Body Odor

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History of Body Odor: The human body is heavily scented and is constantly reminding us of our link with the natural world. In Europe in the fourteenth and fifteenth centuries many different perfumes, scented herbs, pot pourri of dried flower petals, and fragrant woods were spread, crushed, daubed, burned, and sprinkled in a hopeless attempt to rid the plague from the air and our bodies (Stoddart, 1990). People were terrified of the plague during this time and believed that every breath they took would infect them unless the breath had a bit of sweetness or nice scent to it. Then, they felt, the scent would kill the plague (Stoddart, 1990). For many centuries doctors would wear long leather coats covered in honey-scented beeswax in order to protect them from disease (The Scented Ape). English judges would carry sweet- smelling herbs with them when they visited prisoners in jail in an attempt to fight off jail fever, which is now known as typhus (Stoddart, 1990).

Social Status: Throughout history, body odor has been associated with low social status. During the last decade of the middle ages, only wealthy people, such as landlords, had access to baths because they had the means to hire servants to fill up and heat their baths, a labor-intensive chore. Most other people never bathed and wore the same set of clothes for months on end (Stoddart, 1990). However, during the seventeenth century, when Louis XIII and Louis XIV were in power, cleanliness became a matter of appearance. White powder was rubbed into collars, cuffs, and bands, and wigs were powdered to cover up their smell. Rather than washing clothes, a lot of perfume was worn in order to cover up the stench caused by natural body odor (Stoddart, 1990). So, throughout history, scents were used, first, in order to fight off disease, and then, in order to depict social status as well as enhance appearance.

Function of Body Odor: Body Odor serves many functions in our lives. Our body odor influences our mating preference, the relationships we form, and who we’re attracted to. Our mating preference and our odor are both driven by sexual selection and are influenced by highly polymorphic genes of the major histocompatibility complex polymorphisms (MHC) (Barrett, 2007). Studies have found that both males and females prefer MHC-dissimilar mates, whom they recognize by odor cues (Barrett, 2007). Humans also have a functional vomernasal organ, which is a chemical sensory system in mammals that is used to detect pheromones. This vomernasal organ influences women’s reproductive synchrony (Barrett, 2007). Body odor acts as a biological signal in two ways: individual recognition and indication of current state (Roberts, 2011). 1. Individual recognition: studies have shown similarities in body odor among twins and other relatives, suggesting that body odor has a genetic basis. People are able to recognize their own body odor, the body odor of their partner, and the body odor of their relatives. Mothers and infants recognize each other’s body odors right away and are able to identify them throughout life. This may play a significant role in mother-infant attachment. Odor preference away from the family and towards non-family members develops during puberty and has been suggested to cause incest avoidance. 2. Indication of current state: -Reproductive state: Women’s scent is the most potent during ovulation. -Diet: Mice who were starved for twenty-four hours were unattractive to other mice. However, after these mice were fed, other mice began to find them attractive. -Health status: Those with diabetes tend to have a smell of acetone on their breath; infectious agents cause changes in body odor. -Affective state: Body odor changes, depending on emotional state whether it be anger, anxiety, frustration, or fright. Even though body odor is meant to serve all of these different signaling functions in our lives, we have developed so much away from this signaling that our olfactory abilities have largely been lost (Roberts, 2011). However, people are still concerned about the way they smell. In Western culture, almost everyone can afford to use some kind of product to cover up their body odor, and most do, even though they shower often. In a poll taken, 79 % of women and 60% of men use deodorant every day and only 4% of women and 8% of men said they never use deodorant; 44% of women use perfume every day (Roberts, 2011). Studies have shown that men and women find themselves more attractive when they’re wearing deodorant or perfume, giving them more confidence and making them more attractive to others (Roberts, 2011).

Causes of Body Odor: Body odor, or B.O., or Brohidrosis typically becomes noticeable once a person hits puberty, usually 14-16 years of age in women and 15-17 in men. Body odor is often blamed on our sweat, but our sweat is not actually the direct cause of the odor. The odor itself actually results from the metabolizing of bacteria on the skin of different areas of the body. The bacterium breaks down the sweat into acids that cause the smell. We have two types of sweat glands, eccrine and apocrine glands. Sweat from eccrine glands is mostly made up of water and salt and is secreted to cool the body off when you overheat. Our apocrine glands are located in hair follicles, and produce a sweat containing proteins and fatty acids. A carbohydrate called sialomucin, which has an outer coating of sugar, is found in this sweat. This simple sugar coating is a prime target for bacteria to break down as a source of energy through fermentation or aerobic or anaerobic respiration. As the bacteria, unique to whichever body part on which they reside, break down the sugars, they reproduce rapidly and release the acids that produce the odor. So, no matter how healthy your skin is or how clean you are, your body is still home to thousands of different strains of bacteria that go through these processes and produce some kind of odor. Some suggest that the reason we perceive body odors negatively is because we have been conditioned socially to do so. Some odors produced by the processes aforementioned are inoffensive to us, and are unique to the individual, which is what allows certain animals, like dogs, to be able to identify humans individually.

