One of the most common personal hygiene issues concerns a process that is absolutely essential for human life and yet which is perceived by many to be undesirable and dirty. This process is called perspiring or sweating, and it plays a vital role in maintaining normal health. Amongst the essential functions of perspiring are the elimination of toxins, maintaining the balance of salt levels, and the regulation of body temperature.
Under normal circumstances we are all continually perspiring, losing around one or two pints of liquid a day through our skin. Generally, this evaporates very quickly, and our skin and clothes do not feel or appear to be damp. However, if we exert ourselves by exercising energetically perspiration increases and we realise that we are sweating. The same effect can be achieved through the release of adrenaline due to fear or worry, or because we are in an environment that is too warm for the body.
Experiments have shown that perspiration is almost odourless when fresh, but when allowed to remain on the skin it develops the well-known sweaty odour commonly referred to as BO. Much of this is due to the presence of bacteria that breed in the warm, moist, nutrient-rich conditions created by perspiration. For many years man has been looking for ways to prevent or overcome this smell, and this has lead to the introduction of three main product categories – perfumes, deodorants and antiperspirants.
Mask that Smell!
The use of sweet smelling plants and herbs goes back thousands of years and was once the main method of counteracting noxious odours. Some of these plant materials were very highly prized – of the three precious gifts presented to the infant Jesus by the Wise Men, two were perfumes – Frankincense and Myrrh. In more recent times, but before regular washing became the norm, those who could afford to carried with them a small, specially prepared bouquet of herbs and flowers. Called a nosegay, the principal function of this was to disguise or mask any unpleasant smell that might be encountered during social occasions, i.e. when meeting other people. As we now realise, simply masking a bad smell does not make it go away and does nothing to remove the cause, which is why there is so much interest in our second category – deodorants.
Prevent that Smell!
With our increasing knowledge of microbiology and a greater understanding of how some smells are caused it was only a matter of time before scientists entered the battle against BO. Realising that much of the problem was caused by bacteria breeding on skin and hair that was exposed to perspiration, they figured that the best approach would be to prevent these bacteria from breeding, thereby having a deodorising action. Various ideas were put proposed, and the first commercial deodorant was launched in 1888. Unfortunately, in the quest for ever stronger and more effective deodorants, stronger and more powerful chemicals started to be used.
Some of these chemicals have now been linked to health problems ranging from skin irritation and contact dermatitis from alcohol and triclosan, to more serious problems such as reported lung damage from zirconium salts in some deodorant sprays. These problems lead to more stringent laws about what can be used in deodorants, but many consumers are still concerned about the huge range of synthetic ingredients still used in most commercial deodorants. That these synthetic ingredients are not necessary we shall see later in this article.
Plug the Gap!
The most recent weapons created in the fight against BO were developed in the last 50 years and are known as antiperspirants. Looking at the root cause of the problem, it seems obvious that if you cut off the supply of nutrients needed by the bacteria, they will stop multiplying and the problem will cease.
Based on this theory, a range of chemical antiperspirants was developed to physically prevent sweat from being excreted. Most antiperspirants contain ingredients which react with protein molecules present in perspiration and swell to form a gel-like substance. For these to be effective, it is important that their molecular size is small enough to allow them to enter skin pores so that when they swell and turn to a gel, they effectively block the pores and prevent sweat from being secreted.
Amongst the ingredients that have this property and which are commonly used in antiperspirants are Aluminium chlorohydrate and Aluminium zirconium chlorohydrate. These are both based on aluminium and, like most aluminium salts, they can cause skin irritation. Unfortunately, the inflammation they can cause may spread beyond the areas where the antiperspirant is being applied, leading to more general inflammation. Antiperspirants also have another down-side – not only can they cause the problems mentioned above, but they also prevent the body from eliminating toxins through perspiration, and greatly reduce our ability to regulate body temperature. With three good reasons to avoid antiperspirants, it is no wonder that more and more people are looking for more natural ways to prevent body odour.
Natural Deodorants – a Good Alternative!
One of the most interesting ingredients used in natural deodorants is a naturally occurring mineral salt called Alunite. Otherwise known as Ammonium alum, this is an abundant earth mineral and, along with other forms of alum, forms about 8% of the earth’s crust. It is found in small quantities in many of the foods we eat, and is considered as very safe in personal care and other external uses.
It should be noted that whilst Ammonium alum does contain some aluminium, it is bonded into a molecule that is physically too large to penetrate the skin. This is because the largest molecule that can penetrate the skin has a molecular mass of less than 500 Da, whereas Alunite has a molecular mass of 670 Da – much too large to be able to pass through the skin. Therefore, this ingredient will not block pores nor cause skin irritation in the same way that the aluminium salts mentioned in connection with antiperspirants can.
When Ammonium alum is applied to the skin it acts as a coagulant, constricting protein and thereby reducing the ability of bacteria to thrive. It is not such a powerful antibacterial as some synthetic substances used, but when applied regularly to freshly washed skin it is remarkably effective.
Another interesting ingredient in natural deodorants is Zinc ricinoleate. This is the zinc salt of ricinoleic acid, extracted from the seeds of the castor oil plant. Zinc ricinoleate does not inhibit normal perspiration, and will not interfere with the natural flora of the skin. Instead, it ‘fixes’ the odours produced by bacterial decomposition in sweat so that they cannot be released into the atmosphere and cause the characteristic sweaty smell.
