Pregnancy is, biologically speaking, a state of controlled upheaval. The immune system recalibrates. Blood volume surges. And sometimes, inflammation rises to unsafe levels, with potential adverse health effects for both parent and child.

A new studysuggests that choline, a nutrient many pregnant people consume too little of, may play an underappreciated role in keeping inflammation in check.

Researchers analyzed data from more than 1,300 pregnant participants enrolled in the Alberta Pregnancy Outcomes and Nutrition (APrON) cohort, one of the most detailed long-running pregnancy nutrition studies in North America. They found that higher recent dietary choline intake was associated with lower levels of inflammation in the third trimester.

"We all have these signaling proteins that can be inflammatory in our blood, but when they go beyond outside their normal range, we get worried," said first author Elisabeth Larson, a doctoral student in nutritional sciences in the College of Human Ecology. "Inflammation can be caused by anything from viral infection to chronic disease, such as obesity or cardiovascular disease, and even things like psychological stress."

Most strikingly, Larson found that participants with the highest choline intakes had dramatically lower odds of having clinically elevated inflammation than those with the lowest intakes.

Choline is an essential nutrient involved in many biological processes, including cell membrane structure, neurotransmitter production, methylation, immune cell receptor agonism, and fetal brain development, and some of these biochemical processes play a role in the regulation of inflammation. It is found primarily in eggs, meat, fish, dairy and some legumes and cruciferous vegetables.

"It's most abundant in animal-source foods," Larson said. "If you're vegetarian or vegan and not taking supplements, I would be concerned that you aren't consuming enough choline."

Despite its importance, choline remains something of a nutritional afterthought. It is not always emphasized in prenatal counseling, and many prenatal vitamins contain little or none of it. Surveys suggest that most pregnant people fall short of recommended intake levels.

That gap made the new findings especially compelling to the research team.

Using detailed 24-hour dietary recalls collected during the third trimester, the investigators estimated participants' recent choline intake and compared it with blood levels as measured by high-sensitivity C-reactive protein (hs-CRP), a widely used biomarker of low-grade systemic inflammation. The association between choline intake and CRP held even after accounting for factors known to influence inflammation - such as body mass index, gestational age, total energy intake, omega-3 fats and other nutrients involved in related metabolic pathways.

The relationship was not linear. Instead, inflammation dropped most steeply as intake rose from very low levels into moderate and higher ranges, suggesting potential thresholds rather than a simple "more is better" effect.

"We had fewer data points at the lower or higher intake ends, so we need to do more research about a potential threshold relationship," Larson cautioned.

Importantly, the researchers did not examine choline in isolation. Choline works alongside other so-called methyl donor nutrients, including folate, vitamin B12 and betaine, all of which participate in overlapping biochemical cycles.

To account for this complexity, the study tested whether choline's association with inflammation depended on intake of these other nutrients. While the biological pathways are intertwined, the inverse relationship between choline and hs-CRP remained robust across models, suggesting an independent contribution.

The results align with experimental studies in nonpregnant adults and rodents showing that higher choline intake can lower inflammatory markers. Until now, evidence in pregnancy has been sparse.

"This helps fill a meaningful gap because pregnancy has historically been excluded from interventional trials, even though it's a period of enormous physiological importance," Larson said.

The current recommendation for choline during pregnancy is 450 mg, but there's some evidence that that may not be enough, Larson said.

The findings also raise questions about whether current dietary guidelines adequately reflect choline's role during pregnancy, and whether clinicians should pay closer attention to it alongside better-known nutrients like folate and iron.

"There really isn't enough work on these under-appreciated nutrients that might be predictive of health for mother and child," Larson said. "It's important because Mom's health is very predictive of Baby's future health."