[Differential health effects of alcoholic beverages: an umbrella review of observational studies.]

Background: There is great controversy about whether the consumption of different types of alcoholic beverages has different effects on health. The objective was to carry out an umbrella review of the studies that described the association between the consumption of different types of alcoholic beverages and various health indicators.

Methods: Search through PubMed (from January 2000 to February 2019) of systematic reviews and meta-analysis that reported quantitative results of the association between the consumption of different types of alcoholic beverages and health effects. 26 studies were identified: 21 related to cancer, three to cardiometabolic diseases, two to neurodegenerative diseases, and one to general mortality.

Results: The results were heterogeneous. The great methodological differences in the estimation of alcohol intake, control of confounding variables, and the evaluation of statistical difference between types of beverages, made it very difficult to conclude whether they cause an unequal effect on health. In general mortality and cardiometabolic diseases, it was suggested that beer and spirits appear to have a greater negative effect than wine, but the differences were not statistically significant. Regarding cancer, in those types where the causal evidence is totally consistent: oropharynx, colorectal and breast (women), the reviews did not show a differentiated effect according to the type of alcoholic beverages. Regarding neurodegenerative diseases, the available information did not allow clear conclusions to be drawn.

Conclusions: The reviewed evidence does not allow to conclude that the consumption of wine, beer or spirits, has a differential effect on cardiometabolic, cancer or neurodegenerative diseases.