A diet for Army personnel adheres to military dietary references intakes (MDRIs). MDRIs are similar to recommended dietary allowances (RDAs), the values used to define a healthful diet for the general population, but are adjusted for calories based on the increased activity levels of people in the Army. A healthful diet for Army personnel focuses on fruits, vegetables, whole grains, low-fat dairy products, lean proteins and heart-healthy fats.
The MDRIs for calories can meet the needs of the average Army personnel. Men and women should have 3,250 to 4,600 and 2,300 to 3,150 calories, respectively, per day, which will fluctuate based on size. The Departments of the Navy, Air Force and Army say the daily calorie requirements are based on a 174-pound, 69-inch man and a 136-pound, 64-inch woman. Individuals who are smaller than the reference size will require fewer calories, and larger individuals might have higher needs.
Activity level and environment also affect caloric needs. Federal guidelines say heavy work or prolonged, vigorous physical training can increase calorie needs by 125 percent. Cold temperatures can increase calorie requirements by 5 percent to 10 percent, and individuals who perform strenuous work at altitudes above 10,000 feet might need 6,000 to 7,000 calories or 50 to 60 calories per kilogram of body weight per day.
Carbohydrates, protein and fat are considered macronutrients. The MDRIs recommend a diet that is 50 percent to 55 percent carbohydrates, 10 percent to 15 percent protein and less than 30 percent fat. Saturated fat should comprise less than 10 percent of the diet, and cholesterol should be limited to less than 300 mg per day.
The U.S. Army recommends a diet rich in fruits, vegetables, whole grains, low-fat or non-fat dairy products and lean proteins such as fish, beans, egg whites, chicken breast and lean ground beef. Fried items, high-fat meats, whole-milk products, refined grains like white bread and added sugar should be avoided because they have few nutritional benefits and can contribute to chronic diseases. Healthy fats are unsaturated fats like olive or vegetable oils and fat from fish, avocados and nuts. Saturated and trans-fats are unhealthy and often found in fast food, creamy salad dressings, mayonnaise, butter, lard, desserts, pastries and cream sauces.
The Army recommends that its personnel drink 50 percent to 75 percent of their body weight in ounces. For example, an active, 150-pound soldier should drink about 112 oz. of fluid per day (150 x 0.75 = 112.5). Individuals who live in dry climates or do strenuous activities should add an additional 16 oz. of fluid per day. Water is the best hydration fluid, but soldiers who are continuously active for more than 1.5 hours might benefit from sports beverages.
Meals Ready to Eat (MREs) are rations designed for Army personnel in combat situations. Three MREs a day can meet the daily requirements for calories and nutrients. The Army says the average MRE contains 1,250 calories and is 13 percent protein, 36 percent fat and 51 percent carbohydrate. Each MRE also contains one-third of the daily requirements for vitamins and minerals. The fat content of an MRE can be higher than the MDRI for fat to increase the calories while minimizing the ration's size.
Army personnel must monitor their weight to determine if they are getting enough calories and nutrition. Over-consumption of calories can lead to weight gain, obesity and obesity-related diseases like heart disease, cancer, diabetes and stroke. The Army notes that MDRIs might not meet the nutritional needs of pregnant or breastfeeding military women and those with illnesses, injuries, infections, chronic diseases or trauma.