverse surgical consequences, and reduction of risk for mental illnesses.1 Several international organizations have issued recommendations for dietary intakes of n-3 HUFAs. However, neither the most recent Dietary Guidelines for Americans nor the national Dietary Reference Intakes from the Institute of Medicine provide recommendations for omega-3 fatty acids.2,3 The U.S. military develops nutrient intake guidance based on the IOM civilian recommendations called the Military Dietary Reference Intakes (MDRIs). At present, the MRDIs do not address omega-3 or omega-6 fatty acids. Dietary deficiencies of nutrients critical for optimal brain function, such as n-3 HUFAS, may be a significant risk factor for adverse psychiatric outcomes such as depression and suicide.4 Meta-analyses of clinical treatment trials of n-3 HUFAs with diagnosed depression among adults indicate efficacy in reduction of depression symptoms, which is comparable to that of antidepressant medications.1,5,6 After more than a decade of war, suicide rates among active duty U.S. military Personnel are at a record high. According to figures released by the armed services, the U.S. Military has lost more troops to suicide than to combat in Iraq and Afghanistan during both 2009 and 2010.7 Recently, Lewis et al8 reported that low n-3 HUFA status increased the risk of deaths in a comparison of 800 active duty suicides to matched controls. Several challenges exist in elevating n-3 fatty acid intake among the U.S. military. First, active duty military Personnel are not included in the national Centers for Disease Control and Prevention—based, surveillance programs such as the National Health and Nutrition Examination Survey and the National Health Interview Survey from which the United States obtains most national-level diet, nutrition, and health outcome information for the U.S. population.9 As a result, little is known about the diet and food choices among the U.S. active duty Personnel as a whole. Second, military Personnel depending upon location may have variable access to a diversity of food. However, in all but active combat situations, they have access to food through military dining facilities, or military-base canteens, snack bars, and contractor-food providers. Third, while n-3 HUFA dietary supplements provide a plausible alternative, compliance is often an issue with dietary supplements in capsule form. Finally, there may be variability in the historically high amounts of omega-6 fats in the background diets, which necessitate variable levels of omega-3s to be consumed to achieve optimal tissue levels. To identify dietary intake and location of meals, we referenced data analyzed by one of us (bpm) as part of the 2005 Department of Defense Survey of Health Related Behaviors among Active Duty Military Personnel (HRBS) final report.10 The HRBS is a stratified cluster sample of worldwide military installations including the Army, Air Force, Navy, and Marines. The HRBS began in 1980 with the overall focus on substance use with an emphasis on worldwide active duty Personnel's self-reported use of alcohol, illicit drugs, tobacco, related health effects, and demographics of the anonymous respondents. The 2005 survey included questions on substance use and also addressed selected Healthy People 2010 objectives11 including diet and physical activity. With the 2005 HRBS final report, data was available on the dietary patterns of active duty Personnel worldwide for the first time. We used this data to understand the basic composition and location of Personnel eating patterns within the context of assessing the potential to improve the fatty acid composition of military diets through menu food item substitution. In general, dietary patterns of active duty Personnel were very poor compared with the 2010 Healthy People Guidelines (HPG).12 The HPG recommended 2 or more servings of fruit per day and 3 or more servings of vegetables per day. Less than 10% of active duty Personnel reported eating 3 or more servings of fruits and vegetables per day.11 For whole grains, the HPG recommended three 1-oz servings per day and 3 cups per day of fat-free or low-fat daily milk or equivalent products.11 Less than 12% of military Personnel met the recommendations for the intake of whole grains and low-fat milk products. Of particular relevance to this study, almost 50% of Personnel reported eating fast food three or more times per week across all Service branches. Only around 20% of Personnel reported eating lean protein, including fish, three or more times per week. Therefore, fish as a source of omega-3 fatty acids is unlikely to be a successful omega-3 delivery vehicle for by active duty Personnel. Data on the location of breakfast, lunch, and dinner for the four branches of military Personnel were collected as part of the 2005 HRBS and included in the final report.10 Forty-three percent of Personnel reported that they ate breakfast at home or brought breakfast from home and another 42% said that they typically skipped breakfast altogether. Thirty percent said they ate dinner from take-out restaurants, whereas 63% ate dinner at home or meals from home. Twenty-seven percent of military Personnel indicated that they ate lunch in military dining facilities or took lunch out from military dining