Between the 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 various health problems such as scurvy, obesity, or osteoporosis, diabetes, cardiovascular diseases as well as psychological and behavioral problems. The science of nutrition attempts to understand how and why specific dietary aspects influence health.
Fermentation of the non-colored grape pulp produces white wine. The grapes from which white wine is produced are typically green or yellow. Some varieties are well-known, such as the Chardonnay, Sauvignon, and Riesling. Other white wines are blended from multiple varieties; Tokay, Sherry, and Sauternes are examples of these. Dark-skinned grapes may be used to produce white wine if the wine-maker is careful not to let the skin stain the wort during the separation of the pulp-juice. Pinot noir, for example, is commonly used to produce champagne.
In a human epidemiological analysis by Richard Doll and Richard Peto in 1981, diet was estimated to cause a large percentage of cancers. Studies suggest that around 32% of cancer deaths may be avoidable by changes to the diet. Some of these cancers may be caused by carcinogens in food generated during the cooking process, although it is often difficult to identify the specific components in diet that serve to increase cancer risk. Many foods, such as beef steak and broccoli, contain low concentrations of both carcinogens and anticarcinogens.