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Odor & SweatEvidence check
Women are often said to have keener noses, and the research mostly agrees, by a small margin. A review of smell tests in thousands of people found women outperformed men on every measure, though the differences were small. A brain study counted 43% more cells in women's smell centers. Women also picked out their own body odor far more often than men. Here is what that means for body odor worry.
Odor & SweatEvidence check
If you've noticed men in your spin class drenched while you're merely damp, there's research behind it. In lab studies, women and men sweated about the same during lighter exercise, but at harder efforts men's sweat glands put out more. Training raised sweating in both sexes, more so in men. Sweating more doesn't mean you smell more, though. Here is what the studies show.
Sleep & NighttimeEvidence check
Streetlights, early sunrise and a partner's reading lamp can all reach your eyes at night. In a UK study, young adults who wore an eye mask for a week did better on memory and alertness tests than in a week without one. In hospital intensive care units, reviews found eye masks and earplugs improved sleep. Here is what the research shows, who it fits, and what to try.
Breath & MouthEvidence check
Some women notice their breath seems worse at certain points in the month. In a survey of 1,089 women, about 12% thought their breath was tied to their cycle. Two small lab studies found sulfur gases rose around the period in one and at ovulation in women with gum disease in the other. Here is what they found and how to check your own pattern.
SkinEvidence check
A bad night shows on your face, and studies back that up. In Swedish experiments, people photographed after a night without sleep were rated as more tired, less healthy and slightly less attractive, with darker under-eye circles, paler skin and more fine lines. A US study of 60 women found poor sleepers had more signs of skin aging and slower skin barrier recovery. Here is what the research shows.
Odor & SweatEvidence check
Some women notice their underarm smell seems different at certain times of the month. Early studies suggested men rated women's scent as more pleasant near ovulation, but the effects were small. The most careful study so far, published in 2024, tracked women over 10 days around ovulation with hormone tests and chemical analysis, and found no convincing change. Here is what that means, and how to track your own pattern.
SkinEvidence check
Cocoa butter and oils are the classic way to try to prevent pregnancy stretch marks. Two placebo-controlled trials found cocoa butter didn't work: in Lebanon, 45% of women using it got stretch marks against 49% on a look-alike lotion, and in Jamaica, 44% against 55%, a difference too small to count. A Cochrane review of six trials found no high-quality evidence for any cream. Here is what the trials show and what's left to try.
SkinEvidence check
Milk and sugar get blamed for breakouts more than almost anything else. Two small trials found a low-glycemic diet cut pimple counts in young people, and studies that asked people what they ate link milk with somewhat higher odds of acne. None of it was done in adult women, and UK guidance says there isn't enough evidence for an acne diet. Here is how to test a food on yourself.
PeriodsEvidence check
Many women with endometriosis try diet changes, from cutting gluten to adding fish oil. A review found 9 human studies of diet for endometriosis; most reported benefits, but all had moderate or high risk of bias. In a placebo-controlled trial in young women, vitamin D and fish oil did no better than placebo for pain. A large nurses' study linked more omega-3 fats with lower risk and more trans fats with higher risk. Here's the evidence.
Bloating & DigestionEvidence check
In a Swedish trial of 102 people with IBS, about three-quarters of them women, a physiotherapist helped half of them move more for 12 weeks. Their symptom scores fell by 51 points, against 5 points for the group that kept their usual routine. Five years on, symptoms were still better than at the start, and walking was the most common activity. Here is what they did and how to try it.
PeriodsEvidence check
"Go for a walk" is the cramp advice nobody wants on day one. The best evidence says the timing matters: in 12 trials with 854 women, exercising about three times a week through the whole month cut period pain by about a quarter on a 100-point scale. Here is what the trials used, what they couldn't show for women over 25, and when worse cramps after 40 need a check.
PeriodsEvidence check
Guidelines often suggest exercise for PMS, but on weak evidence. A UK review of 15 trials found women assigned to exercise for at least 8 weeks reported fewer PMS symptoms, mood, physical and behavioral, though most trials had a high risk of bias. A 2025 review of 82 studies with over 100,000 women linked low activity with more PMS and period pain. Here is what the research shows and how to start.