facilities. Location of lunch varied little across the Services with approximately 43% saying they brought lunch from home and 29% reporting obtaining lunch in restaurants or takeout. These data provided the context for our modeling study showing that the sources of n-3 HUFAs appeared to be low in military diets and that the most opportune military meal setting to make potential meal item substitutions in garrison settings would be at lunch. The purpose of our study was to evaluate the feasibility of using the military-base dining facilities to improve intake and increase blood levels of n-3 HUFAs through direct substitution of existing menu items with the same items with higher omega-3 and lower omega-6 fatty acid content. If substitution of foods enriched in n-3 and low in n-6 into the current diet can elevate tissue composition of n-3 HUFAs, potential exists for improving the overall health status of military populations without the need for use of dietary supplements. Among such foods, n-3-enriched eggs are already available commercially, while other enriched commodities such as pork and chicken are not yet available to consumers, but are currently being tested in pilot studies. Key to such a substitution experiment would be the knowledge of when and where military Personnel collectively eat so that food substitution efforts would have maximal effect. Our specific goals were to estimate the linoleic acid (LA), alpha-linolenic acid (ALA), n-6 HUFA, and n-3 HUFA content and the resulting tissue compositions comparing a regular diet to a diet with improved fatty acid ingredient compositions, to determine if such a substitution would be feasible and meaningful in a military Garrison setting. MATERIALS AND METHODS Sample Garrison Menus and Swapping Modeling We partnered with the U.S. Garrison at Okinawa to obtain information about menu items that we could use in our theoretical model of fatty acid item swapping. A typical U.S. Garrison diet is divided into three primary food lines: a mainline menu, a fast-food line, and a line for specialty bars. Only the mainline and fast-food line menus were analyzed in this study. In our Okinawa sample, the mainline menu consisted of 28 daily recipes repeated 1 cycle per month and provided cafeteria-style meals with hot and cold sides. The fast-food menu consisted of 1 daily menu repeated 28 cycles per month and provided typical fast-food-style offerings and grab-and-go foods, including condiments and drinks. A summary of these example Garrison food offerings is given in Table I. Recipes for the above food offerings and forecast servings data were provided by Lt. Col. Carlos Sanabria, Department of Defense Food Service and Sustenance Programs. TABLE I Summary of Garrison Total Offerings for Okinawa for 1 Month (February 2009) Food Source  Calories/Cycle  Servings/Cycle  Cycles/Month  Calories/Month  Servings/Month  Mainline  15,774,387  90,611  1  15,774,387  90,611  Fast foods (Food Items)  1,111,309  7,843  28  31,116,652  219,604  Fast foods (Including Fry Oil)  1,258,336  7,843  28  35,233,413  219,604  Specialty Bars  792,180  3,485  4  3,168,720  13,940  Food Source  Calories/Cycle  Servings/Cycle  Cycles/Month  Calories/Month  Servings/Month  Mainline  15,774,387  90,611  1  15,774,387  90,611  Fast foods (Food Items)  1,111,309  7,843  28  31,116,652  219,604  Fast foods (Including Fry Oil)  1,258,336  7,843  28  35,233,413  219,604  Specialty Bars  792,180  3,485  4  3,168,720  13,940  View Large TABLE I Summary of Garrison Total Offerings for Okinawa for 1 Month (February 2009) Food Source  Calories/Cycle  Servings/Cycle  Cycles/Month  Calories/Month  Servings/Month  Mainline  15,774,387  90,611  1  15,774,387  90,611  Fast foods (Food Items)  1,111,309  7,843  28  31,116,652  219,604  Fast foods (Including Fry Oil)  1,258,336  7,843  28  35,233,413  219,604  Specialty Bars  792,180  3,485  4  3,168,720  13,940  Food Source  Calories/Cycle  Servings/Cycle  Cycles/Month  Calories/Month  Servings/Month  Mainline  15,774,387  90,611  1  15,774,387  90,611  Fast foods (Food Items)  1,111,309  7,843  28  31,116,652  219,604  Fast foods (Including Fry Oil)  1,258,336  7,843  28  35,233,413  219,604  Specialty Bars  792,180  3,485  4  3,168,720  13,940  View Large Estimation of Fatty Acid Composition of Foods in Garrison Menu Lines An overview of the analysis data path is shown in Figure 1. The ingredient composition of 507 recipes were entered into the Keep It Managed (KIM) II12 U.S. Department of Agriculture (USDA) food composition database (Fig. 2), which links to and references the USDA National Nutrient Database for Standard Reference.13 The total food energy content (kcal per serving) and fatty acid content (mg per serving) of the following 4 categories of essential fatty acids was obtained from the KIM II output: (1) 18-carbon n-3 polyunsaturated fatty acid (PUFA) (ALA), (2) 18-carbon n-6 PUFA (LA), (3) 20- and 22-carbon n-3 HUFAs (eicosapentaenoic acid [EPA], docosapentaenoic acid [DPA] n-3, docosahexaenoic acid [DHA]), and (4) 20- and 22-carbon n-6 HUFAs (AA and DPA n-6). FIGURE 1 View largeDownload slide Study overview and outline of data path from provided recipe to tissue composition predictions. FIGURE 1 View largeDownload slide Study overview and outline of data path from