There's an old military saying that "an army marches on its belly."
As America celebrates 250 years of independence, it's worth a look at how Continental soldiers, sailors and Marines got the calories and nutrients needed to fight in the Revolutionary War, often under harsh conditions.
The military had two types of rations, one for at home and one for the field. The rations issued in a garrison generally included freshly baked bread, fresh meat and fruits and vegetables.
Field rations or at sea included hard biscuits, salted beef or pork, salted fish, molasses, rice and dried peas or beans.
These were often hard to eat and distasteful. The meat and fish were salted so that they could be better preserved, and flour was often made into hard biscuits that didn't mold as fast but were hard on teeth.
Commissaries either issued spruce beer to the troops or provided an allowance to buy it, since water wasn't always safe to drink.
The quantity of rations was standardized in theory but in practice depended on availability.
Troops often foraged for food to supplement the meager amount of food they were given, finding nuts, berries and edible plants. They generally cooked their food in tin or iron kettles/skillets over a campfire.
Compared with current dietary requirements, their rations, if they met the standard issue, provided more calories, twice as much protein and an adequate supply of all minerals and vitamins with the exception of vitamins A and C, according to the Army Quartermaster Museum's "The History of Rations."