Could your everyday deodorant be doing you harm? B+S puts it to the test

DEODORANT has been part of our grooming regimen for more than 100 years, but questions have now risen about their "side effects".

Dilvin Yasa looks at some scientific facts and common myths behind these often debated products. Plus, we trial some of the new natural alternatives on the market. Picture: Shutterstock.

DEODORANT and antiperspirants have been part of our grooming regimen for more than 100 years, but about 15 years ago, questions arose about their "side effects".

One popular theory was the aluminium in antiperspirants prevents the body from expelling toxins, which then clog up the lymph nodes and cause breast cancer. While it's true that sweating is one way that your body gets rid of toxins, Kathy Chapman of Cancer Council NSW says it's worth noting that "breast cancer starts in the breast and spreads to the lymph nodes, not the other way around".

Another theory was that the aluminium is absorbed by the skin, affecting the blood brain barrier and linking it with the onset of Alzheimer's disease.

The stories varied from source to source, but what the Cancer Council claims began as a hoax email soon trickled down to websites and news outlets, causing widespread suspicion of these products, and that remains today.

A FOCUS ON ALUMINIUM

Aluminium has been the common element of concern. This was, in part, prompted by a 2007 study of women with breast cancer that found higher levels of the chemical in areas of the breast nearest the skin, prompting the authors to ponder a possible link. Similarly, a series of studies in the 1960s suggested that aluminium had a tendency to accumulate in the brain tissue of Alzheimer's patients.

Both ideas were soon disproved. The Alzheimer's theory couldn't be replicated in later studies, and scientists concluded there was "no causal relationship" shown between deodorant use and the disease.

The breast cancer study was found to be flawed as not only was it based on just 17 women, but it didn't compare levels of aluminium in their breasts to other parts of their bodies or to levels in women who didn't have breast cancer. A larger study of 1606 women satisfied researchers that deodorant use didn't increase the risk.  

HORMONE INTERFERENCE

Lab-based testing and animal models have found that an oft-used antibacterial agent in deodorants, called triclosan, can mimic or interfere with hormones. In one study, published in the journal Chemical Research in Toxicology, researchers found it promoted growth of human breast cancer cells in lab dishes and breast cancer tumours in mice, while other animal studies showed it disrupted hormonal function, and reduced heart muscle function by 25 per cent.

While there's no evidence yet that triclosan has the same effect in humans, the EU has restricted its use in personal products. The US state of Minnesota recently banned it entirely. It's still in use in Australia and can be found in some deodorants.

DID YOU KNOW?

It takes a higher temperature to make women sweat than men.

NATURAL DEODORANT ROADTEST 

Product: A BIT HIPPY NATURAL MINERAL roll-on($7.50, abithippy.com.au)
How it stacks up: Easy to apply but top-ups needed. Uses essential oils  to stop "odour-causing bacteria".

Verdict: 7/10

Product: Black Chicken Remedies Axilla DEODORANT PASTE ($7, blackchicken.com.au)

How it stacks up: This doughy paste is applied with fingers. It has an uplifting smell with lasting odour block.

Verdict: 9/10

Product: SCHMIDT'S lavender and sage DEODORANT ($14, iamnaturalstore.com.au)

How it stacks up: A hard paste that keeps you dry and is applied with a mini shovel-like tool. Scent is fresh.

Verdict: 8/10


Product: LAVANILA the healthy deodorant ($24.95, iamnaturalstore.com.au)

How it stacks up: A dry roll-on that glides on nicely, but the odour-masking effect wasn't as consistent.

Verdict: 7/10

Ask the DOCTOR... WITH DR CINDY PAN

What's involved in allergy testing and when should it be done?

These tests can be used to determine if a particular substance triggers an allergic reaction, symptoms of which range from sneezing, asthma, itchy eyes and skin rashes to the more serious anaphylaxis, which can lead to life-threatening breathing difficulties.

The main type of testing is a skin-prick test. This involves administering a tiny drop of solution containing an allergen extract into the skin using a tiny sterile lancet. Various allergens will usually be tested at once by creating a grid of pinpricks on the inner forearm. The allergy specialist then looks at the size of the local reaction, if any, around each pin prick within 20 minutes of application.

Any positive results, which show in the form of a raised weal or flare, are measured and the allergen responsible is carefully recorded and discussed.

It's important to avoid taking any antihistamine-containing medication in the week leading up to the test as these may damp down any potential reaction.

At times when a skin-prick test is inconclusive or not possible - such as when a skin condition like eczema interferes with skin testing - a blood test for allergen specific immunoglobulin E antibodies (formerly known as RAST or a radioallergosorbent test) may be done.

The range of allergens to test for will be decided by your doctor depending on your symptoms, concerns, history of exposure and suspected triggers.

When contact dermatitis is suspected, a patch test may be done, in which a small amount of a standardised allergen paste is applied to intact, rash-free skin, usually on the back, using hypoallergenic tape. Substances tested vary depending on what's suspected, and will typically include metal, cosmetic preservatives or various plants. The region must be kept dry and the tape left intact for 48 hours so the local skin reaction can be monitored at various intervals. A reaction is usually in the form of an eczema-like rash.

When the cause of a severe allergic reaction hasn't yet been established, a "challenge" test may be performed. This involves suspected food or medications being administered under specialist supervision, with resuscitation facilities readily available in case of anaphylaxis.

Your GP and allergy specialist can advise which test is most appropriate for you, depending on your symptoms and the sorts of exposures and triggers you've noted. They'll also help you understand the interpretation of any test results.

This post originally appeared on Body & Soul.