What Makes You Smell: Things like food, age, gender, medications, etc. can affect each person’s individual odor. For example, some studies show that people who tend to eat red meat are more likely to have noticeable body odor than vegetarians. Also, eating spicy foods increased body temperature, causing the sweat glands to produce sweat and therefore may cause odor. Body odor is most likely to occur on the feet, groin, genitals, armpits, belly button, and near body hair. It does occur in other areas of the skin, but it’s likely to be less noticeable or intense in these areas. The acids that are produced in these areas, the culprits for producing the smells, are commonly Propionic or Isovaleric acids. Propionic acid is found in sweat, and is processed by a type of bacteria found on sebaceous glands called Propionibacteria. Isovaleric acid is commonly found on feet, processed by the bacteria Staphylococcus epidermidis, which as we have learned is also found on some types of cheese. We typically think of feet being one of the main sources of odor on the body. Feet tend to smell because when people choose to wear shoes and socks, the perspiration cannot evaporate, and is contained within the sock. This gives the bacteria living on the feet more time and sweat to metabolize, and more time to multiply. Too much moisture on the feet also runs the risk of growing fungus, which may also contribute to the odor.

The Genetics of Body Odor: Bromhidrosis is inherited genetically, and it is an autosomal dominant trait which means that if either one of the chromosomes carries the disease the person will have symptoms. If a person has the bromhidrosis gene, the amount that they sweat affects the amount of fat molecules secreted, which come from the apocrine glands. Since bacteria use the sweat from the apocrine glands as nutrients to grow, this causes a strong body odor. Without the bromhidrosis gene, no matter how much a person sweats they will not exhibit any bromhidrosis symptoms. Genetics of bromhidrosis. This is a scenario of possible offspring if one parent has a gene for bromhidrosis.

 http://neogenelab.com/cd_news.aspx?c=9 

East Asians are much less susceptible to excessive sweating and body odor because they have fewer apocrine sweat glands compared to people of other descents. This reduction in body odor and sweating is due to their adaptation to colder climates. One condition that may contribute to bromhidrosis is hyperhidrosis. Hyperhidrosis is a genetic medical condition where the eccrine sweat glands are overactive, so a person sweats excessively and even when temperatures are cold, or when they are resting. This unpredictable sweating can lead to major discomfort physically and emotionally. Further studies must be done on this condition to prove whether hyperhidrosis encourages a more severe case of bromhidrosis or if it actually helps to prevent it. Some researchers suspect that the excessive eccrine sweat glands trigger the apocrine sweat glands to also become overactive, while some researchers suspect that the odorless sweat from eccrine glands can help wash out the smelly sweat from the apocrine glands. This condition affects 2-3% of the population, and can be inherited as an autosomal dominant genetic trait.

Another cause of body odor is trimethylaminuria (TMAU). TMAU is a genetic disorder causing a smelly fish body odor. This condition is caused by an inability to properly metabolize trimethylamine (TMA), allowing it to build up in their body. The buildup in trimethylamine exudes a fishy stench through the person’s breath, saliva, sweat, and urine. Most commonly this condition comes from a mutation in a person’s FMO3 gene. This gene provides the instruction to make an enzyme that breaks down trimethylamine. Trimethylamine is produced by bacteria in the intestine when they help to digest proteins from several sources such as liver, most seafood, soybeans, eggs, and some others. This is a recessive trait, so there must be a mutation in both copies of the FMO3 gene to result in a severe case of TMAU. However, a mutated FMO3 in just one copy of the gene can cause a reduced amount of this enzyme to be produced, causing trimethylamine to slightly build up in the body which creates a mild case or temporary episodes of TMAU. Without the mutation to FMO3, the enzyme is able to convert fishy-smelling trimethylamine into a different molecule that has no odor. Genetics of TMAU. This picture depicts a scenario of possible offspring if both parents are carriers of TMAU. http://www.absoluteastronomy.com/topics/Trimethylaminuria Another cause of TMAU comes from a compound known as indole-3-carbinol. This compound blocks the function of the enzyme system that breaks down trimethylamine. It is found in broccoli, leafy greens and other green vegetables. TMAU can be treated through changes to the diet or with antibiotics. Without eating food that contains indole-3-carbinol, or any foods that are digested by the bacteria that create trimethylamine, there will be no build-up of it in the body and therefore no odor will be emitted. Antibiotics can also be taken to combat the bacteria in the gut that are producing trimethylamine. One last way this genetic disorder can be treated is to use soap with a pH between 5.5 and 6.5, which is lower than common brands of soap. Since trimethylamine is a strong base with a pH of 9.8, soaps that have a pH similar to skin (which is about 5.5), can help retain the secreted trimethylamine in a form that can be removed by washing. An estimated 1 to 11 percent of the population has this disorder.

