Sydney, Australia—A fiber-rich diet may reduce risk of preeclampsia,according to a new studyfrom researchers at several universities in Australia.

A press release regarding the study notes that plant-based fiber is broken down in the gut by bacteria into factors that influence the immune system. Specifically, preeclampsia, the study found, is heavily associated with reduced levels of acetate—which is mainly produced by fiber fermentation in the gut. Preeclampsia is characterized by high blood pressure, protein in the urine, and severe swelling. It also interferes with the child’s immune development in the womb, specifically by affecting the development of the thymus, according to the current study.

The thymus generates T cells, associated with the prevention of allergies and autoimmune conditions. These cells remained lower in infants whose mothers were preeclamptic, even until they were four years old. The current study found that acetate is central to the development of the thymus. Thus, mothers who eat too little fiber end up producing too little acetate to properly develop the fetus’s thymus and associated immunity.

Senior author of the study Professor Ralph Nanan, from the University of Sydney School of Medicine and Charles Perkins Center, noted in the release: “The mother’s gut bacteria and diet appear to be crucial to promoting a healthy pregnancy.” The recommendation to eat real food, mostly plants, he added, might be one of the most effective primary prevention strategies for some of the most serious conditions of our time.

The study noted that, as Western diets become increasingly dominated by low-fiber foods, this may explain the increase in allergies and autoimmune conditions.