>> Frank: THIS IS A STORY ABOUT PITS.
NO, NOT THE BARBECUE KIND.
THERE ARE NO CONSTRUCTION PITS EITHER.
AND IT'S NOT EVEN ABOUT THE PITS IN FRUIT.
YEAH, WE'RE TALKING THOSE PITS.
>> IT IS GROSS TO THINK ABOUT THEM, BECAUSE WHEN THEY SMELL,
IT'S REALLY BAD.
>> I DON'T THINK ABOUT IT, BUT I KNOW THE LADIES DO.
SO I GOT TO STAY FRESH FOR THEM.
>> Frank: THAT'S RIGHT.
ARMPITS.
BECAUSE THE REALITY IS, COLD DAY OR HOT DAY,
YOUR ARMPIT IS A WARM, DAMP PLACE.
AND IF YOU'RE A BACTERIA, THAT'S A HAPPY PLACE.
ACTUALLY, WHEN TALKING ABOUT ARMPITS, IT'S NOT THE PERSON
THAT HAS THE ODOR.
IT'S THE BACTERIA LIVING ON THE PERSON THAT PRODUCES THE ODOR.
THE BACTERIA METABOLIZE THE SWEAT AND, WELL, GIVE
OFF THE SMELL.
>> THINK ABOUT IT, NORTH CAROLINA SUMMERTIMES,
YOU KNOW, YOU'RE HOT AND EVERYTHING'S GOING ON.
SO IT WOULDN'T SURPRISE ME AT ALL.
>> Frank: HOWEVER, WEARING ANTI-PERSPIRANTS AND DEODORANTS
DOESN'T JUST AFFECT YOUR SOCIAL LIFE.
IT SIGNIFICANTLY CHANGES THE TYPE AND QUANTITY OF MICROBIAL
LIFE THAT LIVES ON YOU.
MORE SPECIFICALLY, THE CHEMICALS ALTER THE MICROBIOME OF THE
HUMAN ARMPIT.
>> SO SOME OF OUR RESEARCH STUDIES STARTED LOOKING AT HOW
DOES YOUR USE OF ANTI-PERSPIRANT OR DEODORANT OR MAYBE NO
PRODUCT, HOW DOES THAT INFLUENCE WHICH MICROBES LIVE
ON YOUR SKIN.
>> Frank: BUT TO UNDERSTAND WHAT'S LIVING IN YOUR ARMPITS,
YOU FIRST NEED A REFRESHER OF WHAT UNDERARM HYGIENE
PRODUCTS DO.
TAKE DEODORANTS.
>> DEODORANTS CONTAIN THINGS THAT TYPICALLY KILL OFF
MICROORGANISMS, SO THINGS LIKE ETHANOL OR OTHER ANTIMICROBIAL
AGENTS TO KILL THE MICROBES.
AND SOMETIMES THEY ALSO CONTAIN FRAGRANCE OR OTHER PRODUCTS
THAT HAVE A GOOD ODOR.
>> Frank: AND ANTI-PERSPIRANTS.
>> ANTI-PERSPIRANTS CONTAIN ALUMINUM-BASED SALTS.
AND THE ALUMINUM-BASED SALTS WILL GET INTO YOUR APOCRINE
GLANDS, THESE SWEAT GLANDS THAT PRODUCE SWEAT.
AND THEY WILL BLOCK THOSE UP SO THAT YOU'RE NOT PRODUCING
AS MUCH SWEAT.
SO IF YOU DON'T PRODUCE SWEAT, THERE'S NO FOOD
FOR THE MICROBES.
SO, THEN, THERE ARE NO MICROBES THERE, PRESUMABLY.
>> AND WE ASK THEM TO SAMPLE THEIR ARMPIT.
AND SO THEY EITHER WORE A SLEEVELESS SHIRT OR TUCKED AWAY
TO HAVE SOME PRIVACY, AND THEY, EH, EH, EH, EH, YOU KNOW,
SAMPLED THEIR ARMPITS.
>> Frank: RESEARCHERS TOOK DAILY ARMPIT SWABS FROM 17 MEN
AND WOMEN OVER THE COURSE OF EIGHT DAYS.
>> BASICALLY, WE HAVE THEIR BACTERIAL CELLS ON HERE.
>> Frank: SOME PARTICIPANTS USED DEODORANTS.
SOME USED ANTI-PERSPIRANTS.
SOME USED NO PRODUCT AT ALL.
THE STUDY SUBJECTS THEN FOLLOWED THEIR NORMAL HYGIENE ROUTINE ON
DAY ONE, QUIT USING ALL PRODUCTS ON DAYS TWO THROUGH SIX,
THEN ONLY USED ANTI-PERSPIRANTS ON DAYS SEVEN AND EIGHT.
>> BACTERIA, YOU KNOW, WE CAN'T SEE THEM ON THE SWAB.
WE CAN'T SEE THEM ON YOUR SKIN, BECAUSE THEY'RE
INDIVIDUAL CELLS.
