Common knowledge says that humans have the ability to perceive five tastes: sweet, salt, sour, bitter, and umami (protein-richness). But now, researchers have discovered that humans can detect a sixth taste as well: fat. And apparently, people with higher sensitivity to the taste of fat are less likely to eat fatty foods and become overweight.
This sixth taste was the discovery of Dr. Russell Keast and PhD student Jessica Stewart of Australia’s Deakin University, along with collaborators from the University of Adelaide and the Commonwealth Scientific and Industrial Research Organisation in Australia and Massey University in New Zealand. Their research was published in the March 3, 2010, issue of the British Journal of Nutrition.
Dr. Keast’s conclusions are built on American research that found that animals can taste fat. By developing a screening procedure to test for the ability to taste a range of fatty acids found in foods, the researchers found that the capacity among humans to taste fat varies considerably. “Interestingly,” said Dr. Keast, “we also found that those with a high sensitivity to the taste of fat consumed less fatty food and had a lower BMI (body mass index) than those with lower sensitivity.”
It remains to be seen whether an abundance of fat in a diet can desensitize a person’s ability to taste fat, leading to excessive consumption of fatty foods and consequent obesity. Said Dr. Keast, “We are now interested in understanding why some people are sensitive and others are not, which we believe will lead to ways of helping people lower their fat intakes and aid development of new low fat foods and diets.”
Congruent research is being conducted by the National Institute for Deafness and Other Communication Disorders (NIDCD), one of the National Institutes of Health, which is investigating taste disorders and abilities. Differences in the ability to taste may be caused by infections, chemotherapy and other chemical exposures, radiation therapy, head injury, surgery, aging, and smell disorders. Genetic variations have already been shown to influence a desire for sweets. The NIDCD scientists are investigating whether they can harness the unique qualities of taste and smell sensory cells to treat disorders and correct deficiencies.