In the alcohol episode of his podcast, Andrew Huberman discusses this study (Daviet et al 2022) that shows significant reduction of grey matter and white matter in the brain even at low levels of drinking. However, just because a difference is statistically significant, doesn't necessarily mean that it is clinically meaningful.
Look at the results in Table 2. Increasing daily drinks from 0 to 1 is associated with 0.03 standard deviations reduction in grey matter volume. I don't know how to interpret 0.03 standard deviations in grey matter volume, but it sounds like it could be very small. For example, the standard deviation of human height is about 2.5 inches, so 3% of that would be 0.07 inches -- a non-noticeable amount for pretty much any situation I can think of.
What amount of grey/white matter volume reduction meaningfully affects cognitive function? How to interpret this amount of change in grey/white matter volume?
