An anti-perspirant contains aluminium salt, a material that forms gels in some of the sweat ducts on the skin once perspiration has started to occur. This reduces the amount of perspiration produced under the arm.

The aluminium salt and the perfume help to combat odour as the aluminium salt reduces the amount of bacteria on the skin and the perfume helps to mask any odour generated.

Most anti-perspirants contain a gel-like ingredient that works to reduce sweat from the skin. It does this by covering the ducts and pores we sweat through - forming a protective layer, in a sense. This can last for several hours, so less sweat escapes through your skin. With time, this protective layer dissolves and the skin sweats as it normally would until more anti-perspirant is applied.

You can use the products several times a day, however, they are designed to last all day. But it would be a good idea to wash the underarm area prior to reapplication to get the benefit of the fragrances.

Rexona formulations have been designed to keep you dry and smelling great throughout the day if used every day. You may choose to use it every morning, after you get washed or before you go out.

The products are dermatologically tested. The test is carried out by an external company on a number of panellists and involves a two-application patch test to assess the comparative irritation potential of the product versus a positive control of detergent solution and a negative control of water; results are assessed by a Dermatologist. Each of the products has successfully undergone this testing.

No. Unilever does not test finished products on animals, and uses human volunteers when testing is necessary.

No. This argument forms the basis for an email that began circulating a few years ago, and it has also appeared in some newspaper articles. However, experts in this field do not agree with this theory for two reasons:

1. The body does not sweat to 'flush out' toxins
2. Anti-perspirants do not alter the body's overall ability to sweat, to any significant degree

The overwhelming majority of toxins, around 95 per cent, are removed from the body by the liver and kidneys. The body sweats to control temperature and not to remove toxins - sweat consists almost entirely of water, with some sodium and fat, none of which are toxic. Also, sweat is produced from some 2 - 5 million sweat glands around the body, and antiperspirants only affect those in the armpit. Surprisingly, there are relatively few sweat glands in the armpit and they produce only about one per cent of the body's sweat - we are just more aware of it because the sweat can't evaporate as easily from under the arm as from other areas of the body. Antiperspirants work by dissolving in sweat to produce a thin coating on the skin that temporarily reduces underarm sweating, but does not alter the body's release of sweat to any significant degree.

Whether the extra heat comes from hardworking muscles in the gym, from over-stimulated nerves due to stress, or from high air temperatures and humidity, sweating is the body's way of naturally regulating its temperature.