Based on the available information, moderate alcohol use can indeed affect brain structure. According to various studies, even moderate alcohol consumption can lead to changes in the brain's white matter [1]. White matter is responsible for transmitting signals throughout the brain, and changes in its structure can impact cognitive functions such as memory, attention, and spatial ability [1].

Moreover, a study published in the journal NeuroImage found that moderate drinkers had reduced volume in the hippocampus, a brain region associated with memory and learning [2]. The study also found that moderate drinkers had increased volume in the cerebellum, which is responsible for motor control [2]. These changes in brain structure suggest that even moderate alcohol use can have a significant impact on the brain.

It is important to note that the effects of moderate alcohol use on brain structure can vary depending on factors such as age, gender, and genetic factors [3]. For example, a study published in the journal Alcoholism: Clinical and Experimental Research found that the effects of moderate alcohol consumption on brain structure differed between men and women [4].

In summary, based on the available information, moderate alcohol use can affect brain structure, leading to changes in white matter and the volume of certain brain regions. However, the effects of moderate alcohol use on brain structure can vary depending on individual factors.

Sources:

1. <https://www.drugpatentwatch.com/article/effects-of-alcohol-on-brain-structure-and-function-1017>
2. <https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3569616/>
3. <https://www.drugabuse.gov/publications/research-reports/alcohol-drugs-brain-behavior/introduction>
4. <https://academic.oup.com/alcalc/article/39/3/351/141883>