Native Hawaiian scientist Alika Maunakea of the University of Hawaiʻi at Mānoa John A. Burns School of Medicine (JABSOM) has spent more than 20 years studying epigenetics–—how environment shapes health across generations. With colleague Monika Ward of JABSOM and the Yanagimachi Institute for Biogenesis Research, they examined how maternal obesity before pregnancy may influence autism risk.
Related UH News story: UH study links maternal obesity to autism-like traits in offspring
Q: What motivated this research, and what did you discover?
We were struck by the worldwide rise in autism and by data showing that mothers who are obese face a 50–60% higher risk of having a child with autism. What wasn’t clear was when that risk takes hold—is it during pregnancy or even before? In our study, we found that maternal obesity before conception was enough to increase the likelihood of autism-related traits in offspring, at least in our mouse model. That finding points to an important window of time that hasn’t received much attention.
Q: How confident are you that these findings translate to humans?
While our work was done in mice, many of the same genetic pathways we studied are conserved in humans. What’s striking is that autism-related genes known to raise risk in people were also affected in the mouse model, not by mutations but by epigenetic changes that altered gene expression. So while it’s not proof, it strongly suggests that similar mechanisms could be at play in humans, and that gives our findings real relevance.
Q: Does obesity guarantee autism risk for a child?
No, it’s important to stress that obesity is not a determining factor. In our study, even among mice with obese mothers, about 60% developed normally. What maternal obesity does is raise the risk, which is very different from guaranteeing an outcome. That nuance matters, because it shows there’s room to intervene and reduce risks rather than assuming outcomes are fixed.
Q: What does this mean for timing—before vs, during pregnancy?
We’ve long known pregnancy is a critical period, but our study highlights that the preconception window is just as important. Health status before pregnancy can shape risks for children, not just for autism but also for other chronic conditions. This means lifestyle changes made even before planning a pregnancy, such as improving diet, exercise and overall metabolic health, may help improve outcomes for both parent and child.
Q: Is it ever too late to make lifestyle changes?
No. The message is that any step to improve health is worthwhile. Even outside the context of pregnancy, better diet and exercise lower risks for chronic disease. But when we’re talking about planning a family, those same changes may also lower risks for future children. So the preconception period is a powerful window of opportunity, but positive changes at any stage are valuable.
Q: Where does the research go from here?
The next step is to see whether improving health before conception can actually lower the autism risk we observed, and whether those benefits extend across multiple generations. We also found that male offspring were more affected than females, so we want to explore why that is and how long these effects last. These are unanswered questions with big implications for human health.
Q: How should the public understand this research?
Most importantly, this isn’t about blame. Obesity is shaped by many factors, like access to healthy foods, safe places to exercise, and healthcare resources. Our work shows opportunities where supportive policies, healthcare guidance, and community programs can make a difference. Beyond autism, improving metabolic health before conception is simply good practice for lifelong health, both for parents and for their children.
Q: How does Native Hawaiian knowledge influence your work?
As a Native Hawaiian epigeneticist, I draw inspiration from our ʻike kupuna (ancestral knowledge). For centuries, Hawaiians understood that pregnancy timing and environment shape a child’s health. For example, a saying advises strengthening the unborn child through diet and herbal remedies, an early recognition that what mothers do before and during pregnancy can affect future generations. Our research in epigenetics reflects that same idea: the environment can influence health outcomes long before birth.
