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.
LifeStraw
The LifeStraw water filters are designed by the Swiss-based Vestergaard Frandsen. While originally developed for people living in developing nations and for distribution in humanitarian crisis, the LifeStraw has gained popularity as a consumer product. The LifeStraw is now used as a tool for survivalists and packed in emergency preparedness kits in addition to being used to help combat clean water scarcity worldwide. LifeStraw personal filters can provide clean water for up to a year, and the LifeStraw Family filters a maximum of 18,000 litres of water, providing safe drinking water for a family of five for up to three years.