text: Nutritional Readiness
  8-15. Soldiers need to limit sodium consumption. Healthy eating patterns limit sodium to less than 2,300
  milligrams per day for adults. Sodium is an essential nutrient and is needed by the body in relatively small
  quantities, provided that substantial sweating does not occur.
  8-16. Soldiers need to limit alcohol consumption. In the strictest sense, alcohol is not a performance nutrient.
  If Soldiers consume alcohol, it should be in moderation—up to one drink per day for women and up to two
  drinks per day for men—and only by adults of legal drinking age. One alcoholic drink-equivalent consists
  of—
  * 12 fluid ounces of regular beer (5 percent alcohol).
  * 5 fluid ounces of wine (12 percent alcohol).
  * 1.5 fluid ounces of 80 proof distilled spirits (40 percent alcohol).
  The amount of alcohol and calories in beverages varies. Soldiers account for alcohol within the limits of
  healthy eating patterns so that they do not exceed calorie limits.
  BODY COMPOSITION
  8-17. The body is comprised of water, protein, minerals, and fat. A two-compartment model of body
  composition divides the body into a fat component and fat-free component. The total amount of body fat
  consists of essential fat and storage fat. Fat in the marrow of bones, heart, lungs, liver, spleen, kidneys,
  intestines, muscles, and certain tissues throughout the central nervous system is called essential fat. Non-
  essential body fat is called storage fat. Normal bodily function requires essential fat. Women have higher
  essential fat than men because it includes sex-characteristic fat related to child bearing. Storage fat is located
  around internal organs (internal storage fat) and directly beneath the skin (subcutaneous storage fat). It
  provides bodily protection and serves as an insulator to conserve body heat. The relationship between
  subcutaneous fat and internal fat may not be the same for all individuals and may fluctuate during the life
  cycle.
  8-18. Lean body mass represents the weight of your muscles, bones, ligaments, tendons, and internal organs.
  Lean body mass differs from fat-free mass (known as FFM). Since there is some essential fat in the marrow
  of your bones and internal organs, the lean body mass includes a small percentage of essential fat. However,
  with the two-component model of body composition, these sources of essential fat are estimated and
  subtracted from total body weight to obtain the fat-free mass. Practical methods of assessing body
  composition such as skinfold thickness (or caliper) testing, bioelectrical impedance analysis, air displacement
  plethysmograph, and hydrostatic weighing are based on the two-compartment (lean body mass and fat-free
  mass) model of body composition. The three-compartment model of body composition includes a third
  component where the fat-free mass is further divided into lean tissue mass and bone mineral content. The
  dual-energy X-ray absorptiometry (known as DEXA) scan is an example of a three-compartment model of
  body composition assessment. Soldiers should consult with a registered dietitian or the Army Wellness
  Center for assistance with body composition assessments and interpretation of results.
  8-19. Optimal lean body mass to fat-free mass ratios for Soldiers differ depending upon their primary and
  secondary mission roles. Dietitians consider chronic disease risk, individual illness and injury patterns, body
  composition history, ethnicity, and specific mission requirements when determining their most effective task-
  specific body composition. Soldiers should be reminded that physical performance cannot be accurately
  predicted solely based on body weight and composition. A single and rigid optimal body composition should
  not be recommended for any physical training event or unit of Soldiers.
  8-20. Following a healthy eating pattern (consuming the number of servings of carbohydrate, protein and
  healthy fats from the food groups to meet individual calorie needs) supports a healthy body composition. The
  frequency, intensity, and type of physical activity also impact body composition. To perform optimally at
  any physical task requires proper nutrition combined with physical training. All Soldiers are encouraged to
  achieve and maintain body composition. See AR 600-9 for standards for body fat.