This old question was recently resurrected when UK researchers highlighted the potential risks associated with the preservatives parahydroxybenzoic acids, or parabens, in deodorants.
Parabens are used in a wide variety of cosmetics, and studies suggest they are oestrogenic. Used in formulas absorbed into the skin, such as body, face and suncreams, it is speculated that these xenoestrogens (from outside the body) could build up and cause health problems.
Speculation came closer to reality when researchers at the University of Reading found traces of parabens in every single tumour sample taken from a small group of women with breast cancer (J Appl Toxicol, 2004; 24: 5-13).
They concluded that the chemicals had seeped into the tissue after being applied to the skin, probably via deodorants. As parabens are oestrogenic, they can act as fuel for human breast tumours.
The UK's Cosmetic, Toiletry and Perfumery Association was quick to counter that parabens have a good safety record, but it is only recently that anyone has bothered to examine how these widely used chemicals behave in the body. So, cosmetic companies have, for years, been able to broadly interpret the absence of evidence as evidence of safety.
From the outside in
Body odour can be caused by bacteria in your armpits, but can also reflect what's inside your body. What you eat and how 'polluted' your body is by toxins and allergens may also be involved. Deodorants combat the problem of body odour at skin level, using a mixture of strong perfumes and antibacterial ingredients. Antiperspirants block the pores and prevent sweat from leaking out of the armpits.
Today, a vast range of deodorants, antiperspirants and antiperspirant/deodorants is available in a variety of formulations - creams, gels, roll-ons, solids and sprays. A quick look at labels will tell you that there isn 't much difference between them. Antiperspirants and deodorants typically contain moisturisers, solvents, preservatives (like parabens), synthetic scents and antibacterial agents such as triclosan (absorbed through the skin and known to cause liver damage in animals).
Some contain dibutylphthalate (DBP), a hormone-disrupting chemical implicated in reproductive abnormalities.
However, until the news about parabens, it was the aluminium content of antiperspirants that was the major cause of concernMost antiperspirants contain some form of aluminium, usually aluminium chlorohydrate, aluminium zirconium, aluminium chloride, aluminium sulphate and aluminium phenosulphate. No one knows exactly how aluminium compounds reduce underarm wetness. They may prevent sweating by clogging sweat ducts. But clogging leads to pressure from the sweat buildup inside the ducts, and it 's thought that this may cause the sweat glands to stop secreting.
Alternatively, they may perforate the sweat glands so that sweat seeps out into the surrounding tissues rather than exit-ing through the surface of the skin. Or they may block the transmission of nerve impulses that activate sweat glands. Either way, aluminium is absorbed through the skin, albeit superficially. The link between Alzheimer 's disease and aluminium has raised considerable debate over the safety of using aluminium compounds in deodorants. Yet, only one study (J Clin Epidemiol, 1990; 43: 35 -44) reports a link between Alzheimer's and a lifetime's deodorant use. No other studies have been conducted to confirm these findings.
A look at the incidence of breast cancer among 400 US women suggests it may be a combination of underarm shaving and deodorant use that allows chemicals to seep into breast tissue (Eur J Cancer Prev, 2003; 12: 479 -85). Those who shaved three times a week and applied deodorant at least twice a week were almost 15 years younger when diagnosed with the cancer than women who did neither. The res-earchers suggested that aluminium compounds could be a breast-cancer trigger. Certainly, aluminium-based deodorants are a major cause of skin irritation-reason enough to be approached with
caution by users. Aluminium zirconium products are known to cause granulomas (small nodules of chronically inflamed tissue) under the arms with prolonged use.
Alum vs aluminium
Rock crystals are the newest alternative to aluminium-containing antiperspirants. Some of these are made from magnesium sulphate while others use alum. These products often claim to be free of alumin-ium chlorohydrate, yet alum by its other name is aluminium sulphate. Manufac-turers say that, as this is a much larger molecule than aluminium chlorohydrate -which is true-it cannot pass via the skin. However, aluminium chlorohydrate is much less soluble in water (sweat) while sulphates are highly water-soluble, so alum may more readily break down into its component parts in a warm sweaty armpit. So, is aluminium then absorbed into the skin? With no research evidence, no one knows. Although it is unlikely, the widely promoted idea that all deodorant crystals are aluminium-free may need more careful scrutiny in future.
There is a growing consumer desire for safer alternatives to the usual high-street antiperspirants and deodorants. Unfortunately, there is, as yet, no compound other than aluminium for making an effective antiperspirant. But safer alternative deodorants are not difficult to find.
These are made of natural antibacterial agents and fragrances that limit underarm odour. They come in forms ranging from solids and crystals to sprays and roll-ons, and are available at chemists, healthfood stores and even supermarkets.
For our first PROOF! Panel investigation, we asked 10 men and women to road-test eight deodorants. Each product was used over a five-day period; participants kept a diary of how well each one worked as well as made a note of any other observations - such as how quickly the product dried, any sensitivity reactions or how easy it was to use.
Given their lack of synthetic chemicals, natural deodorants perform differently from conventional ones. The first thing most of our panel noticed was that (except for the sticks) most took much longer to dry. Often, they felt sticky on application and few lasted the entire day.
On the plus side, none left discolorations on clothing, and only two contained suspect ingredients. None of the products resulted in any sensitivity reactions. As for effective, long-lasting odour control, two clear leaders emerged: Green People 's Gentle Control and Tom's of Maine Nature's Deodorant. Jason's Tea Tree Oil Deodorant Stick came close third (see the table on p 3 for a summary of the results).
In general, our panel's comments suggest that we still have some way to go towards producing totally effective, long-lasting, pleasant alternatives to conventional deodorants that users would feel confident to use in any circumstances and in any weather.
