More bad news for Covid-19 sufferers as study reveals the virus can put you off sex

Losing your sense of smell – one of the symptoms of Covid-19 – can put you off sex, a new study reveals. 

US researchers found a link between a loss of smell, known as anosmia, and decreased sexual motivation and emotional satisfaction in older US adults. 

The experts say the sense of smell plays 'a uniquely strong role' in sexual motivation – and that both are 'intimately linked'. 

Researchers only looked at adults aged 65 and older, meaning the link could only get stronger as we grow older and may be less pronounced in young adults. 

Despite this, researchers say potentially treatable causes of sensory loss like should be addressed by clinicians to 'improve quality of life' – in other words, their sex life. 

What is anosmia? 

Anosmia is the medical name for a condition in which someone suffers a complete or partial loss of their sense of smell.

The most common single cause of the condition – temporary or permanent – is illnesses which affect the nose or sinuses, such as polyps which grow in the airways, fractured bones or cartilage, hay fever or tumours.

It is different to hyposmia, which is a decreased sensitivity to some or all smells. 

Around 3.5 million people in the UK are affected by the condition, along with nearly 10 million in the US. It is surprisingly common and affects between three and five per cent of people.

Head injuries and nervous system diseases like Parkinson's or Alzheimer's may also contribute to the condition by damaging nerves in the nose which are responsible for detecting smells. 

As we grow older, our sensory functions steadily decline, with various impacts for older adults. 

Previous research has already suggested that smell disorder patients complain about impairments in their sexual life. 

To learn more, researchers investigated the effect of a loss of the olfactory function, or sense of smell, has on older people's sexual desire and satisfaction. 

The team, which also included an expert from Brigham and Women's Hospital in Boston, worked with a sample of 2,084 older adults in the US, all aged 65 or older. 

The adults, described as a 'nationally representative sample', were recruited from the National Social Life, Health, and Aging Project, an ongoing longitudinal, population-based study of health and social factors.    

The experts measured their olfactory sensitivity with smelling sticks and their frequency of sexual thoughts and sexual activity through a questionnaire, as well as satisfaction with their most recent sexual relationship. 

'Decreased olfactory function in older US adults was associated with decreased sexual motivation and less emotional satisfaction with sex, but not decreased frequency of sexual activity or physical pleasure,' the researchers say. 

However, a decrease in sensitivity of smell did not indicate a decreased frequency of sexual activity or a decrease in physical pleasure. 

Analyses were adjusted for age, gender, race, education, cognition, comorbidities and depression – but the team could not determine causality, meaning it's not known if loss of smell causes decreased sex drive or vice versa. 

'Our research shows a decline in olfactory function may affect sexual pleasure in older adults,' said study author Jesse K. Siegel at the University of Chicago.

'Therefore, treatable causes of sensory loss should be addressed by clinicians to improve sexual health.' 

The experts say this might be due to 'evolutionarily-conserved' neurological links between olfaction and sexuality. 

'Olfaction has a strong, evolutionary-conserved connection to the limbic system, which plays a critical role in processing emotions and sexual motivation,' Siegel and her team say in their paper, published in The Journal of Sexual Medicine. 

'Neurons in the olfactory bulb also project directly to the hypothalamus, another key mediator of sexual motivation.'  

Study author Dr Jayant Pinto, also at the University of Chicago, told MailOnline that olfactory system is connected to centres in the brain that allow the experience of pleasure.

'These connections are ancient in that lower organisms need to detect chemicals in the environment [such as] nutrients to feed, toxins to avoid,' he said. 

'As sexuality is essential for reproduction, this too depends on sensory input. 

'Thus, the associations we find may be signs that these two old parts of our nervous system physiology are connected. 

'The benefit would be more efficient mating and more progeny, in an evolutionary sense.'

The study was performed pre-Covid, meaning it's also not known how loss of smell in people with Covid specifically is linked to sexual desire. 

The three most common symptoms of Covid-19 are a high temperature, a new and continuous cough, and a loss or change to sense of smell or taste. 

Public Health England also lists less several less common symptoms, including aches and pains, headache and a skin rash.   

Generally, loss of sense 'may go back to normal in a few weeks or months', according to the NHS, and treatment with steroid nasal sprays or drops might help for people with sinusitis or nasal polyps. 

However, people who have lost their sense of smell specifically due to Covid may not get it back two months later, a study from January suggested.

A study from last July also found one in ten people who lose their sense of taste and smell with the coronavirus may not get it back within a month.