Wine contains phenolic compounds (polyphenols) which give wine its characteristic colour and flavour and are produced by plants in response to fungal infection, ultraviolet light, and various chemical and physical stressors, especially during ripening. They are extracted from the seeds and skins of grapes during fermentation of winemaking, when the juice is in contact with the grape skins and seeds. The amount of polyphenols in red wine is generally greater than white wine because the red juice has longer contact with the grape skins during fermentation enabling more phenolic substances to be extracted into the red juice.
There is evidence that certain polyphenols, such as resveratrol, anthocyanins, flavonols and catechins in wine provide health benefits. Furthermore, rather than polyphenols themselves, their metabolites might be the real key players in cardiovascular and cancer protection. Researchers have shown that these polyphenols in wine act as antioxidants and are five times more potent than the benchmark antioxidant, vitamin E. These antioxidants are believed to reduce the damage caused by the body's free radicals (toxic waste products) which contribute to causing degenerative diseases in the body such as cancer, Alzheimer's disease, Parkinson's disease and ageing.
The polyphenols may also aid in inhibiting the oxidative transformation of ‘bad’ LDL cholesterol and thus, preventing the accumulation of this oxidised LDL cholesterol in the artery wall which eventually could block the blood flow and cause a heart attack or stroke.
These findings support the overwhelming and still growing body of scientific research indicating that moderate consumption of alcoholic beverages is associated with lower levels of coronary heart disease as well as with better health and lower mortality, especially when consumed in combination with a healthy diet.
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