HDRs are a spin-off of MREs. They were developed as a means of feeding large populations of displaced persons or refugees under emergency conditions. A single HDR is designed to provide a full day’s sustenance to a moderately malnourished individual (as opposed to MREs, where you need three per day to feed a soldier in the field). HDRs also differ from MREs in that they contain no animal products or by-products so as to be acceptable to a wide range of consumers with religious and dietary restrictions. Each HDR contains 2200 calories.
 
Since the meal is designed as a complete day’s supply of food, a minimum of two entrees is provided in each meal bag. Complementary components are also included to provide the balance of the daily nutritional requirements that call for not less than 2200 calories, broken down as 10-13% protein, 27-30% fat, and not less than 60% carbohydrates. A spoon and a non-alcohol based moist towelette are the only non-food components in the meal bag.