Are BHA and BHT Safe to Eat? Unpacking the Controversy Over Common Preservatives

Used to prevent spoilage and extend shelf life, BHA and BHT have been used in processed foods for decades, but their safety is a point of ongoing contention. We examine the question: are BHA and BHT safe to eat?

Quick Summary

BHA and BHT are controversial preservatives used in packaged foods. Conflicting regulatory statuses exist across the globe, with some studies raising health concerns, particularly from high-dose animal trials.

Key Points

• Conflicting Classifications: Regulatory bodies offer conflicting assessments; the FDA considers BHA and BHT 'Generally Recognized as Safe' (GRAS), while the National Toxicology Program labels BHA a 'reasonably anticipated human carcinogen'.

• Animal Studies Raise Concerns: Animal research, typically using high doses, has linked BHA and BHT to potential health risks including cancer, endocrine disruption, and reproductive issues.

• Limited Human Evidence: Despite concerns from animal studies, there is insufficient epidemiological data to conclusively link typical human dietary intake of BHA and BHT to cancer or other adverse effects.

• International Restrictions: Many European countries and Japan have banned or restricted BHA and BHT due to safety concerns, taking a more precautionary approach than the U.S..

• FDA Initiated Re-evaluation: In May 2025, the FDA began a long-awaited review of food additives, including BHA and BHT, which could lead to changes in their regulatory status.

• Read Labels to Reduce Exposure: Consumers can minimize exposure by reading ingredient lists and choosing whole foods or products that use natural preservatives like Vitamin E or rosemary extract.

What are BHA and BHT?

BHA (butylated hydroxyanisole) and BHT (butylated hydroxytoluene) are synthetic antioxidants added to many processed foods to prevent fats and oils from going rancid. This process of fat oxidation can cause food to develop an unpleasant odor and taste, while also compromising its nutritional value. By neutralizing free radicals, BHA and BHT significantly extend a product's shelf life, making them valuable and cost-effective tools for food manufacturers. They are common in items like breakfast cereals, baked goods, cooking oils, chewing gum, and snack foods. Beyond food, these compounds are also found in cosmetic products and food packaging.

The Controversy Over BHA and BHT Safety

The debate over the safety of BHA and BHT is a long-standing one, marked by conflicting assessments from different health and regulatory bodies.

Regulatory Conflicts and Classifications

• U.S. FDA: Since the late 1950s, the U.S. Food and Drug Administration (FDA) has classified BHA and BHT as "Generally Recognized As Safe" (GRAS) when used within specific, regulated limits. However, this classification was grandfathered in and has not been rigorously re-evaluated in decades, despite petitions and new scientific data raising concerns. The FDA initiated a review of food chemicals in May 2025, which includes BHA and BHT.
• National Toxicology Program (NTP): In stark contrast to the FDA's stance, the NTP, a division of the U.S. Department of Health and Human Services, has classified BHA as "reasonably anticipated to be a human carcinogen" for over three decades. The NTP's assessment is primarily based on animal studies showing tumor development in high-dose scenarios.
• International Bodies: Other countries and regions have taken a more cautious approach. BHA is classified as a possible human carcinogen by the International Agency for Research on Cancer (IARC), and the European Union has reviewed its potential as an endocrine disruptor. The use of BHA and BHT is often restricted or banned in many European countries, Japan, and Australia.

Animal Studies vs. Human Health

One of the central points of the controversy stems from the difference between animal studies and human exposure levels. Many of the adverse health effects observed in animal research, such as liver damage, reproductive issues, and certain cancers, occurred at significantly higher doses than a typical human would consume through food. For example, BHA has been shown to cause benign and malignant tumors in the stomachs of rats, mice, and hamsters when exposed to high dietary concentrations. BHT has also been linked to liver tumors and other organ issues in high-dose animal studies. Critics argue that even low-level, long-term exposure to these additives, especially the cumulative effect from many sources, could pose risks not captured by standard regulatory assumptions.

Potential Health Risks

Concerns about BHA and BHT are not limited to carcinogenicity. Other potential health risks have been identified in various studies, although human evidence remains limited.

Possible Health Effects of BHA and BHT

• Endocrine Disruption: BHA is a suspected endocrine-disrupting compound in the EU, and animal studies suggest it can interfere with hormone function and affect reproductive organs. High-dose BHT has also shown potential to disrupt the reproductive system in some animal models.
• Allergic Reactions: Both BHA and BHT can cause allergic reactions, particularly skin allergies, in some sensitive individuals.
• Other Toxic Effects: Studies have also linked these chemicals to immune system changes and other toxic effects at high doses, emphasizing the need for more comprehensive research.

Comparison: BHA vs. BHT

There are subtle differences in the documented health concerns and regulatory assessments for BHA and BHT.

