New Evidence, New Outlook: Substitutions and Replacements

Updated: March 23, 2026

What happens when new evidence shows an ingredient is no longer effective—or in some cases, no longer safe? In this post, we take a closer look at what happens next and how substitutions work in the real world.

Top Takeaways:

• When new evidence shows an ingredient is unsafe, regulators may require its removal and products must be reformulated.
• If an ingredient is ineffective but still safe, it may be phased out without a formal recall.
• Every ingredient serves a purpose, so replacements must perform a similar function.
• Replacement ingredients often have less data, introducing uncertainty into safety evaluations.
• Scientists and manufacturers continue working to design safer, well-characterized alternatives.

What happens when an ingredient is no longer effective or no longer safe?

When new evidence suggests that an ingredient in foods, drugs, personal care products, or cleaning products is no longer safe and/or effective—and regulators determine it must be removed—a reformulation needs to occur.

If evidence suggests an ingredient is ineffective but still safe, regulators or manufacturers may encourage consumers to discontinue use or transition to alternative products.

Products are typically not recalled unless there is a safety concern. If evidence suggests an ingredient is harmful, manufacturers and regulators may work together to recall the product.

Do manufacturers replace the ingredient with something else?

Every ingredient in a product serves a specific purpose. When an ingredient is no longer allowed, it must be replaced with another ingredient that performs the same function.

Let’s look at a recent example: phenylephrine.

Phenylephrine is commonly found in over-the-counter cold and allergy medications, where it has been used as a decongestant. New evidence suggests it is not effective for this purpose, although it remains safe.

As a result, manufacturers may need to reformulate products containing phenylephrine with alternative ingredients that provide effective decongestion.

Can manufacturers simply remove an ingredient?

Because each ingredient serves a role, removing it without replacement often changes how the product performs.

For example, Bisphenol A (BPA) has been used in plastics to provide durability, reduce bacterial growth, and prevent corrosion in food can linings. When BPA came under increased scrutiny, manufacturers were pressured—or in some regions required—to remove it.

However, those functions still needed to be fulfilled. As a result, manufacturers turned to structurally similar compounds, such as bisphenol S (BPS) and bisphenol F (BPF), which can provide similar performance.

These replacement chemicals belong to the same class and share similar structures, metabolism, and modes of action, which is why they are able to perform comparable roles.

Is there risk in replacing ingredients?

All decisions carry risk, including substitution.

Replacement ingredients often come with more uncertainty because they may not be studied as extensively as the original ingredient. This means there may be less information available about long-term effects, environmental impact, or specific exposure outcomes.

Key areas of concern can include:

• Underestimating risk
• Incomplete environmental assessments
• Potential public health impacts

Even so, replacement ingredients still go through the risk assessment process. Over time, as more data are generated through research and real-world use, our understanding of these ingredients continues to evolve.

What are researchers and manufacturers doing to improve safety?

Researchers and manufacturers are actively working to design safer chemicals with improved safety profiles for both human health and the environment.

However, developing and evaluating new ingredients takes time. It can take years to generate the data needed to understand how a substance behaves and to ensure it meets safety standards.

Advances in technology are helping accelerate this process, allowing scientists to better model, predict, and evaluate ingredient safety earlier in development.

Can we have chemical-free products or food?

Everything is a chemical.

It’s common to think of chemicals as synthetic or harmful, but chemicals are simply the building blocks of the world around us. Water, oxygen, sugar, proteins, and DNA are all chemicals.

The periodic table of elements forms the foundation of everything we interact with—including ourselves.

Because of this, it is not possible to have chemical-free products or food. What we can do is better understand which chemicals we are exposed to and how to reduce exposure to those with higher risk profiles.

The good news.

Science is continually advancing our understanding of ingredients and their safety. As new evidence emerges, manufacturers can reformulate products and improve safety profiles.

At the same time, advances in toxicology, chemistry, and computational modeling are helping researchers design safer ingredients from the start.

As our knowledge grows, so does our ability to make informed decisions about the products we use every day.

If you have any questions about foods and ingredients, please send us an email or submit your idea to us at go.msu.edu/cris-idea.