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.
Vegetarianism
Research funded by the U.S. National Institutes of Health has shown that the average Adventist in California lives 4 to 10 years longer than the average Californian. The research, as cited by the cover story of the November 2005 issue of "National Geographic", asserts that Adventists live longer because they do not smoke or drink alcohol, have a day of rest every week, and maintain a healthy, low-fat vegetarian diet that is rich in nuts and beans. The cohesiveness of Adventists' social networks has also been put forward as an explanation for their extended lifespan.
Since Dan Buettner's 2005 "National Geographic" story about Adventist longevity, his book, "The Blue Zones: Lessons for Living Longer From the People Who've Lived the Longest", named Loma Linda, California a "blue zone" because of the large concentration of Seventh-day Adventists. He cites the Adventist emphasis on health, diet, and Sabbath-keeping as primary factors for Adventist longevity.