Scientists grew tiny human lung structures in the lab to understand how fish oil supplements (omega-3 fatty acids) and vitamin D might protect babies from developing asthma. They tested different amounts of these supplements on the lung tissue and used advanced technology to see which genes were activated. Fish oil had a much bigger effect on the lung cells than vitamin D, particularly by turning on genes related to fat metabolism and reducing inflammation. These findings suggest that taking these supplements during pregnancy might help prevent asthma in children, though more research in actual people is needed to confirm this.

The Quick Take

  • What they studied: How fish oil supplements and vitamin D affect the development of human lung tissue, specifically looking at which genes turn on or off when exposed to these nutrients
  • Who participated: The study didn’t involve people. Instead, scientists used lab-grown lung tissue structures created from human stem cells. They tested 36 different samples with various combinations of supplements
  • Key finding: Fish oil supplements activated 907 different genes in lung tissue, while vitamin D only activated 23 genes. Fish oil appeared to work mainly by affecting how the body processes fats and controls inflammation
  • What it means for you: This research suggests that pregnant people taking fish oil supplements might help protect their babies from developing asthma, but this is still early-stage laboratory research. Don’t change your supplements based on this study alone—talk to your doctor first

The Research Details

Scientists created tiny lung structures from human stem cells in laboratory dishes. These structures mimic how real lungs develop in babies before birth. They then exposed these lab-grown lungs to different amounts of fish oil (omega-3 fatty acids) and vitamin D—some samples got no supplements, some got small amounts, and some got larger amounts. The lung tissue was allowed to grow and develop for 50 days, similar to how lungs develop in a growing baby.

After the lung tissue finished developing, the researchers used a powerful technology called RNA sequencing to read which genes were turned on or off in each sample. Think of genes like instruction manuals—when they’re ‘on,’ the cell reads those instructions and makes specific proteins. By comparing which genes were active in samples with supplements versus without, the scientists could understand how these nutrients affect lung development.

The study was carefully designed with multiple copies of each condition to make sure the results were reliable. This repetition helps prove that the findings weren’t just random accidents.

This research approach is important because it lets scientists study human lung development in a controlled way without testing on pregnant people, which would be unsafe. Lab-grown tissue can show us the biological mechanisms—the ‘why’ and ‘how’—behind why certain supplements might prevent disease. Understanding which genes and pathways are affected helps scientists design better treatments and understand asthma development.

This is early-stage laboratory research, which means it’s a first step but not proof that these supplements work in real people. The study used human cells, which is better than animal cells, but lab-grown tissue doesn’t perfectly match how lungs develop inside a real baby. The sample size of 36 samples is reasonable for this type of lab work. The researchers used established scientific methods and tested multiple conditions, which strengthens the findings. However, this study cannot tell us whether pregnant people actually taking these supplements will have babies with less asthma—that would require clinical trials with real people.

What the Results Show

Fish oil supplements had a dramatic effect on lung tissue, turning on or off 907 different genes. In contrast, vitamin D only affected 23 genes. This suggests that fish oil is much more powerful at changing how lung cells work during development. When lung tissue was exposed to high amounts of fish oil, two specific genes called CPT1A and ANGPTL4 became very active. These genes are involved in how the body breaks down and uses fats for energy.

When lung tissue was exposed to high amounts of vitamin D, a different gene called CYP24A1 became very active. This gene helps the body process and regulate vitamin D levels. The researchers also looked at which biological pathways were activated—essentially, which cellular ‘systems’ were turned on. Fish oil activated pathways related to fat metabolism and inflammation control, which are both important for preventing asthma.

The findings suggest that fish oil works by helping the body manage fats better and by reducing inflammation in developing lungs. Since asthma involves inflammation in the airways, this mechanism makes biological sense for why fish oil might be protective.

The study found that the dose of supplements mattered—higher concentrations had bigger effects than lower concentrations. This suggests that there may be a ‘dose-response’ relationship, meaning more supplement might mean more effect. However, the researchers didn’t test whether extremely high doses might be harmful, so we don’t know if there’s an upper limit where more isn’t better. The study also showed that different genes responded to the supplements at different times during the 50-day development period, suggesting that timing of supplementation during pregnancy might matter.

Previous studies in real people (clinical trials) have suggested that fish oil and vitamin D during pregnancy might reduce asthma risk in children. This laboratory study helps explain how that protection might work at the genetic level. However, this is the first study to directly compare fish oil and vitamin D effects on developing human lung tissue, so it adds new information to the field. The findings align with what scientists already know about fish oil’s anti-inflammatory properties, which supports the credibility of these results.

This study has several important limitations. First, it used lab-grown tissue, not real lungs developing in a baby. Lab tissue doesn’t experience all the complex factors that affect real lung development, like breathing movements, hormones, and the immune system. Second, the study only looked at gene activity, not whether the tissue actually functioned differently or whether it would prevent asthma. Third, the study used stem cells from only two sources, so results might not apply to all people. Fourth, this is a laboratory study, not a clinical trial with pregnant people, so we cannot conclude that taking these supplements will actually prevent asthma in babies. Finally, the study didn’t test whether these supplements might have negative effects at high doses.

The Bottom Line

Based on this research alone, we cannot recommend that pregnant people start taking fish oil or vitamin D supplements specifically to prevent asthma. However, if you’re already pregnant or planning to become pregnant, talk to your doctor about whether these supplements are appropriate for you. Current medical guidelines already recommend vitamin D supplementation for many pregnant people, and fish oil is generally considered safe during pregnancy. This study provides biological evidence supporting why these supplements might help, but clinical trials with real people are still needed to confirm the benefits. Confidence level: Low to Moderate (this is early-stage research).

This research is most relevant to pregnant people, especially those with a family history of asthma or allergies. It’s also important for doctors and researchers studying asthma prevention. Parents of young children might find this interesting as background information, but it shouldn’t change their current practices. People without plans to become pregnant don’t need to apply these findings to their own health right now. Anyone considering supplements during pregnancy should consult their healthcare provider, as individual circumstances vary.

If these findings eventually lead to clinical recommendations, benefits would likely take months to years to appear. Any protective effect would show up in children after birth, typically during early childhood when asthma symptoms usually develop. This is not a supplement that would provide immediate, noticeable benefits—it’s about long-term disease prevention.

Want to Apply This Research?

  • For pregnant users: Track daily fish oil and vitamin D supplementation intake (dose and type) alongside any respiratory symptoms or family history of asthma. Record the specific product names and dosages to share with healthcare providers.
  • Users planning pregnancy could use the app to set reminders for consistent fish oil and vitamin D supplementation as recommended by their doctor. The app could provide educational content about these supplements and prompt users to discuss findings with their healthcare provider before making changes.
  • For parents: Track child’s respiratory health (cough frequency, breathing difficulties, asthma diagnoses) starting from birth and correlate with maternal supplement use during pregnancy. This personal data can help identify patterns and inform future healthcare discussions. The app could generate reports showing supplement adherence during pregnancy versus child respiratory outcomes over time.

This research is laboratory-based and has not been tested in pregnant people. These findings do not constitute medical advice or a recommendation to take supplements. Pregnant people or those planning pregnancy should consult their healthcare provider before starting, stopping, or changing any supplements. This study shows biological mechanisms but does not prove that these supplements prevent asthma in real children. Individual health circumstances vary, and what’s appropriate for one person may not be appropriate for another. Always discuss supplement use with your doctor, as some supplements can interact with medications or have contraindications for certain health conditions.