Researchers used a special genetic analysis method to study whether vitamins and minerals affect childhood asthma. They looked at genetic data from thousands of European children to see if 15 different nutrients—like zinc, vitamin D, and iron—could prevent or cause asthma. The study found that zinc appears to protect children from developing asthma, while the other nutrients tested didn’t show a clear protective effect. This research helps scientists understand which nutrients might actually help prevent asthma, rather than just being associated with it.

The Quick Take

  • What they studied: Whether 15 different vitamins and minerals (like zinc, vitamin D, and calcium) actually cause changes in childhood asthma risk, using genetic information
  • Who participated: The study analyzed genetic data from European children in large databases. The researchers didn’t directly test children but used existing genetic information from thousands of people
  • Key finding: Zinc showed a strong protective effect against childhood asthma—children with higher zinc levels appeared to have much lower asthma risk. The other 14 nutrients tested did not show clear protective or harmful effects
  • What it means for you: While this suggests zinc may be important for asthma prevention, this is early-stage research. Parents shouldn’t rush to give zinc supplements without talking to a doctor first, as more research is needed to confirm these findings and determine safe doses

The Research Details

This study used a special research method called Mendelian randomization, which uses genetic information to figure out if something actually causes a disease, rather than just being connected to it. Think of it like using family history patterns to prove that something really causes a problem, not just that people who have the problem also have that thing.

The researchers gathered genetic data from large databases (Open GWAS and FinnGen) that contained information about European individuals. They looked at genetic variations related to 15 different micronutrients and compared them to genetic variations linked to childhood asthma. By studying these patterns, they could determine which nutrients might actually protect against or increase asthma risk.

The team used five different statistical methods to analyze the data, which is like checking their answer with multiple calculators to make sure it’s correct. This approach helps ensure the findings are reliable and not just due to chance.

Regular studies can show that people with more zinc also have less asthma, but that doesn’t prove zinc prevents asthma—maybe healthier kids just eat better. This genetic method is special because it uses inherited traits that people are born with, which can’t be changed by lifestyle choices. This makes it much stronger evidence for cause-and-effect relationships

The study’s main strength is using genetic data from large populations, which is considered reliable evidence. However, the study only included European individuals, so results might not apply equally to other populations. The researchers used multiple statistical methods to check their findings, which increases confidence. One concern is that the study is based on genetic associations, which may not perfectly predict real-world effects in actual people

What the Results Show

The most important finding was that zinc showed a strong protective effect against childhood asthma. Children with genetic variations associated with higher zinc levels had significantly lower asthma risk. The protective effect was very strong—the odds of developing asthma dropped dramatically with higher zinc.

When researchers looked at zinc alongside other nutrients (vitamin A and vitamin C), zinc remained the only nutrient showing a protective effect. This suggests zinc’s benefit isn’t dependent on other vitamins working together with it.

The other 14 nutrients tested—including vitamin D, calcium, iron, and various B vitamins—did not show significant protective or harmful effects on childhood asthma risk. This doesn’t mean these nutrients aren’t important for health; it just means this study didn’t find evidence they directly affect asthma development.

The study tested vitamin A and vitamin C in combination with zinc. Neither vitamin A nor vitamin C showed protective effects when analyzed alongside zinc. This suggests that if zinc does help prevent asthma, it may work independently rather than requiring other nutrients to be effective. The researchers also found no harmful effects from any of the nutrients studied, meaning higher levels didn’t increase asthma risk

Previous research has shown that children with asthma sometimes have lower nutrient levels, but it wasn’t clear if the nutrients actually prevent asthma or if sick children just eat differently. This study provides stronger evidence that at least for zinc, there may be a real protective relationship. The finding about zinc aligns with some earlier research suggesting zinc supports immune system function, which could explain why it might help prevent asthma. However, the lack of clear effects for vitamin D is somewhat surprising, as some earlier studies suggested vitamin D might help with asthma

The study only included genetic data from European populations, so results might not apply to African, Asian, or other ethnic groups. The researchers couldn’t directly measure how much zinc people actually ate or how much was in their blood—they only looked at genetic factors. The study also couldn’t explain exactly how zinc might protect against asthma. Additionally, genetic associations don’t always translate to real-world benefits, so more research testing actual zinc supplementation is needed

The Bottom Line

Based on this research alone, doctors should not yet recommend zinc supplements specifically to prevent asthma in children. The finding is interesting and suggests zinc deserves further study, but more evidence is needed. Children should continue getting zinc from normal food sources (meat, nuts, seeds, dairy). If a child has asthma or asthma risk factors, parents should work with their doctor on proven treatments rather than relying on zinc supplementation

This research is most relevant to asthma researchers and doctors looking for new prevention strategies. Parents of children with asthma or family history of asthma may find this interesting but shouldn’t change their child’s diet or supplements based on this single study. Children with zinc deficiency might benefit from ensuring adequate zinc intake, but this should be discussed with a healthcare provider

This is early-stage research, so it’s too soon to expect any practical changes. It typically takes 5-10 years of additional research before genetic findings like this lead to actual medical recommendations. Researchers will likely conduct studies giving some children zinc supplements and others placebos to see if it actually prevents asthma

Want to Apply This Research?

  • Track daily zinc intake from food sources (meat, poultry, beans, nuts, seeds, whole grains) and monitor asthma symptoms or respiratory health weekly. Users could log zinc-rich foods consumed and note any changes in breathing, coughing, or asthma medication use
  • Users could set a goal to include one zinc-rich food in their daily diet (like a handful of almonds, a serving of chicken, or beans with lunch) and track whether they notice any changes in asthma symptoms over 4-8 weeks. This creates a practical habit without requiring supplements
  • Establish a baseline of current asthma symptoms or respiratory health, then track weekly for 8-12 weeks while gradually increasing zinc-rich foods. Compare symptom patterns before and after, noting any improvements in breathing, exercise tolerance, or medication needs. Share results with a healthcare provider to discuss whether changes are meaningful

This research is preliminary and based on genetic analysis, not direct testing of zinc supplements in children. Do not start giving your child zinc supplements based on this study alone. Always consult with your child’s doctor before making changes to their diet, supplements, or asthma treatment plan. This study does not replace proven asthma medications or medical care. Genetic associations do not guarantee real-world health benefits. If your child has asthma, work with a healthcare provider on evidence-based treatment options.