Body Odor

Alternative names: BO, B.O., Bromhidrosis, Bromidrosis

Conventional wisdom suggests that perspiration (sweat) is the cause of body odor.  However, perspiration by itself is basically odorless: body odor is in fact caused by bacteria on our skin breaking down the sweat and producing smelly waste products.

The armpits are an ideal place for bacteria to thrive: they are moist, warm, usually dark, and well supplied with tasty body secretions.  If no countermeasures are taken, the bacteria will multiply quickly.

Some of us appear unable to notice our own body odor due to a phenomenon called 'olfactory fatigue'

Thousands of different types of bacteria can potentially inhabit human skin and (in particular) the armpits, but only a few are responsible for body odor.

The other places where bacteria can produce odors are the feet, groin (genitals, pubic hair), other hair, belly button, anus, behind the ears, as well as the rest of our skin to a lesser degree.

Body odor is unique to each person, which is why dogs and other animals can use it to identify people.  In some cases it can even be pleasant.  Many factors can influence a person's body odor, for example their gender, diet, overall health, and medications being used.

Incidence; Causes and Development; Contributing Risk Factors

Body odor usually becomes noticeable once we reach puberty.

The average human has between 2 and 5 million sweat glands on their body.  These glands come in two varieties.  Eccrine glands are found all over the body and help cool the body when the sweat they produce evaporates.

Apocrine glands are glands that produce odorless oily secretions that develop their characteristic smells when broken down by bacteria.  They are found in the armpits, genital area, breasts, eyelids, nostrils, perianal region, and ears.  In the breasts they secrete fat droplets into breastmilk, and in the ears they help form earwax.

Researchers at the University of York reported in 2015 that when bacteria break down these odorless compounds, they produce chemicals called thioalcohols.  These waste products are often very pungent and smell similar to sulfur, onions, or meat.  These compounds then evaporate from the armpits and become a smelly nuisance.

Another potential cause of body odor is the foods, chemicals, and medicines that we ingest.  Examples of odor-causing foods include garlic, onions, and curry spices: when broken down by the body, these produce sulfur-containing waste gases that escape through the pores in our skin.  Any imbalances in metabolism can result in stronger odors.  Note however that in 2015 it was found that garlic may actually improve body odor because of its antibacterial properties.

When a person drinks more alcohol than their liver can break down, some of it is excreted through their breath and sweat.

Smelly waste products can also be the result of toxins that accumulate in our bodies.  In today's world we are bombarded with toxins in our homes, food, and air that accumulate in the body when the organs of elimination cannot dispose of them.  The liver, kidneys, and intestines may be 'clogged up', causing odors to escape through the skin.  In this case, a thorough detoxification program that cleanses the liver, kidneys and colon may be useful.

Dietary imbalances – resulting in constipation or a deficiency of magnesium or zinc – can also be causes of body odor.  Because of different body chemistries, some people have a very distinctive body odor which can be quite offensive.  Some individuals cannot metabolize foods containing large amounts of choline, such as eggs, fish, liver and legumes.  The result is a 'fishy' smell.  If you are one of these people, cut out these products and see if this is the cause of your odor.

Some other possible cause of body odor:

• Kidney disease
• Liver disease
• Fungal infections
• Refined sugar (feeds bacteria and fungus on the skin)

Being overweight, eating certain foods, and certain medical conditions such as diabetes or hyperhidrosis (sweating too much) can increase the likelihood of having body odor.

Stress also plays a role in body odor.  When we are stressed, the apocrine glands produce "stress sweat" which contains a milky fluid consisting of proteins, carbohydrates and lipids.  This causes the smelliest types of body odor when broken down by bacteria.  In contrast, when we exercise, our eccrine glands produce sweat contains mainly water and electrolytes (salt), which does not cause such odor problems.

Treatment and Prevention

Treating body odor is more a case of prevention rather than cure.

It goes without saying that wearing clothes several times between washing will lead to an accumulation of oils, bacteria, and odors, so change clothes frequently.  The same goes for bras: don't wear the same bra two days in a row.  Avoid synthetic fabrics such as spandex, which trap sweat and cause odors to linger.  Breathable fabrics such as cotton, sheer mesh, or lightweight lace are able to wick away moisture more easily.

