Some degree of genital odor is completely normal. Your groin is warm, enclosed, and packed with sweat glands and bacteria, all of which contribute to a natural scent that shifts throughout the day. A mild, musky smell is typical and not a sign of poor hygiene or illness. But if the smell has changed noticeably, become stronger, or taken on a fishy or foul quality, something specific is usually driving it.
Why Genitals Have a Natural Scent
Your groin is home to apocrine sweat glands, a type of sweat gland that develops during puberty in hairy areas like the armpits, scalp, and genitals. These glands secrete an oily fluid made of proteins, lipids, and steroids. The fluid itself is nearly odorless. The smell comes from bacteria on your skin breaking down those secretions into volatile compounds, including fatty acids and sulfur-containing molecules. Bacteria from the Corynebacterium and Staphylococcus families are among the biggest contributors.
For people with vaginas, there’s an additional layer. The vagina maintains its own ecosystem of bacteria, dominated by Lactobacillus species that produce lactic acid and hydrogen peroxide. This keeps vaginal pH slightly acidic, in the range of 3.8 to 4.2. That acidic environment creates a faint tangy or slightly sour scent, which is healthy and expected. The smell can fluctuate with your menstrual cycle, sexual activity, and even the time of day.
Sweat, Clothing, and Everyday Causes
The most common reason for stronger-than-usual genital odor is simply sweat and friction. Tight clothing, synthetic underwear, and extended periods of sitting trap heat and moisture against the skin, giving bacteria more to work with. Exercise, hot weather, and stress all increase apocrine gland activity. Because the groin stays warm and enclosed, odor builds up faster there than on other parts of the body.
Switching to breathable cotton underwear, changing out of sweaty clothes promptly, and washing the external genital area with warm water (no internal washing for vaginas) can make a significant difference. Harsh soaps, scented washes, and douches tend to make things worse by disrupting the skin or vaginal microbiome.
Foods That Change How You Smell
What you eat can directly affect genital odor. When your body digests certain foods, it releases compounds through your sweat glands, and bacteria on your skin amplify those scents. The groin and armpits are where this shows up most.
- Garlic and onions release sulfur compounds that mix with apocrine sweat and intensify odor on the skin’s surface.
- Spices like curry, cumin, and fenugreek contain volatile compounds that are absorbed into the bloodstream and released through sweat.
- Red meat releases odorless proteins through perspiration that become pungent when skin bacteria break them down.
- Cruciferous vegetables (broccoli, cabbage, Brussels sprouts) release sulfuric compounds intensified by sweat.
- Asparagus is converted into sulfur-containing compounds during digestion, which is why urine can smell strongly after eating it.
- Alcohol is metabolized into acetic acid, which is released through your pores.
These effects are temporary and harmless. They typically resolve within a day or two of eating the food.
Bacterial Vaginosis: The Most Common Infection-Related Cause
If you have a vagina and the smell is distinctly fishy, bacterial vaginosis (BV) is the most likely explanation. BV happens when the balance of vaginal bacteria shifts away from protective Lactobacillus species toward other types of bacteria. These bacteria produce compounds called cadaverine and putrescine, which are directly responsible for the characteristic fishy odor. Those same compounds also suppress the growth of healthy vaginal bacteria, which can make the imbalance worse over time.
BV doesn’t always cause obvious symptoms, but common signs include off-white, grey, or greenish discharge along with a fishy smell that often gets stronger after sex or during your period. It’s not a sexually transmitted infection, though sexual activity can trigger it. BV is treated with a short course of antibiotics, typically taken for five to seven days either orally or as a vaginal gel or cream. It clears up quickly with treatment but has a tendency to recur.
Trichomoniasis and Other Infections
Trichomoniasis is a common sexually transmitted infection caused by a parasite. It can produce a fishy-smelling discharge that ranges from clear to white, yellowish, or greenish. The discharge is often thin or noticeably increased in volume. Many people with trichomoniasis also experience itching, burning, or discomfort during urination or sex, though some have no symptoms at all. It’s easily treated once diagnosed.
Yeast infections, by contrast, don’t typically cause a strong odor. The hallmark of a yeast infection is thick, white, cottage cheese-like discharge with itching and irritation. If odor is your primary concern, yeast is less likely to be the cause.
Penile Odor and Smegma
For people with penises, the most common cause of noticeable odor is inadequate cleaning beneath the foreskin. A white, cheese-like substance called smegma can build up under the foreskin when dead skin cells and natural oils accumulate. This creates an environment where bacteria thrive, producing a strong smell.
If the area also becomes red, swollen, itchy, or painful, that may be balanitis, an inflammation of the head of the penis. Balanitis is most often caused by not regularly cleaning under the foreskin, though it can also result from infections or skin irritation. Other signs include discolored patches on the skin, shiny or white areas, and burning during urination. Gentle daily cleaning with warm water usually prevents smegma buildup. If irritation or swelling develops, treatment depends on the underlying cause but often involves a short course of topical medication.
Hormonal Changes and Life Stages
Estrogen plays a major role in maintaining the vaginal ecosystem. When estrogen levels drop, as they do during menopause, the vaginal pH rises above its usual acidic range. A pH higher than 4.5 becomes common after menopause, and this less acidic environment changes which bacteria flourish, often leading to a noticeable shift in scent. Some people describe it as stronger, more ammonia-like, or simply different from what they’re used to.
Hormonal shifts during pregnancy, breastfeeding, and certain phases of the menstrual cycle can cause similar, temporary changes. These are not signs of infection on their own, but if the odor is accompanied by unusual discharge, itching, or irritation, it’s worth getting checked.
Forgotten Tampons and Foreign Objects
A sudden, intensely foul smell is one of the clearest signs of a retained tampon or other foreign object in the vagina. This is more common than people realize, and the odor is usually unmistakable: much stronger than anything caused by normal bacterial shifts. Other warning signs include unusual discharge, pelvic pain, and fever. If you suspect a retained tampon, it needs to be removed as soon as possible. You can sometimes reach it yourself, but if you can’t, a healthcare provider can remove it quickly in an office visit.
What a Normal Smell Looks Like
A healthy genital area has a mild scent that varies from person to person. For vaginas, slightly sweet, tangy, or mildly musky are all within the normal range. The smell may shift after exercise, sex, or at different points in your cycle. For penises, a faint musky smell after a long day is expected.
The smells that warrant attention are those that are new, persistent, and accompanied by other symptoms: fishy or rotten odors, unusual discharge (in color, texture, or amount), itching, burning, pain, or swelling. A change in smell alone, without other symptoms, is often driven by sweat, diet, or hormonal shifts and resolves on its own or with basic hygiene adjustments.