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Genetic and Environmental Influences on Caffeine Intake in Korean Twins
Minsu Cho1, Jiyoung Youn2, Moonil Kang3
1Department of Food and Nutrition, College of Human Ecology, Seoul National University, Seoul, 08826, Korea.
Behavior Genetics
|July 10, 2026
Summary
Genetic and environmental factors influence caffeine intake. This study found coffee and tea drinking, and total caffeine intake, are partly heritable, with environmental factors playing a larger role.
Area of Science:
- Behavioral Genetics
- Nutritional Science
- Human Genetics
Background:
- Caffeine consumption, particularly from coffee and tea, is widespread.
- Both genetic predispositions and environmental influences are thought to affect individual caffeine intake patterns.
- Understanding the interplay of these factors is crucial for public health and personalized nutrition.
Purpose of the Study:
- To investigate the heritability of coffee drinking, tea drinking, and total caffeine intake.
- To quantify the relative contributions of genetic and environmental factors to caffeine consumption habits.
- To explore age-related variations in the genetic influence on caffeine intake.
Main Methods:
- Utilized data from 1,106 Korean twins (456 monozygotic, 97 dizygotic pairs) from the Healthy Twin Study.
- Employed structural equation modeling to estimate heritability and 95% confidence intervals (CIs).
- Analyzed variations in coffee intake, tea intake, and total caffeine consumption.
Main Results:
- Heritability estimates were 0.29 (0.21, 0.37) for coffee drinking, 0.11 (0.02, 0.20) for tea drinking, and 0.27 (0.16, 0.38) for total caffeine intake.
- Unique environmental factors accounted for the majority of variance in all measured caffeine intake traits.
- Environmental factors had a greater impact on coffee drinking than genetic factors in early adulthood, while genetic influence on tea drinking remained low.
Conclusions:
- Coffee drinking, tea drinking, and total caffeine intake exhibit partial heritability.
- Unique environmental factors are the predominant influence on caffeine consumption habits.
- Genetic contributions to tea drinking are consistently low across different age groups.
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