From Playgrounds to Makeup Counters: Science Behind Precocious Puberty

Authored By: Leena Jalees

It is a widespread phenomenon that children today are having accelerated childhoods,

with faster mental and physical development compared to the youth of prior generations. This is observed through the fact that most kids today seem to skip the “awkward stage” of

prepubescence, a period of time during which children lack maturity and struggle to find a sense of identity. Recently, social and cultural trends have evolved to reflect more mature concepts. This phenomenon does not just have a cultural basis, but biological roots explained by precocious puberty, especially among girls. An analysis of international studies from 1977 to 2013 showed puberty in girls has started roughly three months earlier every decade (1. Eckert-Lind, MB, 2020), with the average age at menarche (start of periods) decreasing from 17 years to 13 years from the mid-19th century to the mid-20th century (2. Prosperi, Ph.D, 2022). Furthermore, the COVID-19 pandemic has contributed to this phenomenon, indicating that influencing factors driving early puberty are recent and include exposure to endocrine-disrupting chemicals (EDCs) found in personal care products, sedentary lifestyle, increased prevalence of childhood obesity, increased levels of screen-time, and higher overall stress levels.

Personal Care Products and Endocrine Disruptors

Most personal care products accessible to pre-teens contain harmful chemicals such as

phthalates and phenols. These substances, often found in shampoos, moisturizers, and cosmetics, can interfere with hormone functions, acting as endocrine disruptors. For example, phthalates, frequently used as preservatives or fragrance enhancers, can mimic estrogen, causing early breast development in girls. Not only do these chemicals impact hormone levels, but they also disproportionately affect specific racial groups, such as Black and Hispanic girls, due to disparities in product use (3. Taylor, Ph.D, 2023).

This connection between personal care products and early puberty has recently gained

attention, especially during the COVID-19 pandemic. According to the NIH, researchers found that the pandemic further exacerbated the rise in early puberty due to sedentary lifestyle. One study highlighted that the pandemic’s lockdowns also increased children's exposure to personal care products due to the surge in screen time and social media influences, leading to higher product use among younger children (4. NIEHS, 2024). Coupled with lifestyle changes like reduced physical activity and increased stress, the pandemic created an environment where early puberty became even more common.

The Health Impacts of Early Puberty

Early puberty comes with significant health implications, both physical and

psychological. Girls who reach puberty earlier than their peers are at a higher risk of developing health problems in the future , including metabolic diseases, and reproductive tract cancers such as breast cancer, cardiovascular issues, and endocrine-related cancers. According to the National Institute of Health, “Changes in pubertal timing are related to rapid growth and reduced final adult height and to a higher risk of developing characteristics of metabolic syndrome.” Psychologically, early puberty may also be linked to “more risky behaviors, earlier sexual activity, low self-esteem, psychosocial vulnerability” (2. Prosperi, Ph.D, 2022), as bodies mature faster than emotional and social environments can support.

There are cultural implications that are just as evident. Girls experiencing early puberty

often turn to adult behaviors and consumerism at a younger age. This is where the "Sephora Kid" epidemic comes into play, referring to younger children frequenting makeup stores like Sephora, driven by earlier physical development and societal pressures to appear older. While this trend might seem superficial, it speaks to deeper biological and societal shifts. Children, especially girls, are experiencing a disconnect between the state of their bodies and external expectations, forcing them to “grow up” faster than developmentally normal.

The Role of Obesity and Lifestyle Changes

In addition to chemical exposure, lifestyle changes—especially those seen during the

pandemic—have played a role in accelerating puberty. Obesity is one significant factor. Higher body fat levels increase the production of estrogen, which triggers puberty at an earlier age. The lockdowns during the pandemic amplified these issues, with children leading more sedentary lifestyles and experiencing poor diets, further contributing to this phenomenon (5. Kogut et al., 2022). Additionally, increased screen time and artificial blue-light exposure during the pandemic was shown to disrupt circadian rhythms, another factor influencing hormone regulation and puberty onset.

Addressing Early Puberty

Addressing the rise in early puberty requires a multifaceted approach to address the

biological, environmental, and social factors contributing to the issue (6. DiPietro, 2023).

Regulatory efforts are underway to reduce the use of harmful chemicals in personal care

products, and companies are beginning to offer safer alternatives. However, the problem is far from solved. Parents, healthcare providers, and educators must stay informed about the potential risks and take proactive steps to protect children from the negative impacts This includes ensuring that beauty trends and societal standards don’t place pressure on kids to rush into adulthood prematurely and that access to products that induce precocious puberty is limited. Moreover, attention must be given to public health measures targeting childhood obesity and promoting healthier lifestyles. By encouraging balanced diets and more physical activity, parents and communities can help mitigate the risk of early puberty onset.

Ultimately, while the rise of the "Sephora Kid" may seem like a cosmetic trend, it reflects

a deeper biological shift driven by environmental and lifestyle changes (7. Acinikli, 2022). As

we continue to explore the causes behind this phenomenon, it’s crucial to consider the biological and societal factors at play to protect the health and well-being of upcoming generations.

References

1. Eckert-Lind, C., Busch, A. S., Petersen, J. H., Biro, F. M., Butler, G., Bräuner, E. V., & Juul,

A. (2020). Worldwide Secular Trends in Age at Pubertal Onset Assessed by Breast Development

Among Girls: A Systematic Review and Meta-analysis. JAMA pediatrics, 174(4), e195881.

https://doi.org/10.1001/jamapediatrics.2019.5881

2. Prosperi, S., & Chiarelli, F. (2023). Early and precocious puberty during the COVID-19

pandemic. Frontiers in endocrinology, 13, 1107911. https://doi.org/10.3389/fendo.2022.1107911

3. Taylor, K. W., Howdeshell, K. L., Bommarito, P. A., Sibrizzi, C. A., Blain, R. B., Magnuson,

K., Lemeris, C., Tracy, W., Baird, D. D., Jackson, C. L., Gaston, S. A., Rider, C. V., Walker, V.

R., & Rooney, A. A. (2023). Systematic evidence mapping informs a class-based approach to

assessing personal care products and pubertal timing. Environment international, 181, 108307.

https://doi.org/10.1016/j.envint.2023.108307

4. Weaver, J. (2024, January 1). Links between personal care products and early puberty mapped

by new tool. National Institute of Environmental Health Sciences.

https://factor.niehs.nih.gov/2024/1/science-highlights/personal-care-products-early-puberty

5. Kogut, K. R., Harley, K. G., Parra, K. L., Voss, R. W., Camacho, J., Mancenido, D., ... (2022).

Associations of Personal Care Products and Early Puberty in Girls. Journal of Endocrinology,

174(2), 203–212. https://doi.org/10.1530/JOE-22-0043

6. Di Pietro, G., Forcucci, F., & Chiarelli, F. (2023). Endocrine Disruptor Chemicals and

Children's Health. International journal of molecular sciences, 24(3), 2671.

7. Acinikli, K. Y., Erbaş, İ. M., Besci, Ö., Demir, K., Abacı, A., & Böber, E. (2022). Has the

Frequency of Precocious Puberty and Rapidly Progressive Early Puberty Increased in Girls

During the COVID-19 Pandemic?. Journal of clinical research in pediatric endocrinology,

14(3), 302–307. https://doi.org/10.4274/jcrpe.galenos.2022.2022-12-11