Health effects associated with alcohol consumption: a Burden of Proof study

The relationship between alcohol and health is complex, and the evidence relating alcohol consumption to various cardiovascular diseases, cancers and other conditions is evolving. Moreover, alcohol drinking guidelines vary widely. Here we conducted 16 systematic reviews across four databases and conservatively re-evaluated dose-response relationships between alcohol consumption and 20 health outcomes, analysing 843 cohort and case-control studies using the Burden of Proof meta-analytic framework. We found that levels of current alcohol consumption are associated with increased risks for cancers of the breast, colorectum, oesophagus, larynx, lip and oral cavities, pharynx, liver, stomach, pancreas and prostate, as well as pancreatitis, cirrhosis and other chronic liver diseases, lower respiratory infections, tuberculosis, and atrial fibrillation and flutter. We found J- or U-shaped relationships between alcohol consumption and type 2 diabetes, Alzheimer's disease and other dementias, ischaemic heart disease, ischaemic stroke and haemorrhagic stroke. While potential health impacts at low-to-moderate levels varied by outcome, high levels of alcohol consumption were associated with increased risk across all outcomes.