A new study published in March 2025 in the journal Science reveals that antibiotic exposure during infancy can hinder the development of insulin-producing pancreatic cells, increasing the risk of Type 1 diabetes later in life.

The research underscores the crucial role of the infant microbiome, which comprises bacteria and fungi that colonize a baby's body early in life, in supporting metabolic health.

The study identifies a critical developmental window in an infant's first year when specific microbes are essential for optimal pancreatic cell development.

Mice genetically predisposed to Type 1 diabetes that were treated with the fungus Candida dubliniensis during infancy showed a diabetes incidence of less than 15%, compared to 90% in untreated mice.

The most effective microbe identified in the study was Candida dubliniensis, which promotes beta cell growth and was found in fecal samples of healthy infants aged 7 to 12 months.

Experiments demonstrated that mice given broad-spectrum antibiotics during a specific early life window equivalent to 7 to 12 months in humans exhibited reduced insulin-producing cells and poorer metabolic function as adults.

Previous studies have shown that breastfeeding and vaginal births promote a healthy microbiome, while early antibiotic use can increase diabetes risk by disrupting beneficial microbes.

The research highlights that factors beyond genetics, such as environmental experiences and early life microbiome composition, can influence diabetes susceptibility.

Hill's team is conducting research in a specialized facility at CU Boulder to study the infant microbiome and its potential health benefits, challenging traditional views on the role of germs in health.

Hill envisions future treatments involving microbe-based supplements alongside antibiotics to restore beneficial microbes that antibiotics may eliminate, though caution is needed due to potential risks in adults.

While promising, the research notes that such microbe-based treatments are not yet ready for clinical application, as beneficial microbes in childhood can pose risks in adults.

Type 1 diabetes affects over 2 million adults in the U.S. and is characterized by the pancreas's inability to produce insulin, leading to high blood sugar levels.