Part 2: A Closer Look at the Debate Around the Danish Study
In a previous blog post, we shared findings from a major Danish study that followed 1.2 million children over 23 years to explore whether aluminum exposure from vaccines and infant formula was linked to long-term health issues like asthma, autoimmune disease, or neurodevelopmental disorders.
The study’s conclusion was straightforward: no association was found between early-life aluminum exposure and increased risk for more than 50 health outcomes.
But that wasn’t the end of the story.
Since its publication, the study has drawn attention, not just from mainstream media, but from Robert F. Kennedy Jr., who raised concerns about how the data was analyzed and whether key findings were left out of the initial conclusions.
So what’s a parent to do when experts (on all sides) disagree?
Let’s walk through what’s being said, and how to cut through the noise when information conflicts.
What RFK Jr. Is Saying
RFK Jr. criticized the study’s authors, suggesting that the conclusions published may have downplayed associations between aluminum exposure and certain neurodevelopmental disorders.
He pointed to the supplementary data (additional data not featured in the main paper) which he says suggest an increased risk of neurodevelopment disorders in children with higher levels of aluminum exposure.
These claims have sparked a wave of debate online, especially with people who are already skeptical of vaccine safety.
How the Researchers Responded
Anders Hviid, who led the Danish study, responded to RFK Jr. by acknowledging that study design choices are fair to question, but firmly rejecting the idea that the research was misleading.
Here’s what he laid out:
- Study choices were deliberate, not deceptive. Decisions about which data to include, how to set age cutoffs, and which outcomes to track were based on established scientific methods.
- The design followed prior research. His team modeled their work after an earlier U.S. study that once found a possible link between aluminum and asthma — but they couldn’t replicate that result in the Danish data.
- The research was independent. He clarified that the Statens Serum Institut (SSI) is Denmark’s national public health institute, not a vaccine manufacturer. Funding he received from outside organizations had nothing to do with vaccines.
- His conclusion hasn’t changed. He maintains that the study does not support a link between aluminum-containing vaccines and increased risk for early childhood health issues, and rejects claims that the study was designed to find “no harm.”
What Is Supplementary Data, and Why Does It Matter?
In large studies, it’s common to publish the core results in the main paper or press release, with more detailed findings placed in supplementary materials. While this additional information isn’t always highlighted, they’re still publicly available to researchers and readers.
Because supplementary data often contains more specific breakdowns, it’s possible for different people (even well-qualified experts) to interpret it in different ways.
In this case:
- The study’s authors emphasized the overall finding of no consistent link between aluminum exposure and illness.
- Critics believe certain results in the supplementary data deserved more attention and may tell a different story.
Both perspectives are looking at the same data, they’re just prioritizing different parts of it.
So Who’s Right and How Do Parents Find the Truth?
That’s the hard part — and also why conversations like this matter.
We’re not here to tell you who’s right. We’re here to say: when credible voices disagree, it’s a signal to look deeper, ask more questions, and read beyond the headlines.
Here are a few ways to keep your footing when the conversation gets heated:
- Read beyond the headline. Media, social or mainstream, is designed to grab attention. The full story often lives in the details.
- Look at the study design. Was it peer-reviewed? Was there a large sample size? What did they focus on or ignore?
- Consider the motivations — on all sides. Everyone has motivations. Whether it’s activism, institutional funding, or personal branding. That doesn’t automatically discredit anyone, but it’s worth keeping in mind.
- Ask: Does this apply to my child? Not every risk, exposure, or finding is one-size-fits-all.
Final Thoughts
As a parent, it’s normal to feel confused, or even frustrated, when experts disagree on something as serious as your child’s health. But disagreement isn’t always a sign of corruption or conspiracy. Sometimes, it’s the sign of science doing what it’s supposed to do: ask hard questions, test assumptions, and refine understanding over time.
Science rarely offers a neat “mic drop” moment. More often, progress comes through debate, review, and careful examination of the facts.
At Advocates for Healthy Kids, our mission remains the same: to bring you balanced, well-sourced information that helps you parent with confidence. Whether new research confirms safety or sparks debate, we believe you deserve access to the full conversation — not just the loudest voices in your feed.
Because in the end, you’re the one doing the research, weighing your options, and choosing what’s best. You know your child better than anyone else — and we’re here to help you trust that.