Butylated hydroxyanisole (BHA) and the related compound butylated hydroxytoluene (BHT) are phenolic compounds that are often added to foods to preserve fats. BHA Characteristics: BHA is a mixture of the isomers 3-tert-butyl-4-hydroxyanisole and 2-tert-butyl-4-hydroxyanisole. Also known as BOA, tert-butyl-4-hydroxyanisole, (1,1-dimethylethyl)-4-methoxyphenol, tert-butyl-4-methoxyphenol, antioxyne B, and under various trade names Molecular formula C11H16O2 White or yellowish waxy solid Faint characteristic aromatic odor BHT Characteristics: Also known as 3,5-di-tert-butyl-4-hydroxytoluene; methyl-di-tert-butylphenol; 2,6-di-tert-butyl-para-cresol Molecular formula C15H24O White powder How do they preserve food? BHA and BHT are antioxidants. Oxygen reacts preferentially with BHA or BHT rather than oxidizing fats or oils, thereby protecting them from spoilage. In addition to being oxidizable, BHA and BHT are fat-soluble. Both molecules are incompatible with ferric salts. In addition to preserving foods, BHA and BHT are also used to preserve fats and oils in cosmetics and pharmaceuticals. What foods contain BHA and BHT? BHA is generally used to keep fats from becoming rancid. It is also used as a yeast de-foaming agent. BHA is found in butter, meats, cereals, chewing gum, baked goods, snack foods, dehydrated potatoes, and beer. It is also found in animal feed, food packaging, cosmetics, rubber products, and petroleum products. BHT also prevents oxidative rancidity of fats. It is used to preserve food odor, color, and flavor. Many packaging materials incorporate BHT. It is also added directly to shortening, cereals, and other foods containing fats and oils. Are BHA and BHT safe? Both BHA and BHT have undergone the additive application and review process required by the US Food and Drug Administration. However, the same chemical properties which make BHA and BHT excellent preservatives may also be implicated in health effects. The oxidative characteristics and/or metabolites of BHA and BHT may contribute to carcinogenicity or tumorigenicity; however the same reactions may combat oxidative stress. There is evidence that certain persons may have difficulty metabolizing BHA and BHT, resulting in health and behavior changes. BHA and BHT may have antiviral and antimicrobial activities. Research is underway concerning the use of BHT in the treatment of herpes simplex and AIDS. References and Additional Reading This is a fairly long list of online references. While the chemistry and effectiveness of BHA, BHT, and other additives within food is pretty straightforward, the controversy surrounding health effects is hot, so several points of view are available. Where possible, I have tried to note when a site has included references for its statements. Additive Sensitivity - This is the About Allergy section devoted to the health effects of additives. Adverse Effects of Some 'Inactive' Ingredients - This table summarizes the health effects reported for dyes and preservatives, including many food colors, BHA, BHT, sodium benzoate, nitrates, nitrites, and monosodium glutamate. Allergen/Additive/Preservative Search - AllAllergy.net provides this searchable database. Either input the name of the substance or find an allergen from one of their categories. Are Your Medications Making You Sick? - Judy Tidwell's article discusses the effects of inactive ingredients in medications. Did you know BHA and BHT may be used as fillers in vitamin and mineral supplements? Bioassay of Butylated Hydroxytoluene for Carcinogenicity - This is the abstract for NTIS# PB29-8539/AS, which includes a summary of the results of the study, diagrams of BHT, and an explanation of methods and analysis. BHT for Herpes Simplex and AIDS - This site discusses the clinical applications of BHT for the treatment of herpes simplex and AIDS, toxicology and carcinogenicity of BHT, the effects of BHT on clotting, and the precautions to be used when taking BHT. Cited studies are extensively referenced. Chemical Cuisine: CSPI's Guide to Food Additives - This site includes a glossary, explanation of cancer testing, alphabetical listing of additives, and a list of additives that have been banned. Common Food Additives - CNN In-Depth provides this chart listing additives and their chemistry, uses, common products containing the additives, and reported side effects. Do Food Additives Subtract from Health? - This is a Businessweek article about the effects of additive on health. References are cited in-text. Drugs Additives Causing Side Effects - PersonalMD.com lists the text of this Reuters article. One take-home message is that defining a substance in a drug as 'inert' or 'inactive' just means the substance and presumably its metabolites don't compromise a drug's effectiveness. The substance need not be 'inert' in biochemical reactions. FDA Almanac Fiscal Year 1997 - The Center for Food Safety and Applied Nutrition provides an overview of its responsibilities; description of food safety concerns and tools for ensuring food safety; description of microbiological safety concerns and activities; chemical safety mission statement; summary of food and color additive petitions; statement on research and monitoring of pesticides and contaminants; statement on nutrition, food labeling, and food formulation; summary of cosmetics and color certification; and statement concerning industry, academic, and government partnerships. Food Additives - This 1992 Food and Drug Administration brochure answers frequently asked questions about food additives. The FAQs are very thorough, but no references are provided. Food Additives - Are They Safe? - The Cooperative Extension of the College of Agriculture & Life Sciences at the University of Arizona offers this article, which emphasizes the reasons additives are used and a list of steps that can be taken to minimize accidental exposure to contaminants. References are listed. Food Allergies - Rare but Risky - The US FDA distinguishes betweem food allergies and intolerances and identifies several additives (specifically aspartame, monosodium glutamate, sulfites, and FD&C Yellow No. 5 or tartrazine) known to cause reactions in susceptible persons. Information and suggestions of ways to avoid food reactions are given, along with links for additional information. Food and Asthma - Asthma Guide John Neil Rhoades's article includes a list of several foods and additives associated with asthma and chemical sensitivity as well as links to additional resources. Fresh Look at Food Preservatives - Judith E. Foulke, a staff writer for FDA Consumer, addresses the health issues of preservatives. In addition to an overview of preservative use and regulation, she specifically discusses BHA, BHT, and sulfites. Multiple Chemical Sensitivity Homepage - This site discusses the inability of damaged nervous tissue to metabolize specific toxins. Full text articles and links to news reports are provided. Pediatric Pharmacotherapy - The Children's Medical Center in Virginia provides this discussion of the pediatric health effects of pharmaceutical excipients (inert ingredients), including preservatives, sweeteners and flavorings, dyes and colorants, and solvents. The article is extensively referenced. Sensitivity to Additives - Allergies Guide Judy Tidwell discusses sensitivity to additives. This article includes aspartame (an artificial sweetener), benzoic acid (a preservative), BHA and BHT, cochineal extract (a natural color additive), MSG (monosodium glutamate - an additive added to enhance flavor), nitrates and nitrites (preservatives), sulfites (preservatives), and tartrazine (a color additive). Some Studies on BHT and BHA - The Feingold Association maintains this collection of links to references. Excerpts from selected articles are included. Summary of Color Additives Listed for Use in the United States in Foods, Drugs, Cosmetics, and Medical Devices - This is the US FDA comprehensive list of additives, year approved, and uses and restrictions. It isn't BHA/BHT-related, but it is a handy resource. The Feingold Association of the United States - The Feingold Association provides extensive information about the effects of petroleum-derived additives and salicylates (both natural and synthetic) on the behavior/health of susceptible persons. There are links to papers and other references as well as to information about the organization and Feingold diet. The Reaction of Butylated Hydroxyanisole and Its Metabolites with Some Arylamines: Investigations of Product Mutagenicity - This is the abstract for the Kalus, Münzner, and W.G. Filby paper.

