A study by scientists from the Institut Pasteur and Inserm reveals that maternal intake of dietary emulsifiers can negatively impact the gut microbiota of their offspring. These microbiota changes may significantly increase the risk of chronic inflammatory gut disorders and obesity in adulthood. The findings were published in Nature Communications.
Emulsifiers and Their Prevalence in Foods
Food manufacturers widely use emulsifiers to improve texture and extend the shelf life of processed foods, including dairy products, baked goods, ice creams, and some powdered baby formulas. Despite their prevalence, researchers know little about their effects on human health, particularly on the intestinal microbiota.
The Study Design
Led by Benoit Chassaing, Inserm Research Director and Head of the Microbiome-Host Interactions Laboratory, the researchers exposed female mice to two common emulsifiers—carboxymethyl cellulose (E466) and polysorbate 80 (E433)—for ten weeks before gestation and continued exposure throughout pregnancy and lactation.
The team then analyzed the gut microbiota of the offspring, who had never directly consumed emulsifiers, to assess maternal influence.
Key Findings: Early Microbiota Alterations
The study found that offspring of mothers exposed to emulsifiers exhibited significant gut microbiota changes from the first weeks of life. These changes occurred during a critical period when mothers transmit part of their microbiota to their young through close contact.
Alterations included:
- Increase in flagellated bacteria, which can activate the immune system and trigger inflammation
- Closer bacterial contact with the gut mucosa, resulting in premature closure of passages that normally allow bacterial fragments to communicate with the immune system
Long-Term Health Consequences
The premature closure of these passages disrupted the communication between the microbiota and the immune system, leading to an exacerbated immune response and chronic inflammation in adulthood. Consequently, these offspring showed increased susceptibility to inflammatory gut disorders and obesity, even without direct emulsifier consumption.
Implications and Future Research
“This study highlights the importance of understanding how maternal diet influences future generations’ health,” said Benoit Chassaing. He emphasized the need to regulate food additives, especially in powdered baby formulas, which are consumed during a critical period for microbiota development.
The research team plans to continue with clinical trials to study mother-to-infant microbiota transmission, investigating both maternal nutrition with or without additives and direct infant exposure through baby formulas.