provided recipe to tissue composition predictions. FIGURE 2 View largeDownload slide Sausage, egg, and cheese croissant. (A) Input of ingredient composition of recipe into KIM II database. (B) Output of KIM II displaying essential fatty acid content per serving of recipe. FIGURE 2 View largeDownload slide Sausage, egg, and cheese croissant. (A) Input of ingredient composition of recipe into KIM II database. (B) Output of KIM II displaying essential fatty acid content per serving of recipe. Forecast correction adjusts for the different distribution of foods expected to be consumed in a location, for example, based on the survey data and information from Okinawa, more cheese burgers than fish sandwiches were forecast to be consumed. Forecast correction was performed for total fatty acid intake and total calories consumed by a garrison population over the 28-day sampling period. The fatty acid output (mg per serving) and food energy content (kcal per serving) per recipe serving were entered into a productions worksheet (C. Sanabria, personal communication), which details the quantity of each menu offering produced each day. The quantity of each food item produced daily is determined by previous consumption patterns in the example garrison. Thus, the productions worksheet was used to obtain a “forecasted” menu that estimated the quantity of each menu item that would actually be consumed by the garrison over the sampling period. This method of estimating total garrison consumption involves an inherent limitation in that not all food that is produced may be consumed, with some food being discarded as waste and with individuals selecting only subsets of available foods. Forecast correction was performed by multiplying both the fatty acid output (mg per serving) and the food energy content (kcal per serving) of each recipe by the number of servings forecasted for consumption during the sampling period, giving (1) total ALA, LA, n-3 HUFAs, and n-6 HUFAs intake (g per garrison per 28 days) and (2) total calorie intake (kcal per garrison per 28 days). Forecast correction was performed separately for each respective food line. The forecast-corrected fatty acid and food energy content of 507 recipes were then summed. A detailed description of the number and types of food items is beyond the scope of this article. On the basis of 9 kcal per g fat, the percentage contribution of fatty acids to total energy intake (en%) was then calculated for ALA, LA, n-3 HUFAs, and n-6 HUFAs. The fatty acid contents of the experimental foods were provided by the manufacturers. All calculations were performed with Microsoft Office Excel (Windows XP; Microsoft). Estimation of Changes in Tissue Composition Resulting From Hypothetical Food Substitution The percentage of n-6 in HUFA was determined using an empirical equation developed by Lands et al,14,15 (see Fig. 3. Lands Equation), which estimates the relative proportions of n-6 and n-3 HUFA in the membrane phospholipids resulting from dietary intake of essential fatty acids. The equation uses the dietary content of the four categories of essential fatty acids (i.e., LA, ALA, n-6 HUFAs, and n-3 HUFAS) expressed as en% to calculate expected %n-6 in HUFA. This empirical formula accounts for metabolic interactions between the four main types of essential fatty acids that determine the composition of n-3 and n-6 in tissues. It should be noted that the %n-6 in HUFA value estimated in the present study reflects the tissue composition that would result if a single individual were to consume all foods offered during the month sampled. Thus, this is not a random sampling of diet selections, so variance in possible tissue outcomes was not modeled. FIGURE 3 View largeDownload slide The Lands Equation accounts for metabolic interactions between the types of fatty acid consumed in the diet expressed as en% as input variables: 18-carbon n-6 PUFA (P6; 18:2n-6 and 18:3n-6), 18-carbon n-3 PUFA (P3; 18:3n-3 and 18:4n-3), 20-and 22-carbon n-6 HUFAs (H6; 20:3 + 20:4 + 22:4 + 22:5), and 20- and 22-carbon n-3 HUFAs (H3; 20:5 + 22:5 + 22:6).The output variable of %n-6 in HUFA expressed the relative amount of n-6 HUFAs in the bioactive pool of n-3 and n-6 HUFAs. Constants are included below the equation. An electronic version is available at www.efaeducation.org. FIGURE 3 View largeDownload slide The Lands Equation accounts for metabolic interactions between the types of fatty acid consumed in the diet expressed as en% as input variables: 18-carbon n-6 PUFA (P6; 18:2n-6 and 18:3n-6), 18-carbon n-3 PUFA (P3; 18:3n-3 and 18:4n-3), 20-and 22-carbon n-6 HUFAs (H6; 20:3 + 20:4 + 22:4 + 22:5), and 20- and 22-carbon n-3 HUFAs (H3; 20:5 + 22:5 + 22:6).The output variable of %n-6 in HUFA expressed the relative amount of n-6 HUFAs in the bioactive pool of n-3 and n-6 HUFAs. Constants are included below the equation. An electronic version is available at www.efaeducation.org. Hypothetical Substitution of High n-3 and Low n-6 FoodsSubstitution of foods with elevated n-3 and diminished n-6 content was performed for a sample (n = 8 representative days) of the mainline menu and for the fast-food menu. In addition, the predicted impact of fish oil supplements providing 1 g per day n-3 HUFA (EPA plus DHA) was also assessed for both the mainline menu