# Association Between Selected Flavanols and Isoflavones and Precocious Puberty in Girls—A Scoping Review

## TL;DR

This review explores how flavanols from green tea and isoflavones from soy may influence early puberty in girls, finding mixed evidence.

## Contribution

The study is the first scoping review to examine the potential link between green tea flavanols, soy isoflavones, and precocious puberty in girls.

## Key findings

- Polyphenols from decaffeinated green tea may lower the age of first menstruation in girls with obesity.
- Soy isoflavones show inconsistent effects, with some studies suggesting no impact and others indicating possible acceleration or delay of puberty.
- Very early soy exposure (<4 months) may be linked to earlier puberty, but evidence remains unclear.

## Abstract

Background/Objectives: Precocious puberty in girls currently appears to be one of the main problems in pediatric endocrine gynecology. Early onset of menstruation (EOM) means that the age at which the first menstruation occurs is lower than the average/median for the population, which ranges from 12 to 13 years and depends primarily on ethnic origin. Depending on age and severity of symptoms, these disorders negatively affect girls’ quality of life in many areas, including school life, family relationships, and everyday life. Methods: This article provides a scoping review summarizing scientific evidence from human studies on the association between substances derived from green tea (flavanols) and soy (isoflavones) and precocious puberty in girls. Results: Despite the relatively small number of girls enrolled in the studies, available scientific evidence from randomized controlled trials (RCTs) suggests that polyphenols from decaffeinated green tea (DGTP) may contribute to lowering the age of first menstruation in girls living with obesity. The effect of soy isoflavones or soy in the context of premature menstruation in girls is unclear. Most studies report that it may have no effect on the age of first menstruation, while individual studies suggest that very early exposure to soy (< 4 months of age) may result in earlier puberty, and others suggest that higher consumption of soy isoflavones delays this process. Conclusions: Further well-designed intervention studies in humans are needed to better understand the endocrine and metabolic relationships regarding the role and importance of specific polyphenols in the pathogenic mechanisms of the development and treatment of precocious puberty in girls.