What the mixture gap means
Safety thresholds are usually set for a single substance. In practice, people consume additives in combinations across meals, beverages, and packaged foods.
Mixture research asks whether combined exposure changes the risk profile compared to single-chemical tests.
Traditional toxicology relies on the assumption that if each component is safe on its own, the mixture will also be safe, but this is being increasingly questioned.
Why testing in isolation is the standard
The current regulatory framework was built decades ago, prioritizing the assessment of individual chemicals to simplify the approval process.
Testing every possible combination of additives would be an impossible task given the thousands of approved substances in the food supply.
As a result, most safety data reflects a simplified version of reality that doesn’t account for the complexity of modern processed diets.
What the evidence suggests
Mixture studies have reported effects that are not captured by single-additive assessments.
Examples include behavioral outcomes in children and changes in cellular models when additives are combined.
Some research indicates that certain additives can enhance the absorption or toxicity of others when consumed simultaneously.
- The Southampton study tested mixtures of colors with sodium benzoate and observed increased hyperactivity in children.
- In vitro tests found stronger inhibition of neurite outgrowth when additives were combined.
- Emerging data suggests that certain emulsifiers might alter the gut barrier, potentially increasing the systemic exposure to other additives.
Children’s vulnerability
Children have higher intake per body weight and critical windows of development.
This section focuses on why mixture effects can matter more for younger populations.
Because children’s bodies are still forming, they may be less capable of detoxifying certain combinations of chemicals compared to adults.
How PRūF uses this insight
PRūF highlights additive presence and context rather than treating each additive as a stand-alone risk score.
We focus on transparency so users can make informed choices when multiple additives show up together.
Our database is designed to show you the cumulative profile of a menu item, helping you see the "cocktail effect" in real-time.
Frequently Asked Questions
The "cocktail effect" refers to the potential health impacts that arise from consuming multiple additives together, which may be different or stronger than the effects of each additive alone.
While individual additives are regulated, there is currently no comprehensive regulatory requirement for testing the safety of the specific mixtures found in processed food products.
Reducing the consumption of ultra-processed foods that contain long lists of ingredients is the most effective way to minimize exposure to unknown mixture effects.
Related pages
Sources
- Food additives and hyperactive behaviour in 3-year-old and 8/9-year-old children in the community — McCann D, et al. The Lancet (2007).
- Synergistic interactions between commonly used food additives in a developmental neurotoxicity test — Lau K, et al. Toxicological Sciences (2006).
- Children’s Vulnerability To Toxic Chemicals: A Challenge And Opportunity To Strengthen Health And Environmental Policy — Landrigan PJ, Goldman LR. Health Affairs (2011).
- Combined Exposures and Mixtures (CEM) + PRIME programs — National Institute of Environmental Health Sciences (NIEHS).
Summaries are educational and may be updated as regulations change.