They're called "Miracle Fruit Tablets" and they're made from a small red berry called miracle fruit, or Synsepalum dulcificum, native to West Africa. So how does it work? The pulp of the berry contains a protein, called miraculin, that binds to the tongue and blocks the taste bud receptors responsible for sour and bitter flavors for up to an hour. Lemons taste like lemonade, vinegar tastes like apple juice, and strawberries taste like candy.
Miracle berry tablets make for great flavor-tripping parties, but they may also have other benefits. Some health experts says the berries could reduce the dependence of sugar in our diets. And according to a study done at Mount Sinai Medical Center, the fruit may help make food more palatable for cancer patients undergoing chemotherapy.
When the EyeOpener anchors tried the berries, they were pretty impress by how sweet a lemon suddenly became ... but that's about the only food that truly tasted better. The berries are definitely not a magic 'make vegetables taste like candy' pill. Brussels sprouts still tasted very much like Brussels sprouts, and bitter chocolate still had its trademark kick. So to answer the question posed in the headline: no, "miracle" fruit tablets do not make all (or even most) food taste sweet.
The tablets are not yet FDA approved, so you might not want to dash to the store just yet.