and the fast-food menu. Ingredients that were swapped and their respective fatty acid compositions are given in Table II. Swapped food commodities included meat products such as pork, chicken, beef, and turkey, as well as shell eggs and shortening. In addition, LA-rich soy oil comprising all visible and cooking oils was swapped out in favor of a “high oleic” low-LA soy variant. For the fast-food line, the predicted impact of swapping only the frying oil while maintaining the remainder of ingredients the same was evaluated. The procedure described above was used to calculate en% in forecast-corrected servings for each of the four categories of essential fatty acids. The Lands tissue prediction model was then used to estimate %n-6 in HUFA from LA, ALA, n-6 HUFA, and n-3 HUFA intake expressed as en%. TABLE II Fatty Acid Composition of Swapped Food Ingredients Fatty Acid (g/100 g)  Oil  Egg  Chicken  Pork (Loin)  Pork (Back Fat)  Beef  Turkey  Shortening  Canola  Partially Hydrogenated  High Oleic Swapped  USDA  Swapped  USDA  Swapped  USDA  Swapped  USDA  Swapped  USDA  Swapped  USDA  Swapped  USDA  Swapped  Total Saturated  15.25  24.75  12.25  3.1  3  4.31  1.85  1.18  0.79  32.21  16.02  5.87  5.34  1.21  1.85  30.42  16.14  Total Monounsaturated  22.73  61.25  81.63  3.81  4  6.24  2.52  1.36  0.93  41.95  18.39  6.56  4.8  1.52  2.52  50.97  26.75  Total Polyunsaturated  57.33  9.3  6.12  1.36  3  3.23  3.4  0.56  0.38  10.35  15.72  0.43  0.53  1.06  3.4  14.2  8.8  18:2n-6  50.3  8.59  5.1  1.15  1.19  2.88  1.55  0.48  0.2  9.5  7.45  0.34  0.43  0.92  1.55  13.6  10.66  18:3n-3  7.03  0.21  1.02  0.03  1.12  0.01  1.64  0.02  0.09  0.74  6.82  0.05  0.07  0.06  1.64  0.6  1.46  20:4n-6  0  0  0  0.14  0.06  0.08  0.03  0.05  0.02  0.11  0  0.04  0.01  0.06  0.03  0  0  20:5n-3  0  0  0  0  0.03  0.01  0.04  0  0.02  0  0  0  0  0  0.04  0  0  22:5n-3  0  0  0  0  0.05  0.01  0.05  0  0.01  0  0  0  0.02  0.01  0.05  0  0  22:6n-3  0  0  0  0.04  0.18  0.03  0.06  0  0  0  0  0  0  0.01  0.06  0  0  Fatty Acid (g/100 g)  Oil  Egg  Chicken  Pork (Loin)  Pork (Back Fat)  Beef  Turkey  Shortening  Canola  Partially Hydrogenated  High Oleic Swapped  USDA  Swapped  USDA  Swapped  USDA  Swapped  USDA  Swapped  USDA  Swapped  USDA  Swapped  USDA  Swapped  Total Saturated  15.25  24.75  12.25  3.1  3  4.31  1.85  1.18  0.79  32.21  16.02  5.87  5.34  1.21  1.85  30.42  16.14  Total Monounsaturated  22.73  61.25  81.63  3.81  4  6.24  2.52  1.36  0.93  41.95  18.39  6.56  4.8  1.52  2.52  50.97  26.75  Total Polyunsaturated  57.33  9.3  6.12  1.36  3  3.23  3.4  0.56  0.38  10.35  15.72  0.43  0.53  1.06  3.4  14.2  8.8  18:2n-6  50.3  8.59  5.1  1.15  1.19  2.88  1.55  0.48  0.2  9.5  7.45  0.34  0.43  0.92  1.55  13.6  10.66  18:3n-3  7.03  0.21  1.02  0.03  1.12  0.01  1.64  0.02  0.09  0.74  6.82  0.05  0.07  0.06  1.64  0.6  1.46  20:4n-6  0  0  0  0.14  0.06  0.08  0.03  0.05  0.02  0.11  0  0.04  0.01  0.06  0.03  0  0  20:5n-3  0  0  0  0  0.03  0.01  0.04  0  0.02  0  0  0  0  0  0.04  0  0  22:5n-3  0  0  0  0  0.05  0.01  0.05  0  0.01  0  0  0  0.02  0.01  0.05  0  0  22:6n-3  0  0  0  0.04  0.18  0.03  0.06  0  0  0  0  0  0  0.01  0.06  0  0  View Large TABLE II Fatty Acid Composition of Swapped Food Ingredients Fatty Acid (g/100 g)  Oil  Egg  Chicken  Pork (Loin)  Pork (Back Fat)  Beef  Turkey  Shortening  Canola  Partially Hydrogenated  High Oleic Swapped  USDA  Swapped  USDA  Swapped  USDA  Swapped  USDA  Swapped  USDA  Swapped  USDA  Swapped  USDA  Swapped  Total Saturated  15.25  24.75  12.25  3.1  3  4.31  1.85  1.18  0.79  32.21  16.02  5.87  5.34  1.21  1.85  30.42  16.14  Total Monounsaturated  22.73  61.25  81.63  3.81  4  6.24  2.52  1.36  0.93  41.95  18.39  6.56  4.8  1.52  2.52  50.97  26.75  Total Polyunsaturated  57.33  9.3  6.12  1.36  3  3.23  3.4  0.56  0.38  10.35  15.72  0.43  0.53  1.06  3.4  14.2  8.8  18:2n-6  50.3  8.59  5.1  1.15  1.19  2.88  1.55  0.48  0.2  9.5  7.45  0.34  0.43  0.92  1.55  13.6  10.66  18:3n-3  7.03  0.21  1.02  0.03  1.12  0.01  1.64  0.02  0.09  0.74  6.82  0.05  0.07  0.06  1.64  0.6  1.46  20:4n-6  0  0  0  0.14  0.06  0.08  0.03  0.05  0.02  0.11  0  0.04  0.01  0.06  0.03  0  0  20:5n-3  0  0  0  0  0.03  0.01  0.04  0  0.02  0  0  0  0  0  0.04  0  0  22:5n-3  0  0  0  0  0.05  0.01  0.05  0  0.01  0  0  0  0.02  0.01  0.05  0  0  22:6n-3  0  0  0  0.04  0.18  0.03  0.06  0  0  0  0  0  0  0.01  0.06  0  0  Fatty Acid (g/100 g)  Oil  Egg  Chicken  Pork (Loin)  Pork (Back Fat)  Beef  Turkey  Shortening  Canola  Partially Hydrogenated  High Oleic Swapped  USDA  Swapped  USDA  Swapped  USDA  Swapped  USDA  Swapped  USDA  Swapped  USDA  Swapped  USDA  Swapped  Total Saturated  15.25  24.75  12.25  3.1  3  4.31  1.85  1.18  0.79  32.21  16.02  5.87  5.34  1.21  1.85  30.42  16.14  Total Monounsaturated  22.73  61.25  81.63  3.81  4  6.24  2.52  1.36  0.93  41.95  18.39  6.56  4.8  1.52  2.52  50.97  26.75  Total Polyunsaturated  57.33  9.3  6.12  1.36  3  3.23  3.4  0.56  0.38  10.35  15.72  0.43  0.53  1.06  3.4  14.2  8.8  18:2n-6  50.3  8.59  5.1  1.15  1.19  2.88  1.55  0.48  0.2  9.5  7.45  0.34  0.43  0.92  1.55  13.6  10.66  18:3n-3  7.03  0.21  1.02  0.03  1.12  0.01  1.64  0.02  0.09  0.74  6.82  0.05  0.07  0.06  1.64  0.6  1.46  20:4n-6  0  0  0  0.14  