Nearly four million British women - and around half as many men - are said to suffer from low libido. If your sex drive has stalled and it's not due to stress, hormonal changes or relationship issues, maybe poor posture or one of these other bizarre libido-zappers is to blame?
See also: Natural alternatives to Viagra
1. Cleaning the house
Doing the housework could be ruining your sex life – but not in the way you think. Chemicals found in cleaning products (as well as food packaging, and personal-care products including shampoo and cosmetics), could be having a negative impact on women's libido, according to research presented at the American Society for Reproductive Medicine.
Phthalates, a softener which makes plastics bendy, has already been linked to lower sexual function in men. Dr Emily Barrett, of the University of Rochester School of Medicine, told the Telegraph: "We are learning that phthalates are endocrine disruptors, they interfere with normal hormones in the body – testosterone and it looks like oestrogen as well.
"And we know that both testosterone and oestrogen are really important for many things, including libido, so we were interested in looking at whether women who had higher levels of these chemicals in their bodies have a lack of interest in sex."
2. Cold and flu remedies
A stinking cold is a guaranteed passion killer – but taking over-the-counter cold and flu remedies could lower your sex drive even more. Dr John Tomlinson, a GP specialist in men's sexual health warns that cold remedies which contain diphenhydramine or pseudoephedrine can cause erectile dysfunction, as well as lowering your sex drive.
"Why this is so is not clear, but I have certainly seen it in my patients. It won't happen to everyone, but if your libido is already fragile, then it could knock you off your perch," he told the Daily Mail.
It seems antihistamines could have a similar effect. A separate study from the Cleveland Clinic in Ohio found that antihistamines might lead to problems with ejaculation for men and lower the sex drive of both men and women. It's thought that the drug may interfere with the part of the nervous system connected with sexual arousal and orgasm.
3. Low iron levels
An estimated 25% of British women don't get enough iron from their diet – which is bad news when it comes to the bedroom. Iron deficiency reduces the quality of blood flow and so saps energy. And if you're always tired, you're not going to feel like having sex.
Take iron supplements or eat more red meat. As well as containing iron, red meat is a good source of zinc, important for the production of the sex hormone testosterone, which women also need for sexual desire. If you're not a meat-eater, up your zinc intake with beans, nuts and oysters.
4. Blood pressure pills
Many prescription medicines (including anti-depressants) can have an effect on your libido. If you're taking blood pressure pills, you may notice a reduction in sexual desire, and may also experience erectile dysfunction. This is because they reduce heart rate and blood flow, which means less blood gets to the genitals.
According to a review of blood pressure medication in the International Journal of Clinical Practice, the worst offenders are diuretics and beta-blockers such as propranolol and atenolol. Speak to your doctor if you're concerned and never stop taking medication without consulting your GP first.
5. Having an apple-shaped figure
Women who carry weight around their tummy rather than their hips and bottom are likely to have a lower libido. Dr Mark Vanderpump, consultant endocrinologist at the Royal Free Hospital in London told the Daily Mail: "Increased waist circumference, or being an apple shape, reduces the amount of a protein called sex hormone-binding globulin (SHBG) which is produced in the liver.
"This protein is vital as it attaches itself to testosterone and transports it around the body. If you have less of the protein you'll have a lower concentration of testosterone, too."
6. Taking the contraceptive pill
You may enjoy sex more knowing you don't have to worry about getting pregnant, but ironically, taking the pill can cause a loss of libido.
German researchers at University Hospital of Tübingen studied more than 1,000 women and found that those who used a hormonal method of birth control had lower levels of libido and arousal.
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