According to the U.S. Army Research Institute of Environmental Medicine (USARIEM), military personnel who work in hot climates are at a greater risk for dehydration, which can affect physical performance and even be life-threatening. The USARIEM says military personnel need 4 to 12 quarts of water when working in a warm environment. Soldiers should not skip meals because food can provide up to 10 percent of a person's daily fluid requirement and over 50 percent of beverages are consumed with meals.
The USARIEM says an ideal diet in a hot environment is high in complex carbohydrates and includes a moderate amount of protein and fat. Carbohydrates are important because they provide fast fuel for physical and mental performance. Examples of healthy, complex carbohydrates that are lower in protein and fat include bread, crackers, fruit and fruit juice.
The USARIEM says soldiers may need 10 to 40 percent more calories in cold climates, depending on activity level. Adequate calories help produce heat to prevent hypothermia and fuel muscles. Snacks between meals can help meet a soldier's increased calorie needs. Hot meals are also important in cold weather conditions to warm the body and encourage adequate calorie intake. Military personnel working in cold climates need 2 to 6 quarts of water a day and should drink even if they are not thirsty.