0.06  0.08  0.03  0.05  0.02  0.11  0  0.04  0.01  0.06  0.03  0  0  20:5n-3  0  0  0  0  0.03  0.01  0.04  0  0.02  0  0  0  0  0  0.04  0  0  22:5n-3  0  0  0  0  0.05  0.01  0.05  0  0.01  0  0  0  0.02  0.01  0.05  0  0  22:6n-3  0  0  0  0.04  0.18  0.03  0.06  0  0  0  0  0  0  0.01  0.06  0  0  View Large RESULTS Theoretical Menu-Item Substitution On the basis of the reported meal consumption patterns of active duty Personnel from the HRBS, we characterized the fatty acid composition (LA, ALA, n-6 HUFA, and n-3 HUFA) of a representative 28-day Garrison mainline menu. The mainline menu consisted of a total Garrison sum offering of 15,774,387 cal over 28 days, or equivalently, a daily forecasted average of (5.63 × 105) ± (3.60 × 104) kcal per day (Fig. 4). The daily average amount of LA, ALA, n-6 HUFA, and n-3 HUFA consumed in the Garrison mainline diet is also shown in Figure 4. Thus, in the current Garrison food offerings, the availability of both short-chain and long-chain n-6 fatty acids significantly outweighs that of n-3 fatty acids. These 4 categories of dietary fatty acids were entered into the Lands Equation as percentage of total energy (en%) to obtain a predicted tissue composition of 78% n-6 in HUFA on the basis of a single person consuming all garrison foods offered in a month. FIGURE 4 View largeDownload slide Summary of current mainline menu offerings. (A) Average total calorie forecasted = (5.63 × 105) ± (3.60 × 104) kcal. (B,C) Summary of total fatty acid amounts offered in current menu mainline foods on a daily average basis. (B) Short chain PUFA in kilograms. (C) Long-chain PUFA in grams. FIGURE 4 View largeDownload slide Summary of current mainline menu offerings. (A) Average total calorie forecasted = (5.63 × 105) ± (3.60 × 104) kcal. (B,C) Summary of total fatty acid amounts offered in current menu mainline foods on a daily average basis. (B) Short chain PUFA in kilograms. (C) Long-chain PUFA in grams. Substitutions (Table II) were performed for a representative sample of 8 days for the mainline menu. Swapping in n-3-rich foods and substituting LA-rich soy oil with a “high oleic” low-LA soy variant resulted in an increase in dietary ALA and n-3 HUFAs accompanied by a decrease in dietary LA and n-6 HUFAs. The change in the fatty acid composition (en%) of the diet achieved by these substitutions is shown in Table III. These changes in the fatty acid composition of the diet translated to a 19% decrease in the predicted percentage n-6 in tissue HUFA value, from 76.4% to 57.1%. TABLE III Predicted % n-6 in HUFA Calculated From en% 18:3n-3, en% 18:2n-6, en% n-3 HUFA, and en% n-6 HUFA for Mainline and Fast-food Menus in Both Current and Swapped Conditions Average Daily Dietary Intakes (ML, n = 8 Representative Days; FF, n = 1 Day)  ML  FF Oil Only  FF Oil + Foods  Current  Supplemented  Swapped  Current  Swapped  Current  Swapped     en% 18:3n-3  0.58  0.54  1.23  0.50  0.47  0.50  1.08     en% 18:2 n-6  4.30  3.93  2.90  5.37  5.01  5.37  3.89     en% n-3 HUFA  0.05  0.38  0.13  0.02  0.02  0.02  0.08     en% n-6 HUFA  0.09  0.09  0.08  0.06  0.06  0.06  0.04  Plasma PL: Predicted HUFA Proportions  20:5n-3 + 22:5n-3 (as % of HUFA in PL)     10.1  16.4  25.1  6.9  7.0  6.9  18.4  Other HUFA (as % of HUFA in PL)  22:6n-3; 20:3n9  13.4  29.7  17.7  14.6  14.9  14.6  18.6  % n-6 in HUFA (20:3n-6+20:4n-6 as % of HUFA in PL)     76.4  53.8  57.1  78.5  78.1  78.5  63.0  %n-3 in HUFA     23.6  46.1  42.9  21.5  21.9  21.5  37.0  Omega-3 Index     3.0  7.0  6.5  2.6  2.7  2.6  5.4  Average Daily Dietary Intakes (ML, n = 8 Representative Days; FF, n = 1 Day)  ML  FF Oil Only  FF Oil + Foods  Current  Supplemented  Swapped  Current  Swapped  Current  Swapped     en% 18:3n-3  0.58  0.54  1.23  0.50  0.47  0.50  1.08     en% 18:2 n-6  4.30  3.93  2.90  5.37  5.01  5.37  3.89     en% n-3 HUFA  0.05  0.38  0.13  0.02  0.02  0.02  0.08     en% n-6 HUFA  0.09  0.09  0.08  0.06  0.06  0.06  0.04  Plasma PL: Predicted HUFA Proportions  20:5n-3 + 22:5n-3 (as % of HUFA in PL)     10.1  16.4  25.1  6.9  7.0  6.9  18.4  Other HUFA (as % of HUFA in PL)  22:6n-3; 20:3n9  13.4  29.7  17.7  14.6  14.9  14.6  18.6  % n-6 in HUFA (20:3n-6+20:4n-6 as % of HUFA in PL)     76.4  53.8  57.1  78.5  78.1  78.5  63.0  %n-3 in HUFA     23.6  46.1  42.9  21.5  21.9  21.5  37.0  Omega-3 Index     3.0  7.0  6.5  2.6  2.7  2.6  5.4  FF, fast food; ML, mainline; PL, plasma. View Large TABLE III Predicted % n-6 in HUFA Calculated From en% 18:3n-3, en% 18:2n-6, en% n-3 HUFA, and en% n-6 HUFA for Mainline and Fast-food Menus in Both Current and Swapped Conditions Average Daily Dietary Intakes (ML, n = 8 Representative Days; FF, n = 1 Day)  ML  FF Oil Only  FF Oil + Foods  Current  Supplemented  Swapped  Current  Swapped  Current  Swapped     en% 18:3n-3  0.58  0.54  1.23  0.50  0.47  0.50  1.08     en% 18:2 n-6  4.30  3.93  2.90  5.37  5.01  5.37  3.89     en% n-3 HUFA  0.05  0.38  0.13  0.02  0.02  0.02  0.08     en% n-6 HUFA  0.09  0.09  0.08  0.06  0.06  0.06  0.04  Plasma PL: Predicted HUFA Proportions  20:5n-3 + 22:5n-3 (as % of HUFA in PL)     10.1  16.4  25.1  6.9  7.0  6.9  18.4  Other HUFA (as % of HUFA in PL)  22:6n-3; 20:3n9  13.4  29.7  17.7  14.6  14.9  14.6  18.6  % n-6 in HUFA (20:3n-6+20:4n-6 as % of HUFA in PL)     76.4  53.8  57.1  