1. The Pill
Evidence has been mixed on this, but a 2010 study of over 1,000 women found that those who took oral contraceptives had lower levels of both sexual desire and arousal than those who didn’t. This bolsters widespread anecdotal evidence — many women have said that the Pill killed their desire to have sex.
2. Lack of Sleep
A 2011 study found that getting less than five hours of sleep a night was associated with a significant drop in men’s testosterone levels, which in turn can lead to low sex drive. It’s reasonable to assume being sleep-deprived isn’t awesome for women’s libidos either.
3. Eating Too Much
Saturated fat, that is. Sexual medicine expert Dr. John Mulhall told NBC that too much of this type of fat could clog arteries and reduce blood flow to sexual organs.
4. Not Eating Enough
Low sex drive is one of the side effects of extreme calorie restriction. Calorie restriction is a fancy term for eating 10 to 50 percent fewer calories than normal, which has been touted in the past few years as a way to increase longevity. And while most dieters probably aren’t cutting their calories in half, being starving probably isn’t great for the libido (especially if you have no energy).
A 2011 study found that the hair-growth drug can cause low sex drive and erectile dysfunction in men.
This should be surprising to exactly no one. In a 2010 study of postmenopausal women with low sex drive, “stress or fatigue” was the most common reason they listed for their lowered libido. Sixty percent of them said those factors had influenced their sex drive for the worse.
While it’s not always clear which way causation goes, research suggests that depression can lead to low sex drive. In one study, 70% of depressed but unmedicated patients reported loss of interest in sex.
But several studies, including one from 2010, have found a link between (some) antidepressants and sexual dysfunction.
Brooke Faught, a nurse practitioner at a sexual dysfunction clinic, told USA Today that anemia could cause low libido in women. Luckily, an iron pill might be able to fix this particular sex-drive-killer.
10. Being In a Long-Term Relationship
A 2012 study found that women tended to lose sex drive the longer they were in monogamous relationships (men in the study did not have this problem). However, monogamous women shouldn’t worry too much — the study was limited to 18-25-year-olds, and was relatively small. Also, the study authors noted that because of social pressure, women might understate their sex drive while men might overstate theirs.