>> Frank: RESEARCHERS THEN CULTURED ALL OF THE SAMPLES TO
DETERMINE THE MICROBES GROWING ON EACH PARTICIPANT AND HOW THEY
CHANGED EACH DAY.
THE NUMBER OF MICROBES VARIED WIDELY IN THE FIRST DAYS
OF THE STUDY.
BY DAY SIX, THE AMOUNT OF BACTERIA FOR ALL PARTICIPANTS
WAS ABOUT THE SAME.
>> BUT WHAT WE DO HERE IS, BY GIVING THEM THIS ARTIFICIAL
FOOD SOURCE AND LETTING THEM GROW, WE'RE LETTING EACH
PARTICULAR SPECIES, ALL THOSE CELLS MULTIPLY, TO BE BIG
ENOUGH, WE CALL THEM COLONIES, THAT WE CAN SEE THEM AND OBSERVE
WHO'S THERE.
>> Frank: AND RESEARCHERS FOUND DRAMATIC CHANGES IN MICROBIAL
ORGANISMS BETWEEN DAY SIX, PARTICIPANTS' LAST DAY OF NOT
USING ANY PRODUCT, AND DAY SEVEN AND EIGHT, WHEN SUBJECTS BEGAN
USING ANTI-PERSPIRANTS.
WITHOUT PRODUCTS, MICROBES THRIVED IN THE ARMPIT
MICROBIOME.
>> ONCE YOU STOP WEARING PRODUCT, YOU SORT OF HAVE
THIS CLEAN SLATE NOW.
AND THE MICROBES THAT GROW BACK THE FASTEST ARE THE TYPES
OF STAPH BACTERIA.
>> Frank: BUT ONCE PRODUCTS WERE APPLIED, THERE WERE VERY FEW
MICROBES FOUND IN THE SAMPLES.
IT WAS PROOF HOW PRODUCTS DRAMATICALLY CHANGE THE ARMPIT
MICROBIOME ENVIRONMENT.
>> YOU CAN JUST IMAGINE, THIS IS LIKE YOU JUST HAD A
FIELD, AND A FIRE JUST WENT THROUGH AND WIPED OUT ALL LIFE
THERE, RIGHT?
SO WHEN YOU WEAR DEODORANT OR ANTI-PERSPIRANT, YOU'RE PROBABLY
WIPING OUT MOST OF THE LIFE ON YOUR -- ON YOUR SKIN.
AND SO THEN WHAT GROWS BACK FIRST?
WELL, IT'S THE WEEDS IN THE FIELD, BUT IT'S THE STAPH
ON HUMANS.
SO THAT'S SOME OF WHAT WE'RE LOOKING AT, ALTHOUGH WE DO SEE
SOME OF THE CORYNEBACTERIA GROWING BACK.
THOSE ARE SLOWER GROWERS, TYPICALLY, BUT SOME OF THOSE
DO COME BACK AS WELL.
>> Frank: RESEARCHERS ALSO DID GENETIC SEQUENCING ON THE
SAMPLES TO IDENTIFY THE SPECIFIC BACTERIA AND DETERMINE HOW
VARIOUS PRODUCTS AFFECT MICROBIAL DIVERSITY OVER TIME.
>> EACH SEQUENCE HAS BEEN GENERATED FROM A
DIFFERENT SAMPLE.
>> Frank: THE SAMPLES TURNED UP A GREATER DIVERSITY OF MICROBES
IN THE ARMPITS OF PEOPLE WHO WORE ANTI-PERSPIRANTS.
THAT MIGHT SURPRISE YOU, BECAUSE THE PRODUCTS ARE
DESIGNED TO BLOCK SWEAT GLANDS, BUT --
>> YOU'RE INTRODUCING, YOU KNOW, A VERY DIFFERENT ENVIRONMENT,
RIGHT, BY -- YOU'RE SELECTING FOR POTENTIALLY DIFFERENT
BACTERIA TO GROW.
>> Frank: BOTH TESTS CONFIRM THAT USING ANTI-PERSPIRANTS
AND DEODORANTS COMPLETELY REARRANGE THE MICROBIAL
ENVIRONMENT ON YOUR SKIN, INCLUDING WHAT'S LIVING ON US
AND IN WHAT AMOUNTS.
>> YOU MIGHT SMELL A LITTLE FUNKY THE NEXT DAY, OR OTHER
DAYS YOU MIGHT BE, UH, I DON'T SMELL TOO BAD.
>> Frank: UNTIL NOW, NOBODY KNEW WHAT MICROBES WERE THERE OR HOW
DAILY HABITS CHANGED IT.
>> AND A LOT OF PEOPLE DON'T THINK ABOUT IT.
AND I THINK OUR RESEARCH ISN'T REALLY TELLING US ALL THE
ANSWERS AS TO WHETHER THIS IS GOOD OR BAD, BUT IT'S GETTING
PEOPLE TO REALIZE, I NEVER THOUGHT ABOUT WHAT THIS MIGHT
DO TO MY SKIN AND THE MICROBES ON MY SKIN.