78.5  78.1  78.5  63.0  %n-3 in HUFA     23.6  46.1  42.9  21.5  21.9  21.5  37.0  Omega-3 Index     3.0  7.0  6.5  2.6  2.7  2.6  5.4  Average Daily Dietary Intakes (ML, n = 8 Representative Days; FF, n = 1 Day)  ML  FF Oil Only  FF Oil + Foods  Current  Supplemented  Swapped  Current  Swapped  Current  Swapped     en% 18:3n-3  0.58  0.54  1.23  0.50  0.47  0.50  1.08     en% 18:2 n-6  4.30  3.93  2.90  5.37  5.01  5.37  3.89     en% n-3 HUFA  0.05  0.38  0.13  0.02  0.02  0.02  0.08     en% n-6 HUFA  0.09  0.09  0.08  0.06  0.06  0.06  0.04  Plasma PL: Predicted HUFA Proportions  20:5n-3 + 22:5n-3 (as % of HUFA in PL)     10.1  16.4  25.1  6.9  7.0  6.9  18.4  Other HUFA (as % of HUFA in PL)  22:6n-3; 20:3n9  13.4  29.7  17.7  14.6  14.9  14.6  18.6  % n-6 in HUFA (20:3n-6+20:4n-6 as % of HUFA in PL)     76.4  53.8  57.1  78.5  78.1  78.5  63.0  %n-3 in HUFA     23.6  46.1  42.9  21.5  21.9  21.5  37.0  Omega-3 Index     3.0  7.0  6.5  2.6  2.7  2.6  5.4  FF, fast food; ML, mainline; PL, plasma. View Large A theoretical modeling addition of 1 g per day n-3 HUFA (EPA plus DHA) as a salmon oil supplement resulted in a predicted tissue composition of 53.8% n-6 in HUFA, a 22.6% decrease relative to current offerings (Table III). However, background intakes of omega-6 fatty acids may be very high at baseline necessitating more than 1 g per day to substantially alter tissue levels. As well, this modeling did not account for foods from other sources. Theoretical Fast-Food Line Menu Swapping The fatty acid composition (en%) of the fast-food-line menu is given in Table III. The current fast-food line offerings contribute to a predicted 78.5% n-6 in HUFA. For this menu, we modeled the change in fatty acid composition and resulting predicted tissue composition achieved by the following: (1) substitution of only frying oils (i.e., high oleic oil in place of canola and partially hydrogenated oil) and (2) substitution of all oils and the food commodities listed in Table III. A comparison of the fatty acid composition (en%) of current and swapped menus for the fast-food-line is given in Table III. We report no significant change in the predicted %n-6 in HUFA from current fast-food-line offerings compared to offerings with only frying oil swapped. However, a 15.5% decrease in n-6 in HUFA was observed when both oils and additional food commodities were swapped (Table III). DISCUSSION On the basis of our modeling, current Garrison food offerings are likely to result in low, and therefore unhealthy, tissue membrane proportions of n-3 HUFAs relative to n-6 HUFAs. The fatty acid composition of the current Garrison diet results in a predicted %n-6 in HUFA value of 78%, a figure similar to the 83% predicted n-6 in HUFA from consuming the typical American diet.15 It should be noted that the percentage of n-6 in HUFA has been found to be a biomarker for omega-6 status in tissues16,17 and has furthermore been strongly associated with coronary heart disease mortality.16,17 By comparison to the fatty acid status of worldwide populations, the modeled estimated %n-6 in tissue HUFA from consuming the entire garrison diet is strikingly high. In a survey of serum fatty acid profiles of four different populations (i.e., rural Japanese, urban Japanese, Japanese Americans, and Caucasian Americans), Iso et al18 found that %n-6 in tissue HUFA varied over a range of 44.9%, from 36.3% n-6 in HUFA in a rural Japanese population to 81.2% n-6 in HUFA in a Caucasian American population. Similarly, the mean %n-6 in HUFA was found to be 65.6% for a sample of women in a Mediterranean population,19 which is significantly lower than the value resulting from consuming a typical garrison diet. We caution that these estimates reflect the composition of all foods in the garrison diet, and not indicative of what any one individual will consume when eating selected items. The current Garrison diet can be said to be deficient in n-3 fatty acids, based on our modeling. Use of omega-3 supplements is one, but not the only alternative to elevate this situation. Hibbeln et al20 estimated that 3.5 g per day of n-3 HUFA would be necessary in typical American diet to achieve a tissue composition approximating 60% n-3 HUFA.20 This 2006 study by Hibbeln et al20 defined deficiency as attributable risk from 13 major n-3-related morbidity and mortality outcomes, such as cardiovascular disease and bipolar disorder. Hibbeln et al20 estimated that 1 g per day would substantially reduce risk of these illnesses. The representative U.S. Garrison diet, like the typical diet of the general U.S. population, does not currently succeed in meeting the requirement of this definition. Substitution of n-3 rich eggs, poultry, pork, and other food commodities, combined with use of low-LA oils, may contribute significantly to attaining healthier n-6/n-3 proportions in the tissue. It should be noted that when only dietary LA was lowered by substituting frying oil in the fast-food-line, the observed change in %n-6 in HUFA was negligible. Yet, %n-6 in HUFA was decreased significantly when other food commodities were substituted with n-3 and low omega-6-rich variants, in addition to swapping out high-LA oil. This suggests that lowering dietary n-6 in combination with elevating n-3 acts more potently than either method