Long term alcohol abuse can lead to brain shrinkage (both gray and white matter), impairment of mental capacities and dementia. Conversely, moderate alcohol use seems to have positive impact on brain function.
Structural brain changes
The long-term effects of alcohol abuse on the brain are, among other things, changes in size, number and structure of neurons and loss of synapses. Results of studies on the effects of moderate or no alcohol use on brain-structure are, on the other hand, inconsistent. Some studies show that neither current alcohol intake nor total amount of alcohol consumed over a lifetime is associated with brain volume decline in moderate drinkers. Other studies have shown that the decline of brain tissue is most prominent in those who abuse alcohol and least in those who do not use alcohol, i.e. moderate drinkers who are not alcohol dependent have similar but less prominent brain damage than those who are alcohol dependent.
Numerous studies have confirmed that alcohol abuse has negative impact on cognitive functions. The opposite might be true of moderate alcohol consumption. Moderate consumption seems to have positive impact on the cardiovascular system and some researchers maintain that both vascular dementia and Alzheimer’s disease are vascular disorders. It is therefore not surprising to hear that alcohol consumption in moderation could possibly benefit cognitive performance.That is exactly what has been the result of some studies, i.e. elderly moderate drinkers show better performance on tests that measure cognitive skills than both abstainers and heavy drinkers. Some studies have found that the beneficial effect of moderate alcohol consumption for cognitive functioning applies only to women but not necessarily to men. Other studies found that this effect also applied to men, but the effect was weaker.
Alcohol consumption and Alzheimer’s disease
One research reviewed the result of 23 longitudinal studies on the association between dementia and alcohol consumption. The result showed that those who used alcohol moderately in early adulthood had decreased risk for Alzheimer’s disease later on.
Excessive alcohol use has negative impact on the progression of Alzheimer’s disease though, heavy drinkers diagnosed with mild cognitive impairment are more likely to have developed Alzheimer’s disease two years after diagnosis, than those who abstain or drink moderately. Alcohol abuse has also been associated with steeper cognitive decline in Alzheimer’s patients.
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