I avoid it when possible.

See http://www.answerbag.com/q_view/17122

I've been experimenting with BHT for almost a year now in order to control my cold sore outbreaks, and have been having great success, with no side effects to report about. Most of the cases with BHT causing adverse side effects are on lab rats taking dosages that equate to a human take 70 - 200 times the recommended dosage. You could very easily die taking 200 times the recommeded dosage for Vitamin A alone! I'm documenting all my experiences at http://bht-coldsores.blogspot.com

I read about BHT and it's success with Herpes back in the early 80s when I had been recently diagnosed with Herpes cold sores AND genital herpes and was suffering from repeated (almost consistent) outbreaks that lasted weeks. Just as one almost healed I'd get another outbreak. Nothing helped... until I started using BHT and then the outbreaks started only lasting 3 or 4 days and there were long gaps between outbreaks. When I stopped using BHT they'd come back fairly quickly, so I decided to stay on a consistent dose of BHT if I had an outbreak or not. After about a year I stopped having outbreaks and about 6 months after that I stopped taking BHT. As I said, that was in the early 80s (82-84) and I've never had another outbreak of genital herpes since. I do still occasionally get cold sores on my lips, but that's usually when I'm really stressed and even then they go away quickly. I have not used BHT in at least 15 years. I know this is not scientific evidence of anything, but I would hunt down a source for BHT and take it with no worries if I were getting Herpes outbreaks on a regular basis. Also, when I was taking it often, I did a lot of research because I was concerned it might be damaging (to say this use is "off-label" is an understatement). I do remember there had been a study that seemed to link it with increased risk of cancer spreading rapidly. I found some published materials from a lead researcher in BHT that stated the research actually indicated that BHT protected against cancer IF (BIG IF) you didn't already have cancer. He said there actually was some evidence that if you DID have cancer it held the potential to speed up the spread (or perhaps it was that it blocked treatment from being effective). In either case, not a thing you'd want. So, for heaven's sake if you have any concerns you might have any type of cancer (or if you have a strong family history of it), you might want to think twice... or maybe a million times... about whether getting rid of cold sores is worth that kind of risk, even if it's small. But for me, I swear by it and there is no way anyone could convince me BHT didn't have a profound effect in taming my problems with the Herpes virus. Good luck.

What is it? A petroleum derived artificial anti-oxidant. Is it safe for human consumption? Absolutely not. In everyday food, avoid it. It can cause serious allergic reactions as well as hyperactivity, and then there's the cancer link. It is listed in a number of personal care products, but it is possible to avoid it.

BHA and BHT Butylated hydroxyanisole and butylated hydrozyttoluene are used to preserve common household foods. They are found in cereals, chewing gum, potato chips, and vegetable oils. They are oxidants, which form potentially cancer-causing reactive compounds in your body. These two closely related chemicals are added to oil-containing foods to prevent oxidation and retard rancidity. The International Agency for Research on Cancer, part of the World Health Organization, consider BHA to be possibly carcinogenic to humans, and the State of California has listed it as a carcinogen. Some studies show the same cancer causing possibilities for BHT. BHT and BHA are totally unnecessary. To avoid them read the label. Because of the possibility that BHT and BHA might cause cancer, both should be phased out of our food supply. To play it safe, phase them out of your diet.

In 1975 I met a research scientist who was working on a project commissioned by the FDA to investigate the safety/side effects of BHT/BHA. His lab rats were developing cancerous tumours at an alarming rate so he asked to shut the experiment down and publish his findings. He was asked to falsify the results and when he refused he was fired.