Definitions of health related terms and defining the problem

Health - the state of being free from illness or injury.

Disease - a disorder of structure or function in a human, animal, or plant, especially one that produces specific signs or symptoms or that affects a specific location and is not simply a direct result of physical injury.

Food - any nutritious substance that people or animals eat or drink, or that plants absorb, in order to maintain life and growth.

Healthcare - the maintenance and improvement of physical and mental health, especially through the provision of medical services.