Key Points
- A study analyzing urinary paraben levels (MeP, EtP, PrP) in 4–6-year-old children from the Environage birth cohort found a significant association between propylparaben (PrP) and increased leptin levels—a hormone linked to fat storage and obesity—suggesting that early-life exposure to parabens may contribute to long-term metabolic disruptions and obesity risk.
- The research supports the environmental obesogen hypothesis, which posits that endocrine-disrupting chemicals like parabens—commonly found in personal care products—can interfere with hormonal regulation during critical early development stages, potentially predisposing children to obesity and related health issues later in life.
- Given the observed link between paraben exposure and elevated leptin (associated with adverse metabolic outcomes), the authors recommend re-evaluating the safety of parabens in personal care products, particularly for vulnerable populations like young children.
While exposure to environmental pollutants has long been connected to obesogenic effects, evidence in young children remains sparse. Parabens, widely used as antimicrobial preservatives in personal care products, are suspected of disrupting satiety hormones during early life and potentially influencing long-term metabolism and weight regulation. A joint study between Hasselt University (Diepenbeek, Belgium), the University of Liege (Liege, Belgium), and Imperial College (London, United Kingdom) conducted a cross-sectional study analyzing urinary methyl, ethyl, propyl, and butylparaben (MeP, EtP, PrP, BuP) levels in 4–6-year-old children from the Environage birth cohort using ultra-performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS).A paper based on their research was published in Environmental Research (1).
The Environage birth cohort study was designed to carry out prospective epidemiological follow-up as from the newborn stage for the attaining of evidence on the interactions between participants and environmental exposures with processes of aging including mitochondrial function, telomere length, epigenetic mechanisms and DNA repair as the core axis of aging.
The increase in childhood obesity has surged dramatically over the past four decades across the world, mirroring the rise in adult obesity (2); its presence predisposes children to long-term health issues such as cardiovascular and metabolic diseases in adulthood (3,4). The environmental obesogen hypothesis was recently introduced, proposing that the exposure to endocrine-disrupting synthetic chemicals in personal care products during prenatal or early life stages possibly predisposes individuals to increased fat storage and obesity (5,6).
For over a century, parabens (defined as organic compounds that are commonly used as preservatives in pharmaceutical and cosmetic products [7]) have been used as low-cost antimicrobial agents (8,9). As a result, absorption through the skin forms the primary exposure route for parabens (10), with internal exposure to different paraben esters in European children is estimated to be between 0.20 and 1.01 mg/kg bw/day (11). Since the early 2000s, there has been concern expressed regarding parabens and their endocrine-disrupting properties (12–15), suggesting that widespread exposure to these compounds may contribute to the rising metabolic epidemic (16,17).
In this study, more than 96% of the BuP measurements were below the limit of quantification, the researchers state that only the values of MeP, EtP, and PrP were used by the research team for their statistical analysis. A discovered doubling in PrP was associated with an 5.34% increase in leptin (a peptide hormone released from adipose tissue and encoded by the obese (ob) gene [19]), and Bayesian kernel machine regression (BKMR) indicated a positive linear association between parabens and leptin. Additional sensitivity analyses were indicative of sex-specific differences in the relationship between parabens, body mass index (BMI), and leptin levels (1).
While leptin is primarily involved in regulation of body fat stores, its chronic elevation is associated with adverse metabolic outcomes, leading the researchers to believe that theirfindings may point to leptin as a biological mechanism linking parabens with the growing obesity epidemic in children. Given these results, the researchers state that the reassessment of the safety of parabens in personal care products, particularly for young children, warrants consideration (1).
References
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