A pheromone is a substance sign that activates an innate response in other members of the same species. These substance messengers leave the body and have a direct impact hormone levels or behavior. Human pheromones are believed to perform the same way.

Most studies about pheromones have to do with a woman’s menstrual cycle and how they coordinate with other women’s menstrual cycles through undetected odors that the body sends out during this time. Exposure to the sweat of another woman, that was collected during different times of the month, was done to the women in the group.

The conclusion was that two pheromones were involved in the process. One for lengthen ovulation and the other for shortening it. The results of the study have been questioned about the validity over recent years.

It is also believed that the armpit of a male releases pheromones too. The theory is that the sweat from men has pheromones. Studies regarding menstrual cycles that are not regular have shown that exposure to extracts from a males armpit can cause the periods to become normal.

Androstadienone that can be found in a males sweat includes higher amounts of cortisol in women. This substance can be picked up by the nose and may have an effect on the endocrine balance in the opposite sex.

Studies have also shown that a certain chemical in women’s perfume increases the likelihood of intimate contact with males. Suggestions that this study is flawed have also surfaced.

The attraction of a mate that one is not related to may be possible because of a connection with the immune system and pheromones. Research shows the possibility of two distinctive smells being created by the body that cause the brain in homosexual and heterosexual men to respond differently.

Since the theory is that the scents result in sexual arousal, it stands to reason that homosexual men react in the same manner that heterosexual women do to the scents. To further test the theory, homosexual women were included in the research. The same findings resulted as the prior study. So, sexual orientation may have more to do with pheromones and biological sources than originally thought.

Body sprays and perfume marketers have used pheromone claims to boost sales by saying sex pheromones are included in the spray. Theoretically, these pheromones are similar to aphrodisiacs. It is important to note that research has been able to prove, beyond a shadow of a doubt, that pheromones play a definitive role in sexual attraction.