alone to lower tissue composition of n-6. Supplementation of the mainline food offerings with the use of capsules achieves a similar effect but may entail problems with compliance as previously noted. This current modeling study has several limitations. The HRBS dietary survey information was limited to only two questions and the response options were categorical in nature rather than based on portion sizes of specific food items. In addition, we used an empirical model and the accuracy of this model prediction has not been demonstrated in a clinical trial to date. However, now that this model is in place, clinical trials can be conducted to determine the efficacy of dietary changes in effecting more favorable tissue compositions of fatty acids. In addition, only a small representative sample of 28 days out of a 365-day cycle offering was experimentally manipulated in this model and it is known that serving sizes are not strictly enforced in some serving environments and thus may result in additional variation in the fatty acid composition of foods served and resulting tissue compositions from consuming these diets. Lastly, this modeling does not reflect actual consumption of the garrison diet or its individual components. Uncertainties resulting from these aspects of the study should be taken into account when evaluating the robustness of these model predictions. A linear regression analysis comparing %n-6 in HUFA predicted by the Lands Equation, and %n-6 in HUFA determined by blood fraction analysis resulted in a correlation coefficient of 0.73 (P = 0.000000) (n = 92).21 This analysis was based on a literature search of 34 clinical trials that reported (1) dietary intake of at least LA (18:2n-6) and ALA (18:3n-3) and (2) the amounts of at least AA (20:4n-6), EPA (20:5n-3), and DHA (22:6n-3) in phospholipids or total lipids of plasma, serum, or red blood cell. Therefore, we can expect the predicted changes in tissue composition modeled here to be a reasonable estimation of actual proportions of n-6 and n-3 HUFAs resulting from consuming the garrison diet. The tissue compositions of n-3 HUFAs predicted by this modeling are consistent with measures reported in a recent study of active duty U.S. military personnel. In a case–control study, Lewis et al8 reported that %n-6 HUFAs averaged 78% (range 59–89) in a sample population of 800 apparently healthy active duty personnel. Lewis et al8 assessed whether deficiencies of n-3 HUFAs, particularly DHA, were associated with increased risk of suicide among a large random sample of active duty U.S. military. In a sample population (n = 800) of health controls in active duty U.S. military, %n-6 in HUFA was determined to be 78%. The similarity of this figure to the 76.4% n-6 in HUFA predicted from consuming the current mainline diet in this model suggests that the fatty acid composition, and therefore also resulting tissue compositions, of this sample menu are representative of actual food intake. Food substitutions like those described herein raise questions regarding commodity availability and economic feasibility. To begin to answer the question of whether the substitutions modeled here are economically acceptable at the garrison level, we determined the economic impact of changing the source of chicken shell eggs for egg-based dishes in the mainline menu. At today's market prices, regular eggs versus high omega-3 eggs for 500 garrison Personnel eating 1 egg per day cost an estimated $1,120.00 per month regular versus $1,423.33 per mo. However, his price differential may be reduced by purchasing in bulk and should be weighed against the possible potential health benefit of incorporating high omega-3 eggs into the garrison diet. CONCLUSION The diet offered in the U.S. Garrison menu can be characterized as having inadequate n-3 fatty acid and an oversupply of n-6 fatty acids, resulting in a high predicted tissue composition of n-6 HUFA. The tissue composition of n-6 in HUFA can be lowered significantly by substitution of n-3 rich eggs, poultry, pork, and other food commodities into existing recipes, combined with use on low LA visible oils and cooking oils. Dietary supplements such as fish oil pills can improve n-3:n-6 status, but success is dependent on voluntary compliance. The modeling effort reported in this article suggests that substitution of food items such as eggs, chicken meat, pork, and salad dressings with like products, but with lowered n-6 and elevated n-3 levels will produce marked improvements in n-3:n-6 HUFA status, and may be a viable way to decrease pathogenesis of diseases consequent to imbalances in tissue n-3:n-6 HUFA. ACKNOWLEDGMENTS The authors gratefully acknowledge the assistance of Viviane Enslein and Samantha Wise for their work in formatting and editing various versions of this article. The Intramural program of the National Institute on Alcohol Abuse and Alcoholism provided support for this work. REFERENCES 1. Freeman MP, Hibbeln JR, Wisner KL, et al.   Omega-3 fatty acids: evidence basis for treatment and future research in psychiatry. J Clin Psychiatry  2006; 67( 12): 1954– 67. Google Scholar CrossRef Search ADS PubMed  2. U.S. Department of Health and Human Services, USDA Dietary Guidelines for Americans, 2005 . Washington, DC, U.S. Government Printing Office, 2005. Available at http://www.health.gov/dietaryguidelines/dga2005/document/pdf/DGA2005.pdf; accessed March 31, 2014. 