By Michael J. Critelli | MakeUsWell Newsletter,
The modern food system rests on a quiet assumption: that what is safe for adults is safe for children. Yet when we examine how studies of foods, additives, and preservatives are actually conducted, that assumption begins to look less like science and more like convenience.
Most controlled nutrition studies are performed on adults. The reasons are practical and ethical: adults can consent, their biology is more stable, and regulators impose fewer constraints. But this creates a structural gap. Children, whose bodies and brains are still developing, are exposed daily to the same additives and preservatives, yet are rarely the primary subjects in the studies used to validate their safety.
This matters because children are not simply “small adults.” Their metabolic systems process chemicals differently. Their brains are in active stages of development. Their exposure, relative to body weight, is often higher. A preservative that appears benign in a 180-pound adult may behave differently in a 40-pound child whose neurological pathways are still forming. The scientific literature acknowledges these differences in principle, but the evidence base often lags behind.
Children also have different meal and snacking habits versus adults. The content of what they eat for lunch will be constrained by what is available at school. Frazzled adults are more likely to cave in and take them to their favorite pizza place. As adolescents, they are more likely to be consuming the big cup of soda and the big vat of popcorn at a movie theater they are more likely to frequent.
California used a combination of three types of data to conclude that synthetic dyes were likely to cause higher levels of unhealthy hyperactivity. They supplemented targeted randomized controlled trials with observational and epidemiological studies, and animal testing.
Where children do appear in research, it is typically in narrower contexts. There are robust studies on infant nutrition, micronutrient deficiencies, and food allergies. The LEAP Study is a powerful example of how focused pediatric research can overturn conventional wisdom and reshape guidelines. But additives and preservatives, substances designed to extend shelf life, stabilize texture, or enhance flavor, rarely receive this same level of direct pediatric scrutiny unless researchers design a customized research process as California did.
Instead, safety assessments for additives often rely on a combination of adult human studies, animal models, and toxicological thresholds such as “acceptable daily intake” (ADI). These thresholds are then adjusted downward to account for children. While this approach is scientifically grounded, it is also inherently indirect. It assumes that scaling exposure is sufficient to account for developmental differences, an assumption that may not hold for all substances, particularly those affecting neurological or endocrine systems.
Consider common categories of additives. Artificial colorings, preservatives like sodium benzoate, emulsifiers, and flavor enhancers are ubiquitous in processed foods heavily consumed by children. Some studies have linked certain food dyes to behavioral changes in subsets of children, prompting regulatory responses in regions like the European Union. Yet in the United States, the evidence has been deemed inconclusive at a population level, and widespread use continues. This divergence reflects a deeper issue: when pediatric-specific evidence is limited or mixed, regulatory frameworks often default to maintaining the status quo.
Preservatives raise a parallel concern. Compounds that inhibit microbial growth are essential for food safety and supply chain efficiency. But their long-term, cumulative effects, especially in combination with other additives, are not well understood in children. Most studies examine single substances in isolation, while real-world diets involve complex mixtures consumed over years. The developing body is not just processing one additive at a time; it is navigating a continuous stream of exposures whose interactions are rarely studied directly.
There are also practical barriers to improving this evidence base. Conducting controlled trials in children involving dietary additives is ethically and logistically difficult. Compliance is inconsistent, parental behavior introduces confounding variables, and long-term follow-up is costly. As a result, much of what we know comes from observational studies, which can identify correlations but struggle to establish causation. This leaves both scientists and policymakers operating with partial visibility.
The consequence is a form of “evidence asymmetry.” We have high confidence in the necessity and functional benefits of additives and preservatives within the food system, but lower confidence in their long-term developmental impacts on children. Into this gap flows public concern, sometimes overstated, but often grounded in a legitimate recognition that the science is incomplete.
For business leaders and policymakers, this is not merely a scientific issue; it is a strategic one. Trust in the food system increasingly depends on transparency and precaution. Companies that rely heavily on additives face a choice: adhere strictly to regulatory minimums, or move proactively toward formulations that anticipate consumer concerns and emerging science. The latter path may involve reformulation, clearer labeling, and investment in research that includes pediatric populations more directly.
For parents and consumers, the challenge is navigating uncertainty. The absence of definitive evidence does not equate to the absence of risk, but neither does it justify blanket alarm. It calls for informed judgment: favoring whole foods where possible, being attentive to highly processed products, and recognizing that cumulative exposure, rather than any single ingredient, is likely the more meaningful lens.
Ultimately, the issue is not that additives and preservatives are inherently unsafe. It is that our systems for evaluating their safety have been built around adult models, while children live within the same exposure environment. Closing that gap will require more than incremental research. It will require a shift in how we define “safe,” from what is tolerable in the average adult to what is optimal for the developing child.