What is brominated vegetable oil, and why did the FDA ban it in food?

On Tuesday (July 2), the Food and Drug Administration (FDA) announced that it will no longer allow brominated vegetable oil (BVO) in food or beverages due to safety concerns. 

But what is BVO, and what is it found in?

BVO is vegetable oil modified with bromine, a naturally occurring chemical element that's dark-reddish-brown and liquid at room temperature. Bromine is denser than water and sinks when added to it, and when combined with a vegetable oil, the element makes that oil denser than water. This effect makes BVO useful for emulsifying certain ingredients in water, ensuring that they're evenly distributed throughout the liquid and don't separate from it.

In the past 50 years, BVO has primarily been used to help stabilize citrus flavorings within sodas, sports drinks and energy drinks. That said, many U.S. beverage makers have already replaced the BVO in their products, and "today, few beverages in the U.S. contain BVO," according to the FDA. 

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Manufacturers started using BVO in food in the 1920s, prior to the FDA's establishment. The agency initially added the modified oil to its list of foods that are "generally recognized as safe" (GRAS). However, in the 1960s and 1970s, the oil's safety came into question as animal studies suggested that consuming the product might harm the heart. 

These early studies, however, fed the animals doses far beyond what humans would be exposed to, and later studies overturned the idea that BVO hurts the heart. But nonetheless, at the time, the FDA moved to limit the use of BVO. In the late 1960s, the oil lost its place on the GRAS list and was restricted to being used as an additive in very small amounts — 15 parts per million. 

In recent years, technologies improved and enabled the FDA to undertake better studies of the concentration of BVO in drinks and of the effects of the oil on lab animals. The animals were fed amounts of BVO that mimicked the real-life exposure a human might realistically experience.

A study published in 2022 showed that rats fed BVO accumulated high amounts of bromine in their blood and tissues, and breakdown products of the oil accumulated in various organs and in fat. The particularly concerning finding was that high doses led to enlargement of cells in the thyroid, a hormone-making gland in the throat. These effects on the thyroid can lead to conditions such as goiter, which is sometimes accompanied by the thyroid making too much or too little hormone. 

Following studies such as this, the FDA proposed that BVO should no longer be allowed in food. "Animal and human data, including new information from recent FDA-led studies on BVO, no longer provide a basis to conclude the use of BVO in food is safe," the agency stated.

The newly finalized rule will take effect Aug. 2, after which companies will have one year to reformulate, relabel and deplete their inventory of BVO-containing products. Many companies have already phased out BVO in their products, and some — such as Keurig Dr Pepper, the maker of Sun Drop soda — told news outlets last year that they were moving to drop the additive.   

"The removal of the only authorized use of BVO from the food supply was based on a thorough review of current science and research findings that raised safety concerns," Jim Jones, the FDA's deputy commissioner for human foods, said in a statement. 

"We will continue to monitor emerging evidence on the chemicals we have targeted for reassessment," he said, "and in cases such as this, where the science no longer supports continued authorized use, we will take action to protect public health."

When used in products, BVO must be listed as an ingredient on the label, either as "brominated vegetable oil" or as the specific oil that has been brominated, such as "brominated soybean oil."

You might hear bromine poisoning mentioned in relation to BVO. However, this type of poisoning most often happens when people inhale too much bromine — for example, when they're working in an environment with a lot of the element. Bromism, another bromine-related condition, is caused by chronic exposure to the element. This condition was more common when people used bromine as a sedative. There is only one known case in which a person seemingly got bromism from excessive soda consumption, so this is an extremely slim risk.

This article is for informational purposes only and is not meant to offer medical advice.

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