Physiological Effects of Alcohol

"Alcohol is neurotoxic to brain development, leading to structural hippocampal changes in adolescence,16 and to reduced brain volume in middle age.17 Alcohol is a dependence-producing drug, similar to other substances under international control, through its reinforcing properties and neuro-adaptation in the brain.18 It is an immunosuppressant, increasing the risk of communicable diseases,19 including tuberculosis.20 Alcoholic beverages are classified as carcinogenic by the International Agency for Research on Cancer, increasing the risk of cancers of the oral cavity and pharynx, oesophagus, stomach, colon, rectum, and breast in a linear dose-response relation,21 with acetaldehyde as a potential pathway.22 Alcohol has a biform relation with coronary heart disease. In low and apparently regular doses (as little as 10 g every other day), alcohol is cardioprotective,23 although doubt remains about the effect of confounders.24 At high doses, especially when consumed irregularly, it is cardiotoxic.25

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Anderson, Peter; Chisholm, Dan; and Fuhr, Daniela C., "Effectiveness and cost-effectiveness of policies and programmes to reduce the harm caused by alcohol," The Lancet (London, United Kingdom: June, 27, 2009) Vol. 373, pp. 2234-2236.
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