Treatments and Drugs for Body Odor: Deodorants and Antiperspirants There are two drugs that are commonly used to help fight body odor but they differ in one specific detail that one helps prevent sweating while the other just attempts to help eliminate the bad odor when we do sweat. The first drug is something called an antiperspirant that contains aluminum-based compounds that temporarily block the sweat pore, thereby reducing the amount of perspiration that reaches your skin. Therefore, this drug stops people from sweating. The other over-the-counter drug that can help with body odor is a product called deodorant. Deodorants can eliminate or neutralize odor but not perspiration. They are usually alcohol-based and turn your skin acidic, making it less attractive to bacteria. Deodorants often contain perfume fragrances that are intended to mask the odor of perspiration and are used on the hands and feet as well as the underarms.

If the over-the-counter antiperspirants don’t help control your sweating, your doctor may prescribe aluminum chloride which can be found in products called Drysol and Xerac Ac. These are stronger antiperspirants and they try harder to prohibit excess sweating than the over-the counter choices. Doctors also suggest, for the best results, to apply the antiperspirant at night to the areas most prone to sweating which is most commonly the underarm area. These stronger prescriptions do have some side effects that include red, swollen, and itchy skin much like a rash.

Organic Options There are ways to neutralize your body odor without man-made chemicals. The move towards more organic solutions has also made its way into the world of health and beauty. Most department stores and grocery stores now have organic deodorant available for a more expensive price than their man-made counterparts. Other less expensive ways to help neutralize odor can be by simply changing your diet. Eating less junk foods or highly processed meats can help you smell less. Eliminating other pungent foods like garlic or onion that will create an equally pungent smell from your diet will also help your sweat smell less. Other foods that can supplement your diet that will also help neutralize body odor. Apple Cider vinegar has cleansings properties which can help eliminate body odor despite its own strong aroma. Drinking about one tablespoon two or three times a day is enough to cleanse most bodies. Tea is also used to cleanse the body, eliminates odor, is delicious, and provides many health benefits. Drinking a cup of sage tea can help reduce body odor.

The most potent purifying tea of all is called Kombucha which is a fermented Chinese tea with an abundance of probiotics and “system purifiers.” Kombucha is a living health drink made by fermenting tea and sugar with a Kombucha culture. The result can taste like something between sparkling apple cider and champagne, depending on what tea is used. Kombucha culture looks like a beige or white rubbery pancake and is often called “scoby” which “stands for symbiotic culture of bacteria and yeast.” The culture is placed in sweetened black or green team and turns a bowl full of sweet tea into a bowl full of vitamins, minerals, enzymes and health-giving organic acids. It is thought to have originated in the Far East, specifically China, and has been consumed for at least two thousand years. The first recorded use of Kombucha comes from China in 221 BC during the Tsin Dynasty and is known as “The Tea of Immortality.”

Compiled by Gen Barlow, Ellie Moore, Melissa DellaTorre, and Casey Correa

Kombucha

 http://www.alternativeconsumer.com/2008/12/11/cost-effective-kombucha-in-5-steps/

Applying baking soda to the armpit or feet will also help neutralize odor. It is inexpensive and can be conveniently found in most pantries. It is also recommended that instead of taking a shower you in fact take a bath with a couple drops of rose water. It is relaxing and soaking in the essential oil will create a longer-lasting neutralization of body odor than baking soda.

References:

Barrett, L. (2007). The oxford handbook of evolutionary psychology. New York,NY: Oxford University Press.

Courtade, Brandy. (2012). Natural Remedies for Fighting Body Odor Internally and Externally. Retrieved from http://www.dailyglow.com/natural-remedies-for- fighting-body-odor-internally-and-externally.html

Hugat, J. L. (2011, September 02). Unexplained body odor may stem from rare genetic disorder. Retrieved from http://www.washingtonpost.com/blogs/the-checkup/post/unexplained-body-odor-may-stem-from-rare-genetic-disorder/2010/12/20/gIQAh4MMvJ_blog.html

Manning, N. (2012). What is TMAU?. Retrieved from http://tmau.org.uk/index.php/79- tmau-frontpage-cat/73-what-is-tmau

Mayo Clinic Staff. (2011, August 2). Treatments and Drugs. Retrieved from http://www.mayoclinic.com/health/sweating-and-body-odor/ds00305/dsection=treatments-and-drugs

Neo Gene Lab. (2012). Gene test and Research Center: Bromhidrosis in General. Retrieved from http://neogenelab.com/cd_news.aspx?c=8

Nordqvist, C. (n.d.). What Is Body Odor (B.O.)? What Causes Body Odor?. Medical News Today: Health News. Retrieved May 8, 2012, from http://www.medicalnewstoday.com/artic

Roberts, C. (2011). Applied evolutionary psychology. Oxford Scholarship Online. Retrieved from http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780199586073.001.0001/acprof-9780199586073-chapter-0020

Stoddart, D. M. (1990). The scented ape: The biology and culture of human odour. New York, NY: The Press Syndicate of the University of Cambridge.

Wingfield, R. (2012, January 17). Bromhidrosis. Retrieved from http://emedicine.medscape.com/article/1072342-overview#showall