Aspect	BHA (Butylated Hydroxyanisole)	BHT (Butylated Hydroxytoluene)
Carcinogenic Status	Classified as "reasonably anticipated to be a human carcinogen" by the National Toxicology Program. Also deemed a "possible human carcinogen" by IARC.	Has shown tumor-promoting effects in high-dose animal studies, but not classified as a known carcinogen by major international bodies.
Endocrine Disruption	Listed as a suspected endocrine-disrupting compound by the EU. Animal studies indicate interference with reproductive hormones.	The EU's SCCS concluded BHT does not raise significant endocrine concerns when within recommended concentrations. Some animal studies at very high doses show potential disruption.
Primary Use	Highly common synthetic antioxidant in cereals, snack foods, cosmetics, and food packaging.	Synthetic antioxidant used similarly to BHA in foods, but also appears in personal care products like moisturizers.

How to Avoid BHA and BHT

For those concerned about the potential risks, avoiding BHA and BHT is achievable with careful shopping habits. Here is a list of steps you can take:

• Read Ingredient Labels: This is the most crucial step. BHA and BHT must be listed in the ingredients section of packaged food and personal care products. Look for the names "butylated hydroxyanisole" or "butylated hydroxytoluene." Some products may simply list "BHA" or "BHT."
• Opt for Whole, Unprocessed Foods: Fresh fruits, vegetables, and whole foods contain natural antioxidants and do not need synthetic preservatives. Reducing your intake of processed snacks, cereals, and baked goods will naturally lower your exposure.
• Choose Organic Products: Organic food standards generally prohibit the use of synthetic preservatives like BHA and BHT. Look for the USDA Organic label.
• Support Companies Using Natural Alternatives: Many manufacturers are moving toward natural preservatives, such as vitamin E (tocopherols) and rosemary extract, to meet consumer demand for cleaner ingredients. Look for these on the label as safer alternatives.

Conclusion

The question of whether BHA and BHT are safe to eat remains complex. While regulatory bodies like the FDA historically deemed them safe at low, regulated levels, decades of animal studies and international regulatory restrictions cast doubt on their long-term health implications. As scientific research continues to investigate the potential risks associated with these preservatives—from carcinogenicity to endocrine disruption—consumer awareness is key. By understanding the potential downsides and seeking out alternative products, individuals can make informed decisions to minimize their intake of these controversial additives. As a recent FDA review is now underway, the landscape for these common food chemicals may soon change.

A Review of the occurrence, metabolites and health risks of butylated hydroxyanisole (BHA): A 2023 update

[https://www.researchgate.net/publication/370464973_A_review_of_the_occurrence_metabolites_and_health_risks_of_butylated_hydroxyanisole_BHA]

BHT (Butylated Hydroxytoluene) | Kao

[https://www.kao.com/global/en/innovation/safety-quality/ingredients-contained/bht-policy/]

BHA and BHT: Safety Concerns in Food & Cosmetics | EWG

[https://www.ewg.org/news-insights/news/2025/04/despite-health-harm-concerns-bha-and-bht-remain-food-and-cosmetics]

Frequently Asked Questions

What is the primary function of BHA and BHT in food?

BHA and BHT are synthetic antioxidant preservatives added to foods containing fats and oils to prevent them from spoiling or going rancid. By stabilizing these components, they extend a product's shelf life.

Are BHA and BHT banned in any countries?

Yes, several countries and regions, including many in Europe, as well as Japan and Australia, have banned or severely restricted the use of BHA and BHT in food due to safety concerns.

Does the U.S. FDA consider BHA and BHT safe?

The FDA has classified BHA and BHT as 'Generally Recognized As Safe' (GRAS) when used at low, regulated levels. However, this designation is decades old and has faced scrutiny for not being reassessed despite new scientific findings.

What health risks are associated with BHA and BHT?

High-dose animal studies have linked BHA to cancer and endocrine disruption, and BHT to liver tumors and other organ issues. BHA is classified as a 'possible human carcinogen' by international health bodies.

Why is there conflicting information about BHA and BHT safety?

Conflicting assessments arise because different agencies and studies weigh evidence differently. The potential effects observed in high-dose animal studies are difficult to translate to typical, low-level human consumption, leading to differing conclusions about risk.

How can I avoid BHA and BHT in my diet?

To avoid these preservatives, read ingredient lists carefully for 'butylated hydroxyanisole' or 'butylated hydroxytoluene.' Opt for whole, unprocessed foods or choose organic products, which typically avoid synthetic additives.

Are natural antioxidants a safe alternative?

Yes, natural antioxidants like tocopherols (Vitamin E) and rosemary extract are increasingly used as alternatives by manufacturers to meet consumer demand for cleaner ingredients. They serve a similar preservative function without the same level of safety controversy.