Is Vegemite Banned in the United States?

And what’s in it, anyway?

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Australians living in the United States are spooked because of rumors of a ban on Vegemite. Recent media reports from Down Under have claimed that U.S. customs officials have started searching for the spread. The U.S. government denies that the Aussie delicacy will be banned. What’s in Vegemite, anyway?

A lot of yeast. Vegemite is a brown, salty paste made of leftover brewers’ yeast mixed with vegetables and spices. Australians and New Zealanders often spread it on toast with butter. The taste is strong and bitter, so the spread, which has a consistency similar to margarine, is used very lightly.

The rumors about a possible Vegemite ban stem from the spread’s high concentration of folate, a water-soluble B vitamin. Folate is a vital nutrient that, among other things, helps form red blood cells and prevents neural tube defects in fetuses. Artificial folate, also known as folic acid, is highly regulated by the Food and Drug Administration, though, and only approved for use in a few foods (such as breakfast cereals). But since Vegemite’s folate is naturally occurring—brewers’ yeast contains several B vitamins—it is not banned in America. (Nutritionists typically use “folate” when referring to the naturally occurring vitamin and “folic acid” for the synthetic version.)

The FDA has approved adding folic acid to select foods as a way to ensure that consumers, particularly pregnant women, get enough of the vitamin. If artificial folate were more prevalent, though, it’s possible that people could ingest too much. The recommended daily allowance of folic acid from synthetic foods is 0.4 milligram per dayfor people older than 19. (For comparison’s sake, a “single serving” of Vegemite has 0.1 milligram of folate.) The “tolerable upper limit,” or the maximum amount of folic acid a person should eat in a day, is 1 milligram.

Why is the FDA wary of folate? Because little research has been done into the consequences of ingesting large quantities of the stuff. Nutritionists say that the biggest concern is that excessive folate consumption could mask a dangerous vitamin B-12 deficiency, particularly in the elderly. A 2005 study suggested that elderly people who ingested high amounts of folic acid or folate saw their mental capabilities decline more rapidly than seniors who did not take folate or folic acid supplements.

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Explainer thanks Steven R. Davis of the University of Connecticut and Barry Shane of the University of California, Berkeley.