Is Alcohol Consumption Pattern Dependent on Prenatal Sex-Steroids? A Digit Ratio (2D:4D) Study Among University...

Area of Science:

• Endocrinology
• Behavioral Science
• Anthropology

Background:

• Prenatal sex steroids are hypothesized to influence adult behaviors, including alcohol consumption.
• The digit ratio (2D:4D) serves as a proxy for prenatal androgen and estrogen exposure.
• Previous research suggests a link between digit ratio and alcohol use, but effect sizes in non-clinical populations require clarification.

Purpose of the Study:

• To investigate the relationship between prenatal sex steroid exposure, as indicated by digit ratio (2D:4D), and alcohol consumption patterns in a student population.
• To determine the effect size and direction of this relationship.
• To explore the influence of digit ratio and body size on alcohol intake.

Main Methods:

• A sample of 258 students (169 female) had their digit lengths measured directly using calipers.
• Alcohol consumption was assessed using the Polish version of the Alcohol Use Disorders Identification Test (AUDIT), measuring total AUDIT scores and weekly alcohol intake in grams.
• Digit ratios (2D:4D) and their difference (Dr-l) were calculated.

Main Results:

• Digit ratios exhibited sexual dimorphism, with males having lower ratios than females.
• Negative correlations were observed between right 2D:4D and Dr-l with AUDIT scores and weekly alcohol consumption in both sexes.
• These correlations were stronger in males and for the right hand's 2D:4D, with effect sizes ranging from small to large (r = -0.29 to -0.69).
• In males, positive associations were found between body size (height, weight, digit length) and alcohol consumption (r = 0.21 to 0.31), but these relationships were not independent of digit ratios.

Conclusions:

• Alcohol consumption is negatively associated with 2D:4D, implying that higher prenatal testosterone and lower prenatal estrogen levels are linked to greater alcohol intake.
• The strength of these correlations varies, being strongest for the right 2D:4D and in males.
• While body size showed some association with alcohol consumption in males, this effect was not independent of digit ratio, suggesting prenatal androgenization plays a significant role in shaping alcohol drinking patterns in non-clinical individuals.