equivalent to the effect of aging 2 years (or 1.7 years in the model that excludes individuals who consume a high level of alcohol), where the increase from two to three daily units is equivalent to aging 3.5 years (or 2.9 years in the model that excludes individuals who consume a high level of alcohol).Table 2Predicted average additional effect (in standard deviations of IDP) of increasing alcohol intake by one daily unit on whole-brain gray matter volume and white matter volume, for models with different sets of control variables (first and second columns), and for standard control variables with samples excluding abstainers (third column) and individuals who consume a high level of alcohol (last column).Standard control variablesExtended control variablesExcluding abstainersExcluding those that consume a high level of alcoholIntake changesGlobal GMVGlobal WMVGlobal GMVGlobal WMVGlobal GMVGlobal WMVGlobal GMVGlobal WMV0–1 unit−0.030−0.020−0.038−0.017−0.019−0.015−0.034−0.0191–2 units−0.127−0.074−0.126−0.073−0.123−0.070−0.107−0.0672–3 units−0.223−0.129−0.214−0.129−0.226−0.124−0.181−0.1163–4 units−0.319−0.184−0.302−0.185−0.330−0.179−0.255−0.1640–4 units−0.699−0.407−0.682−0.404−0.699−0.388−0.577−0.367Note. IDP imaging derived phenotype, GMV gray matter volume; WMV white matter volume.Table 3Predicted equivalent effect of aging in terms of additional years for an average 50-year-old individual (model includes all participants).Standard control variablesIntake changesGlobal GMVEquivalent aging at 50Global WMVEquivalent aging at 500–1 unit−0.0300.5 years−0.0200.5 years1–2 units−0.1272.0 years−0.0742.0 years2–3 units−0.2233.5 years−0.1293.5 years3–4 units−0.3194.9 years−0.1844.9 years0–4 units−0.69910.2 years−0.40710.4 yearsNote. GMV
