Human nutrition is the provision to obtain
the materials necessary to support life. In general,
people can survive for two to eight weeks without
food, depending on stored body fat and muscle mass.
Survival without water is usually limited to three
or four days. Obesity is caused by consuming more
calories than are expended, with many attributing
excessive weight gain to a combination of overeating
of "unhealthy" (high fat, high sugar, high
carbohydrate) foods and insufficient exercise.
[Adapted from Wikipedia]
