Libido: gut bacteria spoiling the fun

Loss of libido is a sexual disorder with multiple consequences, including reduced quality of life, low self-confidence and self-esteem, and a loss of connection with one’s partner. Doctors use the term “hypoactive sexual desire disorder” (HSDD) when a deficiency or absence of sexual desire causes marked distress or interpersonal difficulties. This combination of symptoms (low desire and associated distress) is present in up to 10% of American women, with similar prevalence rates seen across the globe.

The gut microbiota has already been implicated in certain mental and neurological conditions and recent studies suggest it may play a role in loss of libido and HSDD, which are partly regulated by the brain.

Bacteria, emotions, and sexuality

To find out more, researchers compared the stool of 24 women with HSDD to that of 22 women with normal libido. In the HSDD subjects, they observed a lower abundance of certain bacteria, while others, such as Lactobacillus and Bifidobacterium, increased in number. The greater the differences in abundance compared to the microbiota of the women with normal libido, the greater the drop in sexual desire. More research is required to understand the mechanisms at play, though gut bacteria are thought to secret small molecules into the body that may influence the brain. The stakes are high, since these still tentative results may one day lead to improved management of low libido in women.

Serenity or desire, do we have to choose?

The authors also point out that high levels of Lactobacillus and Bifidobacterium–which signal a loss of libido–have previously been associated with a reduction in aggressive thoughts and feelings of sadness. They believe everything may be linked: anger or stress could represent a prelude to sexuality, particularly since these emotional states generate arousal that can then turn into desire. In other words, we may have to choose between serenity and libido!