The updated
USDA food pyramid, published in 2005, is a general nutrition
guide for recommended food consumption.
Nutrition
is the science that studies how what people eat affects their
health and performance, such as foods or food components that
cause diseases or deteriorate health.
The field
of nutrition also studies foods and dietary supplements that
improve performance, promote health, and cure or prevent disease,
such as eating fibrous foods to reduce the risk of colon cancer,
or supplementing with vitamin C to strengthen teeth and gums
and to improve the immune system.
Between
extremes of optimal health and death from starvation or malnutrition,
there is an array of disease states that can be caused or
alleviated by changes in diet.
Deficiencies,
excesses and imbalances in diet can produce negative impacts
on health, which may lead to diseases such as scurvy, obesity
or osteoporosis, as well as psychological and behavioral problems.
Moreover,
excessive ingestion of elements that have no apparent role
in health, may incur toxic and potentially lethal effects,
depending on the dose. The science of nutrition attempts to
understand how and why specific dietary aspects influence
health.
