Human
In general, humans can survive for two to eight weeks without food, depending on stored body fat. Survival without water is usually limited to three or four days. About 36 million humans die every year from causes directly or indirectly related to starvation. Childhood malnutrition is also common and contributes to the global burden of disease. However global food distribution is not even, and obesity among some human populations has increased rapidly, leading to health complications and increased mortality in some developed, and a few developing countries. Worldwide over one billion people are obese, while in the United States 35% of people are obese, leading to this being described as an "obesity epidemic." Obesity is caused by consuming more calories than are expended, so excessive weight gain is usually caused by an energy-dense diet.
Drink
When the human body becomes dehydrated, it experiences thirst. This craving of fluids results in an instinctive need to drink. Thirst is regulated by the hypothalamus in response to subtle changes in the body's electrolyte levels, and also as a result of changes in the volume of blood circulating. The complete elimination of drinks, that is, water, from the body will result in death faster than the removal of any other substance. Water and milk have been basic drinks throughout history. As water is essential for life, it has also been the carrier of many diseases.