Speaker 1: Welcome to brain Stuff production of I Heart Radio. Hey
Speaker 1: brain Stuff, Lauren vogel Bomb here with another classic episode
Speaker 1: from our archives. Lots of athletic wear and outdoors gear
Speaker 1: is labeled with claims that it will help wig away
Speaker 1: sweat and keep you smelling as fresh as if you
Speaker 1: just stepped out of the shower. In this episode, we
Speaker 1: look at how those claims can possibly be true and
Speaker 1: how they can sometimes fall through. Hey there, brain Stuff,
Speaker 1: Lauren vogel bomb here. If you're preparing for a hike,
Speaker 1: especially one that involves sleeping under the stars, every last
Speaker 1: thing you pack should be questioned, will you need rain gear?
Speaker 1: One walking sticker to which freeze dried snacks are actually
Speaker 1: tasty enough to eat. One essential rule from experienced hikers
Speaker 1: is no cotton clothing. Clothes made of cotton can act
Speaker 1: as a sponge. The material soaks up sweat and holds
Speaker 1: moisture next to the skin, which eliminates the insulating effect
Speaker 1: of the cotton, causes skin ear tation and eventually leads
Speaker 1: to copious amounts of body odor. A body odor isn't
Speaker 1: a personal affront. Every adult whose body temperature becomes high
Speaker 1: enough to cause certain glands to secrete fluid onto the
Speaker 1: surface of the skin is at risk for emanating at
Speaker 1: least a little bit, and it isn't without purpose. Sweat
Speaker 1: produced by the acrine glands that cover most of the
Speaker 1: body helps regulate body temperature, while the milki or fluid
Speaker 1: released by the apocrine glands in the armpits and growing
Speaker 1: area is a signal that the body is under stress.
Speaker 1: Apocrene glands are primarily responsible for body odor, and although
Speaker 1: acrine glands secrete primarily odorless sweat, the smell produced by
Speaker 1: this sweat changes over time. Perspiration acts as a magnet
Speaker 1: to bacteria on the skin, and these bacteria use it
Speaker 1: as a fuel to multiply. When the growing numbers of
Speaker 1: bacteria metabolize the sweat, they produce a smelly byproduct commonly
Speaker 1: called body odor. Clearly, cotton isn't the right choice for
Speaker 1: working up a sweat, since it can actually make body
Speaker 1: odor worse. But what about other types of fabrics? Do
Speaker 1: all fabrics increase a person's propensity to develop body odor.
Speaker 1: The key to using clothing to prevent or lessen body
Speaker 1: odor lies in the fabric's ability to release sweat quickly
Speaker 1: before bacteria can begin to feast on it. There are
Speaker 1: natural and manmade fabrics that expertly wick moisture away from
Speaker 1: the skin and to the edge of the material, where
Speaker 1: it can evaporate. Other fabrics, however, will trap moisture in
Speaker 1: the fabric and on the skin and make body odor worse.
Speaker 1: Fabric's ability to transmit and release moisture is known as breathability,
Speaker 1: which is the common term for the moisture vapor transmission rate,
Speaker 1: or m v TR. The m v TR is measured
Speaker 1: by calculating how many grams of moisture move through a
Speaker 1: square meter of fabric in twenty four hours. Generally, the
Speaker 1: greater the m v t R, the less likely the
Speaker 1: fabric is to absorb and retain odor causing moisture. You
Speaker 1: may be thinking, great, now, all I have to do
Speaker 1: is find clothing labeled breathable, and bo will be a
Speaker 1: problem of the past. Not so fast. There's not an
Speaker 1: industry standard regarding breathability. Nearly any label can carry the term,
Speaker 1: usually preceded by words like ultra or extremely. This means
Speaker 1: you'll need to arm yourself with information about specific fabrics,
Speaker 1: rather than relying on label hype as a guide. Natural
Speaker 1: fabrics created from the fibers of animals, bugs, or plants
Speaker 1: are a good place to start. You'll want to steer
Speaker 1: clear of one percent cotton fabrics because they take a
Speaker 1: long time to dry and will allow body odor to
Speaker 1: bloom in the meantime. This is largely because one cotton
Speaker 1: fabrics are composed of fibers that swell with moisture and
Speaker 1: thereby reduce the pores of the fabric. However, other natural
Speaker 1: fabrics absorb and release sweat quickly, including hemp, a fabric
Speaker 1: woven from these stem fibers of the Cannabis sativa plant,
Speaker 1: and linen woven from flax stems. While it sounds counterintuitive
Speaker 1: to wear wool to prevent body odor, this natural fiber
Speaker 1: is an excellent choice. Wool can absorb up to thirty
Speaker 1: six percent of its weight and moisture without feeling wet,
Speaker 1: and will dry quickly. Will also pass minute amounts of
Speaker 1: body heat as it absorbs moisture, so it will help
Speaker 1: keep you cool. Plus, will is naturally antibacterial, which means
Speaker 1: you can wear it, sweat in it, and keep wearing
Speaker 1: it sometimes for consecutive days without reeking. When it comes
Speaker 1: to making body odor worse, synthetic fabrics tend to trap
Speaker 1: odors at a greater rate than natural fabrics. Although many
Speaker 1: of these man made fabrics, like polyester, are quick to
Speaker 1: wick moisture away from the skin and equally quick to dry,
Speaker 1: their construction can up the stink quotient within the weave
Speaker 1: of synthetic moisture. Waking fabrics are notches designed to pool
Speaker 1: minute amounts of sweat as it transfers from the inner
Speaker 1: layer to the outer layer of the fabric. The concept
Speaker 1: is a good one, as the moisture will generally evaporate
Speaker 1: once it reaches the fabrics outer layer. The problem is
Speaker 1: that as sweat collects in the NOx and crannies of
Speaker 1: the fabric on its way to freedom, it is devoured
Speaker 1: by bacteria that have themselves made a home in those
Speaker 1: same recesses. This traps body odor within the fabric. To
Speaker 1: reduce rowdy odors, look for synthetic fabrics that have an
Speaker 1: added a a microbial ingredient. For example, the addition of
Speaker 1: silver to polyester or spandex fibers can help prevent body
Speaker 1: odor from accumulating silver nano particles. That's particles so small
Speaker 1: that eighty thousand of them could fit within the diameter
Speaker 1: of a human hair can be integrated into synthetic fabric.
Speaker 1: When they get wet, the silver nano particles release silver
Speaker 1: ions that initially slow the growth of odor causing bacteria
Speaker 1: and eventually kill them off altogether. Some fabrics are infused
Speaker 1: with a different type of odor inhibiting agent, molecules of
Speaker 1: volcanic ash. The ash molecules have a poor size that's
Speaker 1: similar to that of an odor molecule. When the two meat,
Speaker 1: the odor molecule is adsorbed and trapped within the ash molecule.
Speaker 1: This prevents the odor molecule from releasing its characteristic smell
Speaker 1: until the fabric is washed in warm water. To prevent
Speaker 1: body odor, look for clothing made from fabrics that will
Speaker 1: help keep you dry and have the added mite of
Speaker 1: antimicrobial helpers, and don't forget the antiperspirant or deodorant. Today's
Speaker 1: episode was written by Laurie L. Dove and produced by
Speaker 1: Tristan McNeil and Tyler Clang. For more on this and
Speaker 1: lots of other fresh topics, visit how stuff works dot com.
Speaker 1: Brain Stuff is production of I Heart Radio. Or more
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