It’s snack time, and after a long day, you’re excited to kick back with some cheese, crackers and maybe even a glass of wine. As you pick up your favorite pantry–stable items, you notice that the wrapper on your crackers is slightly unraveled. A test bite confirms what you’ve been thinking: The crackers have gone stale, which could mean more than just an off-putting taste. After successfully preparing another pantry–friendly snack, you may have found in another food what likely kept your crackers nice and crunchy before they turned stale: a common preservative called tert-butylhydroquinone, or TBHQ. More than likely, air seeped into the open bag of your crackers and rendered TBHQ’s protective properties ineffective. Although it is used in plenty of everyday food products, you probably have not heard of TBHQ. Read on to learn more about its function, safety and impact on your body.
TBHQ’s Function in Food
TBHQ is a common antioxidant that prevents fat oxidation. Oxidation can cause the foods to lose flavor, change color and deplete their nutritional value. Since oxidation can lead to fats turning rancid, TBHQ can also help increase shelf life and reduce the amount of food waste from food spoilage. You’ll often find TBHQ in foods like crackers, fats and oils, chips, donuts, some breads, popcorn, other snacks, pre-made frozen foods and packaged dinners. The U.S. Food and Drug Administration (FDA) classified TBHQ as Generally Recognized as Safe, or “GRAS,” and approved its use in foods in 1972. This decision came as pre–made foods were becoming increasingly popular. Today, many people rely on pre–made foods in some way over the course of their day, and food manufacturers use preservatives like TBHQ to keep foods from going bad as they are transported and stored in freezers, refrigerators, and on store and household shelves. Stored fats and oils, along with foods that contain these ingredients, can become moldy, stale or simply unappetizing over time, and TBHQ’s antioxidant properties help preserve those fats and oils by eliminating their oxygen content.
Is TBHQ Safe?
While there were some concerns in the 80s and 90s about high doses of TBHQ causing precancerous tumors in animal models, a 2004 European Food Safety Authority (EFSA) 2004 Panel found that TBHQ is not carcinogenic. As such, TBHQ has been approved by leading regulatory and health organizations around the world such as EFSA, the U.S. Food and Drug Administration (FDA) and the Joint FAO/WHO Expert Committee on Food Additives (JECFA). In addition, as part of the FDA’s Federal Food, Drug, and Cosmetic Act, all food additives must undergo scientific and regulatory review before receiving FDA approval. Scientists use research and testing to determine preservatives’ safety. Extensive review helps determine if additives can be safely used in foods, are safe in the human body, and have health implications. Once the FDA approves a preservative, scientists set guidelines for 1) the amount that can be safely included in foods and 2) the maximum amount people should consume. The FDA has determined that a food’s TBHQ content should not account for more than 0.02 percent of an item’s total fat and oil content. For consumers, the acceptable daily intake (ADI) is 0.7 mg/kg body weight. This limit is agreed upon internationally—the European Food Safety Authority confirmed the same ADI in 2004.
Balance and moderation are important when consuming foods with TBHQ. This preservative certainly has its pros: It helps keep everyday food items from becoming stale, rancid and spoiled. TBHQ also helps foods last longer on store shelves, thus increasing our access to quick, affordable food options and even helping reduce food waste. It’s also important to prioritize nutrient-dense whole foods like fruits and vegetables, lean protein, unsaturated fats and whole grains and be mindful of the number of processed foods you eat. Again, according to the FDA, it’s safe to consume up to 0.7 mg/kg of body weight of TBHQ per day—but it can be difficult to determine the exact amount of TBHQ you’re consuming, especially when food labels don’t detail the amount of TBHQ in their products.
This article was written by Casey Terrell, MPH, RD.
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