Armpit Odor in Children

Armpit odor is a common occurrence, with wide ranges of severity. As children age, hormonal changes related to puberty induce the production of novel sweat glands, which commonly leads to body odor. The connection between the types of sweat glands and the degree of body odor lies in the bacteria present on our skin. Many factors come into play regarding armpit odor severity including amount of sweating, species of bacteria present, and even genetics of the individual. The etiology of armpit odor may be a combination of several of these factors.

Causes of Armpit Odor

Body odor does not directly come from sweat or secretions produced by your body; this is a common misconception regarding its origin. In fact, the source lies within fat molecules, known as lipoproteins, some of which are located on the surface of your skin. It is widely accepted by the medical community that armpit odor is caused by microbial biotransformation of these odorless lipoproteins into highly volatile, odorous compounds. It's not the sweat that smells; it's the chemicals produced by bacteria from components of your sweat. The chemicals produced include ammonia and short chain fatty acids, which are characteristically malodorous.

Mechanism of Odor Production

The armpit, also known as the axilla, is the home to four principal groups of bacteria, with staphylococcal or aerobic coryneform species acting as the dominant strain. There is a particularly strong association between the presence of Corynebacterium species and body odor. It can be concluded that these bacteria are the primary types responsible for converting sweat products into ammonia and fatty acids.

Impact of Puberty

The primary reason young children do not typically produce body odor is because their sweat glands are strictly of the "Eccrine" type. Eccrine glands are located over the entire surface of your skin, where they can properly serve their function as thermoregulators by producing sweat. As the child progresses to puberty, the populations of glands within the axilla, the genital area, as well as on the feet, begin switching to the "Apocrine" type. Apocrine glands are primarily responsible for producing an oily, phermonal fluid; these glands do not take part in thermoregulation. Apocrine glands are under control of the sympathetic nervous system; over activation of sweat glands, known as hyperhidrosis, often leads to body odor. A moist, warm environment allows the resident bacteria to thrive, increasing the intensity of the odor as the population rises.

Expert Insight

While the species type and population density of bacteria play a large role in producing armpit odor, research shows that genetics also contribute substantially. According to an article published in 2010 for the Journal of Investigative Dermatology, the gene ABCC11, which encodes a transport protein in the skin, is crucial for the biochemical formation of axillary odor. The researchers claim that absence of this transporter prevents the movement of lipoproteins to the skin's surface, thus depriving resident bacteria of this food source. It has been shown that Asians, who do not typically have strong armpit odor, possess a loss of function mutation in ABCC11. Similarly, Caucasians and Africans, who more commonly possess a strong axillary odor, possess a properly functioning gene. This research points to a strong genetic basis for axillary odor production.

Solution

There are several general approaches to dealing with excess body odor which are minimally invasive and therefore optimal for children. Changes in diet might be considered, as certain foods and spices are secreted in our sweat and remain in these excretions for several hours. Diets rich in cumin, fish, garlic and curry commonly produce body odor through this mechanism. If the child or adolescent has excess underarm sweat production, a physician may need to determine the cause of the excess sweating, which might include generalized anxiety or a correctable metabolic condition. The root issue can be addressed, consequently relieving the patient of the symptom of excess sweating and armpit odor.