Harm prevention policies must take the long view
The maintenance of brain health is central to health and wellbeing across the lifespan.1 Evidence suggests three periods of dynamic brain changes that may be particularly sensitive to the neurotoxic effects of alcohol: gestation (from conception to birth), later adolescence (15-19 years), and older adulthood (over 65 years). Highly prevalent patterns of alcohol use may cause harm during these sensitive periods, including low level prenatal alcohol exposure, adolescent binge drinking, and low-to-moderate alcohol use in older adulthood.2 Although these patterns of alcohol exposure may be associated with less harm to individuals than sustained heavy drinking, the overall burden of harm in populations is likely to be large.
From fetal development to later life, the human brain goes through several periods of dynamic change. The prenatal period is characterised by extensive production, migration, and differentiation of neurons, accompanied by substantial apoptosis.3 Adolescence is characterised by synaptic pruning and increased axonal myelination.4 Older adulthood is associated with brain atrophy, which accelerates after the age of 65 years, largely driven by decreases in neuron size and reductions in the number of dendritic spines and synapses.5 Each of these changes in neurocircuitry could increase sensitivity to the effects of environmental exposures such as alcohol..