Human beings were found out having an incredible ability to smell up to one trillion scents. However, it's ironic that they can't even smell themselves.

Time reported the incredible ability of the olfactory sense of human beings though it's the down bottom among the five senses. Aside from the incredible ability of human beings to distinguish several millions of different colors and millions of different sounds, human beings can further sense 10,000 different kinds of odors based on the 1927 study.

Meanwhile, a study has found out how sensitive human beings' noses are. The study was conducted by the Researchers at the Rockefeller University with the combined efforts of Howard Hughes Medical Institute or HHMI.

The researchers have used volunteers to test the sense of smell with the use of the variety of odor molecules mixed together. The results showed that human beings can distinguish between one trillion different kinds of odors making the nose much sensitive than any other organs in the body.

Andreas Keller, a research associate and lead author from the Rockefeller's Laboratory of Neurogenetics and Behavior proved the study as a fact. "The message here is that we have more sensitivity in our sense of smell than for other parts which we give credits. We just don't pay attention to it and we don't use it in everyday life," Keller said.

However, a big question follows such study, "If human beings can smell almost one trillion scents, why they can't smell themselves, even when they stink?" The question seems to be funny but it's a reality, and according to Business Insider, Science has an explanation to solve this curiosity.

The condition is technically known as olfactory fatigue, odor adaptation, olfactory habituation or in layman's term "nose-blind." This might sound as a defect, but can be explained by being too much focused on the smells around the surroundings than smells of their own. Besides, most of the time human beings are not aware that they're smelling anything at all especially their own scents.