Every year, more and more children are diagnosed with type 1 diabetes. Researchers investigated diet as a potential risk factor in developing type 1 diabetes. The results indicate that a longer breastfeeding period and introducing gluten, fruit and cow’s milk later may reduce this risk. The review emphasises the need for future studies on how diet influences the development of autoimmune diabetes.
About 28,000 people in Denmark have type 1 diabetes, but the exact cause remains undiscovered. However, the increasing incidence suggests that environmental factors may play a role in triggering or promoting type 1 diabetes. A team of researchers from the Karolinska Institutet in Sweden tried to clarify the link between diet and type 1 diabetes by combining existing studies in a meta-analysis.
“Our meta-analysis supports that breastfeeding and introducing gluten, fruit and cow’s milk later may protect against the development of type 1 diabetes. We also detected other associations, but the evidence was inconclusive,” explains first author Anna-Maria Lampousi, PhD student, Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden.
The research has been published in EBioMedicine.
No strategy to prevent type 1 diabetes
“Our study was motivated by the increasing number of children diagnosed with type 1 diabetes each year. In addition, genetic factors are known to play a major role in causation, but our knowledge about environmental factors is very limited. For this reason and because there is no strategy for preventing type 1 diabetes, our main motivation was to examine environmental factors, since these can be used for prevention, and diet is one of these. Existing literature shows that diet has been extensively discussed as a potential risk factor, but the role of environmental factors in causing the development of type 1 diabetes is still unclear,” says Anna-Maria Lampousi.
The researchers identified 96 eligible articles of almost 6,000 screened articles from medical journals to include in their meta-analysis, assessing 26 dietary factors, including breastfeeding, the age at which infants started eating various foods and prenatal and childhood exposure to foods and nutrients.
Breastfeeding and gluten introduction linked to the risk of developing type 1 diabetes
The researchers found that prolonged breastfeeding was linked to reduction in risk. The risk of developing type 1 diabetes among infants who were breastfed for at least 6–12 months was 61% lower than for other infants. In addition, the researchers found that introducing gluten, fruit and cow’s milk later and drinking less cow’s milk in childhood may reduce the risk of developing type 1 diabetes. Although the researchers observed other associations, these had low certainty.
Further studies on prevention required
Anna-Maria Lampousi explains that the potential interaction between genetic susceptibility and diet is an important topic for future studies, since it can expand the information that can be used to prevent type 1 diabetes.
“Many of the identified studies had methodological problems that affected the certainty of the evidence. Several high-quality studies are warranted in this area, preferably with a prospective design and assessing several nutritional biomarkers in addition to self-reported diet,” concludes Anna-Maria Lampousi.