Skip to main content

Nearly Half of Antiperspirants Exhibited Unsatisfactory Efficacy Beware of Residual Stains on Clothes to Avoid Embarrassment

  • 2021.06.15

The hot summers in Hong Kong often leave people drenched in sweat. Many people, therefore, use antiperspirants and deodorants to reduce perspiration or body odour. The Consumer Council tested 11 antiperspirants and deodorants and the results showed that the models generally performed well in terms of odour removal. However, they showed considerable disparity in antiperspirant efficacy. 2 models could easily stain the clothes after use, increasing the chance of disposal as the consumers loathe the stained clothes.

In collaboration with International Consumer Research & Testing (ICRT), the Council tested 11 antiperspirants and deodorants, including 7 roll-on antiperspirants, 2 aerosol antiperspirants and 2 normal deodorant sprays. Their prices ranged from $20.9 to $99.9. The test covered antiperspirant and deodorant efficacy, textile residues, user feedback as well as the environmental performance of product packaging. The Council also inspected the product labels of all the models.

Antiperspirants usually contain aluminium or zirconium compounds that function to block the sweat glands to achieve the temporary effect of inhibiting perspiration. The test was conducted by 20 female panellists who exercised for 15 minutes after applying each model 3 times, and the amount of sweat post-workout was then measured and compared with that when no antiperspirant was used. The 9 models of antiperspirants varied in antiperspirant efficacy. Nearly half (4 models) had unsatisfactory results and received a score between 1 to 2 only. The other 5 antiperspirants scored between 3 and 5. As the 2 deodorant models are not designed for sweat reduction, they do not contain aluminium compounds and were found to be relatively weak in inhibiting sweat secretion. They only scored 2 and 1 respectively.    

  Antiperspirants and deodorants generally claimed that they could be used for odour removal. In the deodorant efficacy test, the test panellists were first asked to apply each model. After 24 hours, pads were placed under their armpits for 4 hours. 3 scent specialists then compared the intensity of odour from the pads with that under the same conditions but without the application of any model. The test results showed that all models demonstrated good deodorant efficacy and scored between 4 and 5. 

Antiperspirants and deodorants may leave stains on clothes. The test panellists were asked to wipe their armpits with a piece of black cotton cloth and black polyester cloth 30 seconds after applying a fixed amount of models respectively. The stains on the cloths were then examined. The test results showed that an aerosol antiperspirant gave the worst overall performance, leaving the most obvious stains on both cotton and polyester and managed to score only 1.5 (cotton) and 2.5 (polyester) respectively. Besides, another antiperspirant left relatively noticeable stains on cotton and only received a score of 2.5 in this test. 2 deodorant models achieved a score of 3.5 and 5 respectively. The stains on all the cloths appeared to reduce after rinsing, indicating that laundry would help wash away the stains on the sampled cloths.

In addition to antiperspirant/deodorant efficacy, consumers should also consider whether the product packaging adheres to sustainable and environmental protection principles when choosing antiperspirants or deodorants. With reference to Europe’s Ecolabel packaging requirements for rinse-off products, the residual quantity (or product loss) and the Packaging Impact Ratio (PIR) of each model were measured. The residual quantity in the container must be less than 10% of the total weight of the product. However, less than 90% of the content could be used from the 2 roll-on antiperspirants’ containers and they scored only 1.5. The PIR of the models ranged from 0.2 to 2.1, and 5 models in glass containers recorded a relatively higher PIR value. 2 models in aluminium containers had lower PIR values and weighed less than the other models. As their material and transport costs were also relatively lower, it helped to reduce the cost of waste management. 

Upon reviewing the product labels of all models, the Council found that 4 models did not list their ingredients on the product packaging. Among these models were 3 antiperspirants, and although 2 of them offered clear descriptions on their product websites, consumers could not obtain the most important information from the product labels immediately. 1 deodorant only listed its ingredients in Japanese on its plastic container, which made it difficult for local consumers to comprehend its contents. All models did not state the amount of ingredients on their labels. Although there is no regulation in Hong Kong that stipulate that cosmetic products must include their ingredients on product labels, the Council emphasises that product labels provide important information for consumers. Manufacturers should enhance the transparency of product information, such as whether the products contain antiperspirant agents, preservatives or allergenic fragrances, so as to help consumers make informed choices.

In addition to using antiperspirants or deodorants, consumers can wear loose and breathable clothes to let sweat evaporate more easily. Reducing the intake of food with heavy scents, e.g. curry, garlic and other spicy foods can also help reduce body odour. When choosing and using antiperspirants or deodorants, consumers should pay heed to the following:

- Apply antiperspirants after shower or before sleep. The aluminium compounds in antiperspirants require time to coagulate with sweat on top of sweat glands to form gels that reduce perspiration. Consumers do not need to re-apply antiperspirants during daytime. They can wait until night-time to do so;

- Apply antiperspirants for a few consecutive days for better antiperspirant efficacy. After discontinuing the use of antiperspirants, having showers can gradually wash away the gel on top of sweat glands;

- Apply deodorants before going out, before doing exercise or after showering. Apply them on dry skin for a more refreshing touch and a better effect, and re-apply during daytime when necessary; 

- Stop using antiperspirants or deodorants when skin lesions or diseases, e.g. eczema and folliculitis are found in the armpits. Avoid applying them immediately after cuts, shaves or hair removal to avoid irritation to the skin;

- Check the product ingredients carefully when itchiness or other allergic reactions occur. Avoid contact with ingredients such as aluminium, fragrances or preservatives to reduce the risk of allergic reactions. 

The Consumer Council reserves all its right (including copyright) in respect of CHOICE magazine and Online CHOICE.