3. Trumbo P, Schlicker S, Yates AA, Poos M Dietary reference intakes for energy, carbohydrate, fiber, fat, fatty acids, cholesterol, protein and amino acids. J Am Diet Assoc  2002; 102: 1621– 30. Google Scholar CrossRef Search ADS PubMed  4. Hibbeln JR Depression, suicide and deficiencies of omega-3 essential fatty acids in modern diets. World Rev Nutr Diet  2009; 99: 17– 30. Google Scholar CrossRef Search ADS PubMed  5. Appleton KM, Gunnell D, Peters TJ, Ness AR, Kessler D, Rogers PJ No clear evidence of an association between plasma concentrations of n-3 long-chain polyunsaturated fatty acids and depressed mood in a non-clinical population. Prostaglandins Leukot Essent Fatty Acids  2008; 78( 6): 337– 42. Google Scholar CrossRef Search ADS PubMed  6. Lin PY, Su KP A meta-analytic review of double-blind, placebo-controlled trials of antidepressant efficacy of omega-3 fatty acids. J Clin Psychiatry  2007; 68( 7): 1056– 61. Google Scholar CrossRef Search ADS PubMed  7. Williams T Suicides Outpacing War Deaths for Troops. New York Times , June 8, 2012, Available at http://www.nytimes.com/2012/06/09/us/suicides-eclipse-war-deaths-for-us-troops.html?_r=0; accessed April 2, 2014. 8. Lewis MD, Hibbeln JR, Johnson JR, Lin YH, Hyun DY, Loewke JD Suicide deaths of active duty US military and omega-3 fatty acid status: a case control comparison. J Clin Psychiatry  2011; 72( 12): 1585– 90. Google Scholar CrossRef Search ADS PubMed  9. Centers for Disease Control and Prevention About the National Health and Nutrition Examination Survey . Available at http://www.cdc.gov/nchs/nhanes/about_nhanes.htm; accessed April 4, 2014. 10. Bray RM, Hourani LL, Rae Olmsted KL, et al.   2005 Department of Defense Survey of Health Related Behaviors Among Active Duty Military Personnel: A Component of the Defense Lifestyle Assessment Program (DLAP), Final report (prepared for the Assistant Secretary of Defense [Health Affairs] , U.S. Department of Defense, Cooperative Agreement No. DAMD17-00-2-0057, by RTI International. Available at http://tricare.mil/tma/dhcape/surveys/coresurveys/surveyhealthrelatedbehaviors/downloads/Final%202011%20HRB%20Active%20Duty%20Survey%20Exec%20Summary.pdf; accessed March 31, 2014. 11. U.S. Department of Health and Human Services, Healthy People 2010 Understanding and Improving Health , Ed 2. Washington, DC, U.S. Government Printing Office, 2000. Available at http://www.healthequityks.org/download/Hllthy_People_2010_Improving_Health.pdf; accessed March 31, 2014. 12. KIM-2 (Keep It Managed) software for food choices . Available at http://www.efaeducation.org/tools.html; assessed June 16, 2014. 13. U.S. Department of Agriculture, Agricultural Research Service, Nutrient Data Laboratory Composition of Foods Raw, Processed, Prepared USDA National Nutrient Database for Standard Reference, Release 19 . Washington, DC, USDA, 2006. Available at http://www.ars.usda.gov/SP2UserFiles/Place/12354500/Data/SR19/SR19_doc.pdf; accessed March 31, 2014. 14. Lands B Measuring blood fatty acids as a surrogate indicator for coronary heart disease risk in population studies. World Rev Nutr Diet  2009; 100: 22– 34. Google Scholar CrossRef Search ADS PubMed  15. Lands WE, Libelt B, Morris A, et al.   Maintenance of lower proportions of (n - 6) eicosanoid precursors in phospholipids of human plasma in response to added dietary (n - 3) fatty acids. Biochim Biophys Acta  1992; 1180( 2): 147– 62. Google Scholar CrossRef Search ADS PubMed  16. Ramsden CE Nutrition by the Numbers . Atlanta, GA, Applied Nutritional Biochemistry, 2007. 17. Stark KD The percentage of n-3 highly unsaturated fatty acids in total HUFA as a biomarker for omega-3 fatty acid status in tissues. Lipids  2008; 43( 1): 45– 53. Google Scholar CrossRef Search ADS PubMed  18. Iso H, Sato S, Folsom AR, et al.   Serum fatty acids and fish intake in rural Japanese, urban Japanese, Japanese American and Caucasian American men. Int J Epidemiol  1989; 18( 2): 374– 81. Google Scholar CrossRef Search ADS PubMed  19. Garcia-Prieto MD, Tebar FJ, Nicolas F, Larque E, Zamora S, Garaulet M Cortisol secretary pattern and glucocorticoid feedback sensitivity in women from a Mediterranean area: relationship with anthropometric characteristics, dietary intake and plasma fatty acid profile. Clin Endocrinol (Oxf)  2007; 66( 2): 185– 91. Google Scholar CrossRef Search ADS PubMed  20. Hibbeln JR, Nieminen LR, Blasbalg TL, Riggs J, Lands WEM Healthy intakes of n-3 and n-6 fatty acids: estimations considering worldwide diversity. Am J Clin Nutr  2006; 83: 1483S– 93S. Google Scholar PubMed  21. Lands WE Functional foods in primary prevention or nutraceuticals in secondary prevention? Curr Topics Nutraceut Res  2003; 1: 1– 7. Reprint & Copyright © Association of Military Surgeons of the U.S.
TI - Understanding Diet and Modeling Changes in the Omega-3 and Omega-6 Fatty Acid Composition of U.S. Garrison Foods for Active Duty Personnel
JF - Military Medicine
DO - 10.7205/MILMED-D-14-00199
DA - 2014-11-01
UR - https://www.deepdyve.com/lp/oxford-university-press/understanding-diet-and-modeling-changes-in-the-omega-3-and-omega-6-RCOi6cLnsr
SP - 168
EP - 175
VL - 179
IS - suppl_11
DP - DeepDyve
ER -