Sweating in the sweltering summer heat

It's that time of year when the typical conversation piece is how hot it is. A mother who shares a bed with her four children told me how, at nights, every child is scrambling for his head to be directly under the fan.

Some people refuse to exercise at this time because they do not like to perspire. Eleventh-grade biology, which I swatted 27 years ago, read, 'Man cools himself in various ways: He wears less clothing (loose, light clothing made of breathable, natural fibres like cotton or linen); he consumes cold beverages; he bathes himself in cool water.' However, our basic involuntary response to cool the body when it is overheated is to sweat.

Sweat is mainly water, with salt and other chemicals. Because of its wetness, it is a breeding ground for bacteria and fungi. These organisms grow at an amazing speed, producing toxins that cause body odour, athlete's foot and jock itch. Once the skin is clean and dry and there is little or no sweat, there is little or no chance of these conditions. This is the science behind antiperspirant use.

Controlling perspiration

Apart from self-help measures like bathing regularly, thoroughly drying the skin, wearing cool, clean clothing, 'airing' potentially sweaty feet, removing underarm and pubic hair, and staying in air-conditioned places, we may use chemicals to control offensive organisms and perspiration.

Dusting powders

Medicated powders are excellent for absorbing moisture. They are regularly used in the groin (nappy) area, between toes, underarm and inside shoes. Some powders contain antiseptics like boric acid, absorbent ingredients like cornstarch, antiperspirants like aluminium compounds, and deodorising ingredients like baking soda and zinc oxide.

Deodorants versus antiperspirants

Many consumers confuse antiperspirants (that prevent sweating) with deodorants (perfume plus antibacterial). Look for the word 'antiperspirant' on the container to ensure you are getting just that, or look at the ingredients of the product. They come in the form of aerosol sprays, gels, creams, solid-sticks or roll-ons. Many products contain antiperspirants plus deodorant ingredients.

Deodorants are products we apply to the skin to mask or suppress body odour but not perspiration. Some contain perfumes plus antibacterials like triclosan, or other chemicals which slow down the growth of the odour-causing bacteria. Antiperspirants are a type of deodorant since, by reducing perspiration, they reduce body odour. They attack the root cause of body odour (sweat).

Aluminium compounds like aluminium chloride, aluminium chlorhydrate and aluminium zirconium tetrachlorohydrex gly are the active ingredients of most commercial antiperspirant formulations. They work either by causing the pores of the skin to contract, limiting the amount of sweat, that reaches the surface or they form a gel which plugs the ducts in the sweat glands, preventing the gland from oozing sweat. When the antiperspirant aluminium zirconium tetrachlorohydrex gly reacts with sweat we get the yellow underarm stains on our clothing.

Stay dry, cool and fresh this summer.

Dahlia McDaniel is a pharmacist and final-year doctoral candidate in public health at the University of London; email: yourhealth@gleanerjm.com.