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BHA and BHT: A Case for Fresh?

Preserved food sure is convenient, but is there a health cost?


cereal aisle

More than 80,000 chemicals are produced, used
and present in the United States. These are some of their stories.

Preserved food sure is convenient, but is there a health cost?

A Stroll Down the Aisle of a Typical Convenience Store

Convenience is a big part of our modern lifestyle, and that is not less true when it comes to food and drink. We choose disposable bottles over refillable ones. Our grocery stores (and especially our so-called convenience stores) are filled with foods designed to have long shelf lives so that they stay “fresh” on both the stores’ shelves and our own until we get around to consuming them.

What makes all this food-and-beverage convenience possible? Often times synthetic chemicals. Artificial sweeteners like acesuflame potassium (Ace-K) give reduced-calorie foods a longevity boost. BPA liners prevent canned goods from taking on a metallic tinned flavor.

The good news is that these chemicals definitely do their job extending the shelf life of food. But they are not without a potential downside: These very same chemicals may be affecting our health in unintended ways. We’ve already posted about the potential health effects of Ace-K and we and many, many others have written about the dangers of BPA. Today we look at two common preservatives you may want to consider with a wary eye.

BHA and BHT

Chances are, if you read labels, you’ve come across the acronym BHA or BHT or even both on the same label. They are preservatives commonly found in foods. What kinds of food? You name it: cereals, gum, fast food, processed potatoes, drink mixes, shortening, snack foods, and so on. The compounds are also found in food packaging, animal feed, cosmetics, pharmaceuticals, rubber, and plastics.

BHA or butylated hydroxyanisole [pdf] is a synthetic antioxidant that is used to prevent fats in foods from going rancid and as a defoaming agent for yeast. First synthesized in the late 1940s, the compound began being used as a food additive around 1947.

BHT or butylated hydroxytoluene [pdf] also stabilizes fats and is used to retain food smell, color and flavor. It too appeared on the synthetic chemical scene in the late 1940s and was used as a food additive beginning in 1954 [pdf]. (See also here.)

How Safe Are These Preservatives?

Given their near ubiquity in our processed foods, it is reasonable, indeed prudent to ask: Are BHA and BHT safe? Here’s what we’ve been able to discern.

The scoop on BHA is a bit ambivalent. The Food and Drug Administration considers it “generally recognized to be safe” or GRAS, the government’s standard for safety as a food additive and preservative. It’s been approved for use in various foods up to 0.02 percent or 200 parts per million of the fat or oil content of the food product with a couple exceptions. For dry foods like cereal the FDA has set limits for each food type. (See here and here.) All well and good, but some laboratory studies have shown BHA to be carcinogenic in rats and and other animals [pdf], and the National Institutes of Health’s National Toxicology Program concludes [pdf] that BHA can be “reasonably anticipated to be a human carcinogen.”

The situation is much the same in Europe. BHA is an approved food additive and is also considered “possibly carcinogenic to humans (category 2B)” [pdf] by the International Agency for Research on Cancer (IARC). And the European Commission has placed BHA as a category 1 potential endocrine disruptor [pdf] based on evidence that it interferes with hormone function in at least one living organism.*

The evidence on BHT is a bit more reassuring. Despite its structural similarity to BHA, there is no conclusive evidence that it is carcinogenic. The IARC lists it as unclassifiable for humans, but finds that there is limited evidence that it causes cancer in animals. (Seeherehere [pdf] and here.) Some data suggest that BHT also acts as a weak endocrine disruptor, and may impact such organs as the lungs, liver, kidney and thyroid.

A Possible Benefit?

Here’s an interesting twist. We’re all worrying about whether BHA and BHT are doing us harm. Turns out there may actually be a health benefit. These preservatives work because they are antioxidants. Foods rich in natural antioxidants are powerhouses for the body, acting against so-called free radicals that can wreak havoc on the body. So are the antioxidant properties in BHA and BHT just as good? Well, certainly the chemical preservatives do not carry the same nutritional value as foods naturally rich with antioxidants. And yet, while BHA and BHT are tumor promoters, their antioxidant properties may at the same time empower them to be protective against cancer and other infections — BHA and BHT “may be anticarcinogenic at current levels of food additive use.”

It’s a conundrum. The FDA says BHA is safe (at least at the levels they prescribe for foods), but data from the National Toxicology Program says it’s likely a carcinogen, while other researchers have concluded that it may actually be an anticarcinogen. So what’s a consumer to do? There are those, such as here, here and here, that will advise you to steer clear of both BHA and BHT; indeed, the Center for Science in the Public Interest gives BHA its “avoid” label and BHT its “caution” label. And it’s certainly true that there are alternatives. For example, here’s a radical idea: eat fresh food or at least food without artificial preservatives. And there are natural food preservatives such as vitamin E that could be used instead of BHA ad BHT.** And if you’re concerned about losing the potential antioxidant benefit of the artificial chemicals, there are more natural ways of juicing up on antioxidants — here’s WebMD’s list of 20 foods rich in antioxidants.

When it comes to my own diet, I have to confess I ingest my share of both BHA and BHT. And yet, I think that BHA and perhaps even BHT carry some risk. What better time of the year than now for me to resolve to go cold turkey on artificial preservatives? It may be the right time of year, but I don’t see a BHA- and BHT-free diet on my resolution list. I am too strongly tied to the convenience of processed foods. But I will resolve to read the labels and limit my intake and aspire to a fresher, more natural diet in the nebulous future. How about you?

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End Notes

* TBHQ or t-butylhydroquinone, a preservative made infamous by food writer Michael Pollen, is a metabolite of BHA that is associated with both tumor promotion and reduction.

** The knock on vitamin E as a preservative is that products with it have shorter shelf lives.

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