Shower at least once a day to remove sweat and bacteria, using 'antibacterial' soap if preferred.  After washing, dry yourself completely – especially in the areas susceptible to body odor.

Wear socks with closed shoes, and change socks regularly.  Without socks to absorb the moisture, the feet are essentially bathing in their own sweat and bacteria.  Remember also that antiperspirant can be applied to the feet if necessary, and deodorant powder is available for use in shoes.  If possible, take shoes off every once in a while during the day, and give shoes time to air out by not wearing the same pair for two days in a row.

Use a deodorant or antiperspirant.  Deodorants have a scent that masks the smell, whereas antiperspirants reduce sweating and often include a deodorant as well.  Higher strength and prescription antiperspirants are available if necessary.  Note that most commercial antiperspirants and deodorants function by blocking sweat glands (which can lead to irritation and swelling) and/or killing underarm bacteria (which can also kill good bacteria.)

Natural solutions

Salt crystal deodorants do not contain parabens or aluminum compounds, which may contribute to increased breast cancer risk

• For those who are concerned about potentially hazardous ingredients in modern-day products (such as aluminum chloride in antiperspirants), salt crystal deodorants are a natural alternative, made from only crystallized mineral salts.  Simply moisten the area to be covered, and wipe the salt crystal across it several times.  This will leave a thin salt film on the skin: salt kills bacteria by drying them out and stopping the chemical reactions that they need in order to live and reproduce.
• Reduce intake of spicy foods, caffeine, and alcohol which increase perspiration
• Reduce intake of garlic, onions and other foods that produce pungent gasses when broken down inside the body
• Wipe your armpits with alcohol, white vinegar or witch hazel instead of deodorant
• Apple cider vinegar eliminates underarm odor when used in place of deodorant because it reduces the pH of the skin, making it hard for bacteria to live there
• Use baby powder or talc in areas of heavy perspiration
• Baking soda, the odor-eating standby, can be used instead of deodorant by simply applying the powder to dry armpits.  It will kill bacteria and help absorb perspiration.  Cornstarch can be used instead, or mixed with the baking soda.
• Chewing parsley, alfalfa and other leafy greens will help neutralize body odor, probably because of the deodorizing effect of the chlorophyll
• Juice about two dozen radishes, add ¼ teaspoon of glycerine, and put in a squirt or spray-top bottle.  Use as an underarm deodorant or to reduce foot odor.
• Rosemary is an antibacterial herb.  Put 8 to 10 drops of the essential oil in 1 ounce of water and apply it where needed.
• Sage.  Herbalists suggest drinking a cup of sage tea daily to reduce sweat gland activity.  This is especially true for those who perspire excessively due to tension.  Use 1½ teaspoonsful of dried sage or two tea bags in one cup of water, steep for ten minutes, and drink in small doses throughout the day.  Fresh sage leaves blended with tomato juice has been found to be very effective.
• Tea tree is an antibacterial herb.  Make a deodorant by putting 2 drops of the essential oil into 1 ounce of water and apply where needed.
• Towelettes (baby wipes) are useful when a tense moment causes a surge in stress hormones which produce fluid under the arms and around the genital areas that, when combined with bacteria, causes odor.
• Turnip juice will reduce underarm odor for up to 10 hours.  Grate a turnip and squeeze through cheesecloth to produce two teaspoonsful of juice.  Wash your armpits first, then vigorously rub one teaspoonful under each.
• Take 500mg of wheat grass daily on an empty stomach and wash down with a glass of water.  The chlorophyll will dramatically reduce body odor.
• Some Homeopaths recommend dissolving three 6X tablets of the tissue salt Silicea under the tongue each morning and evening to knock out odor

Seek medical attention if...

Most of us have experienced sweating and body odor when exercising, too warm, or nervous, anxious or under stress.  This is completely normal, and some people naturally sweat more or less than other people.  However, changes in sweating or body odor may be a sign of an underlying medical problem.

For this reason it is important to visit a doctor if you:

• begin to sweat much more or less that normal
• sweat so much that it affects your daily activities
• experience night sweats for no obvious reason
• have a distinct change in body odor.