Most of the roll-on and spray formulations were fragranced with natural essential oils. Many of these oils, such as tea tree, rosemary and sage, also have a proven track record as antibacterials. Several of our panel expressed concerns that these natural scents would not be strong enough to last the whole day (and into the night), or during exercise. While the alum compounds (in the two crystal forms, the PitRok Spray and Green People 's roll-on) are established antibacterials, there was some concern that, without a strong scent, body odour would soon become apparent. In general, this was not the case. Indeed, the more strongly fragranced products were unpopular among some panel members.
Non-aerosol sprays by Weleda and PitRok also raised some issues. The biggest complaint was that the small nozzle size made it necessary to use several sprays, making the product less economical. With only 30 mL in Weleda 's case, this could prove expensive (though half the panel felt that this product offered effective odour control over the course of the day).
Likewise, while both PitRok and Tawas crystals provided good initial odour control, the majority felt that the effect was short-lived. One commented, ''I wouldn 't feel confident using this for sport or a long night out''; another said: ''Long-lasting? It never started lasting!'' This seems to sum up how most users viewed the crystals.
While we've included prices, cost-effectiveness is impossible to assess as the deodorants came in different forms and use can vary enormously from one person to another. Also, while the crystals were more economical than, say, roll-ons, they were also deemed less effective.
Gentle Control Rosemary *****
Manufacturer: Green People
Price: lb6.45 (75 mL)
Made from organic ingredients, this roll-on claims to reduce bacterial growth with the use of rosemary essential oil, grapefruit seed extract, witch hazel and ammonium alum. This was the only product which all our panel members agreed provided effective body-odour control. It was also the one fragrance that got the most positive votes. Cost: 8.6 p/mL.
Nature's Deodorant ****
Manufacturer: Tom's of Maine
Price: lb3.75 (60 g)
This is an easy-to-use gel-type stick deodorant. Women on the panel used Calendula and the men used the more masculine Woodspice. Opinions were divided as to whether these scents were pleasant or far too overpowering, but
both were considered to have lasted throughout the day. The stick is a familiar form for a deodorant, and there was lots
of information on the label. Cost: 6.2 p/g.
Tea Tree Oil Deodorant Stick ****
Price: lb3.99 (70 g)
This is a solid deodorant that many of
our panel found a little sticky and 'soapy' on application. It also took longer than most to dry. Two panel members felt that
it made them smell worse than using no deodorant at all and that this "rancid" smell was difficult to get rid of. But most
of our testers found it an effective alter-native in spite of a somewhat medicinal smell. Cost: 5.7 p/g.
Lemon Verbena Deodorant ***
Manufacturer: Avalon Organic Botanicals
Price: lb3.69 (85 mL)
This American import is 76-per-cent organic ingredients. Included in its interesting list of ingredients are lemon verbena, Echinacea, lavender, Calendula (mari-gold), lemon balm, sage, witch hazel, myrrh, aloe and grapefruit seed extract. But it also contained parabens -the only one of our test samples to do so. While several users found this product useful, it was disappointing to see those unnecessary preservatives. Cost: 4.3 p/mL.
Sage Deodorant ***
Price: lb2.60 (30 mL)
This product uses an alcohol base to provide an astringent action while lemon juice and sage extract fight bacteria. Two of our users (one man and one woman) felt a slight sting on application that was even worse on a shaved armpit. The smell left no doubt as to its herbal origin, and most users found it unpleasant. Everyone commented on the small size of the bottle, which was felt to make this product very uneconomical -especially since you had to use several sprays to adequately cover the underarm area. Cost: 8.6 p/mL.
Natural Deodorant Crystal ***
Price: lb6.95 (120 g stone)
This potassium-alum crystal comes in a pretty wicker basket. The label claims that this will be effective for 24 hours or more, but this was not the experience of our panel members. In fact, opinion was divided as to whether this product had any effect at all. Most felt that it was better
than the PitRok crystal, and the PitRok push-up container is a much more practical concept. Several users never found the rather obscure instructions that came with this product. Cost: 5.79 p/g.
Natural Crystal Deodorant **
Price: lb5.95 (100 g)
This is a pure ammonium-alum crystal in a plastic push-up applicator. This was a more convenient way to use a deodorant crystal than Tawas ', and many of our panel preferred this to the unpackaged, and somewhat slippery, stone. But, sadly, few found this effective, while those who did felt that its odour-fighting effect was very short-lived. Cost: 5.9 p/g.
Natural Spray Deodorant *
Price: lb3.95 (100 mL)
This hand-pump spray is based on the same natural mineral salts as the solid, but uses added skin conditioners (aloe vera, grapefruit seed extract and Calendula). Unlike Weleda 's, this has no alcohol, but it does contain chemical preservatives (2-bromo-2-nitroproane-1,3,-diol and phen-oxyethanol) that may cause allergic/sensitivity reactions in some. Cost: 3.9 p/mL.
If you prefer using conventional antiperspirants and deodorants, there are ways to make your choices safer and less likely to irritate your skin. Consider the following:
* Switch to a solid or stick variety. It is less emollient and so less likely to aid the absorption of ingredients into the skin. Sticks also tend to produce less skin irritation
u Never apply antiperspirants or deodorants to broken or newly shaved skin
* If you don't sweat heavily, use a deodorant rather than an aluminium-containing
* Avoid aerosols, which produce easily inhaled clouds of neurotoxic and reproductive toxins propane, butane and isopropane as well as planet-poisoning HCFCs
* Avoid coloured products. They don't aid dryness, and the synthetic colours are easily absorbed into the skin and may be carcinogenic.