In a quest to find out why we favor brownies over berries or Brie over broccoli, we have been more or less tongue-tied. While the smell of a simmering stew can prime the appetite to signal the brain, "something smells yummy enough to eat," the sensors in the nose and back of the throat are not the whole story. It is only when smell joins up with taste perception that the full flavor experience is unleashed.
Researchers have been wondering if our sense of taste influences food choices that ultimately effect body weight. Some studies found that women "super-tasters" ate less overall, had lower BMIs and were 20 percent thinner than non-tasters. And people who have a history of recurrent ear infections, which damages your taste nerve, tend to be overweight.
Could the amount of the mushroom-shaped buds that pepper the surface of the tongue offer clues to why discerning diners and feeble foodies differ when it comes to weight?
The Power of Taste
How we taste is important because taste, not smell, gives you the nutritional information of foods. Carbohydrates and sugars are sweet; minerals are salty and bitter; and proteins, fats and vitamins have no taste (except for Vitamin C). Umami, however, a proposed, yet contentious new taste type, corresponds to a taste for glutamate, a chemical that is derived from the breakdown of proteins. Umami might explain why steaks aged for a long time are tastier than lesser-aged ones.
In general we tend to prefer sweet and salty to sour and bitter, a note that sends a signal to the brain that a food may contain acids or toxins.
The Bitter Truth
Taste sensitivity depends on the number of taste receptors on taste buds and the number of taste buds on the tongue. To measure this, scientists use a wafer that contains a drop of a chemical called 6-n-propylthiouracil, or PROP, which has a nasty bitter taste. Placing this on the human tongue can send a super-taster through the roof, while non-tasters just taste the paper.
Statistically, most people fall in the middle, while 25% are non-tasters and 25% super-tasters. You won't be able to get PROP without a prescription but you can do a non-scientific experiment at home using blue food coloring. Since taste buds won't stain you can see the bumps; 30 dots or more means you are a super-taster, less then 5, an under-taster.