In 1991, approximately 200 studies that examined the relationship between fruit and vegetable intake and cancers of the lung, colon, breast, cervix, esophagus, oral cavity, stomach, bladder, pancreas, and ovary are reviewed.
A statistically significant protective effect of fruit and vegetable consumption was found in 128 of 156 dietary studies. For most cancer sites, persons with low fruit and vegetable intake (at least the lower one‐fourth of the population) experience about twice the risk of cancer compared with those with high intake, even after control for potentially confounding factors.
For lung cancer, significant protection was found in 24 of 25 studies after control for smoking in most instances. Fruits, in particular, were significantly protective in cancers of the esophagus, oral cavity, and larynx, for which 28 of 29 studies were significant. Strong evidence of a protective effect of fruit and vegetable consumption was seen in cancers of the pancreas and stomach (26 of 30 studies), as well as in colorectal and bladder cancers (23 of 38 studies). For cancers of the cervix, ovary, and endometrium, a significant protective effect was shown in 11 of 13 studies, and for breast cancer a protective effect was found to be strong and consistent in a meta analysis.
It would appear that major public health benefits could be achieved by substantially increasing consumption of these foods.
Water is an essential nutrient - it is required in amounts that exceed the body's ability to produce it. All biochemical reactions occur in water. It fills the spaces in and between cells and helps form structures of large molecules such as protein and glycogen.
Most foods contain water. The body can usually get 20% of its total water requirements from solid foods alone. The human body can last weeks without food, but only days without water.
The digestion process also produces water as a byproduct and can provide around 10 per cent of the body’s water requirements.
Water is a transparent and nearly colorless chemical substance. Its chemical formula is H2O, meaning that its molecule contains one oxygen and two hydrogen atoms.
Water covers 71% of the Earth's surface. It is vital for all known forms of life. On Earth, 97% of the planet's crust water is found in seas and oceans, 1.7% in groundwater, 1.7% in glaciers and the ice caps. Only 2.5% of this water is freshwater, and 98.8% of that water is in ice (excepting ice in clouds) and groundwater. Less than 0.3% of all freshwater is in rivers, lakes.
Safe drinking water is essential to humans and other lifeforms even though it provides no calories or organic nutrients. ~One billion people still lack access to safe water. It was estimated that by 2025 more than half of the world population will be facing water-based vulnerability, and by 2030 water demand in some developing regions of the world will exceed supply by 50%.
Approximately 70% of the freshwater used by humans goes to agriculture.