Why Does My Vagina Smell Like Onions?
Why Does My Vagina Smell Like Onions?
If you’ve ever pulled down your underwear and thought, “Why does it smell like onions down there?”, you are not alone and you’re also not gross. A mild onion‑like smell is usually about sweat, skin, and food, not dirtiness or “bad hygiene.” But sometimes, a strong onion odor can signal an infection or a forgotten tampon that needs attention. [healthline]
This guide breaks down the most common reasons for onion‑like vaginal odor, what’s normal, what isn’t, and how to know when it’s time to see a clinician.
Normal Reasons for an Onion‑Like Smell
Sweat and skin folds
Your vulva (the outside) has sweat glands just like your armpits. When sweat mixes with bacteria on the skin and tiny bits of urine or discharge, it can smell a lot like onions or strong body odor. [intimaterose]
Things that make this more noticeable:
Hot days, workouts, or long shifts on your feet.
Tight leggings or synthetic underwear that trap moisture.
Not changing out of damp underwear after sweating.
If the smell is stronger after exercise or a long day and fades after a shower and clean underwear, sweat is the most likely reason. [cleavelandclinic]
Food and diet
Onions, garlic, curry, and other sulfur‑rich foods can change how your sweat, urine, and discharge smell. [medicalnewstoday]
What happens:
These foods break down into compounds that leave the body through sweat and urine.
Groin sweat and discharge can pick up the same scent as your breath.
Clues it’s food‑related:
You recently ate a lot of onions/garlic/spicy food.
The smell shows up within a day and fades within 24–48 hours. [healthline]
You don’t have to cut out all flavor; just notice whether certain foods consistently give you that onion vibe.
Hormones and normal discharge changes
Your vaginal discharge and scent naturally change across your cycle:
Around ovulation, discharge increases and can smell stronger.
During pregnancy or on certain birth control, estrogen surges can make odor more noticeable. [axiwah]
As long as the smell is mild, not foul, and not paired with burning, itching, or unusual color, it’s usually part of your normal hormone pattern. [medicalnewstoday]
When Onion Smell Is a Red Flag
A strong or foul onion‑like smell especially when it doesn’t improve with a shower can point to something more than sweat or diet.
Forgotten tampon or object
A forgotten tampon is one of the most common causes of a sudden, intense rotten or onion‑meat smell. [healthline]
Other signs:
Brown, bloody, or gray discharge.
Odor that hits you even through clothes.
Possibly spotting, burning, or feeling “full” in the vagina.
If you think this is possible:
Gently feel inside the vagina with clean fingers for a string or tampon.
If you can’t find or remove it or you feel unwell see a clinician right away. [healthline]
Bacterial overgrowth or infection
The classic fishy smell of bacterial vaginosis is well known, but some women describe early or mild BV, or other bacterial overgrowth, as “oniony” or sour” rather than purely fishy. [lewisvillewomenscare]
Possible signs it’s more than sweat or diet:
New or stronger smell that lasts more than a few days.
Change in discharge (thinner, grayish, yellow, or green).
Itching, burning, redness, or pain with sex or peeing. [intimaterose]
Some STIs like trichomoniasis or chlamydia, can also cause a strong, foul, sometimes onion‑like odor, often with yellow‑green discharge and irritation. [verywellhealth]
If you have odor plus symptoms, especially with a new partner, get tested for BV, yeast, and STIs.
Rare but important causes
Very rarely, an onion‑like or foul odor can come from:
A rectovaginal fistula (abnormal connection between rectum and vagina) causing gas or stool to pass through the vagina. [better2know]
Cervical or vaginal cancer, usually with bleeding, pelvic pain, and persistent abnormal discharge.
These are uncommon, but if you notice odor plus bleeding between periods, pain, or stool/gas from the vagina, you need prompt evaluation.
Quick Self‑Check: Normal vs Not
You’re likely in the normal/benign zone if:
The smell is mild, comes and goes, and is clearly linked to sweat, a long day, or recent onion/garlic‑heavy meals.
It improves with a shower, clean cotton underwear, and air‑flowy clothes.
There’s no itching, burning, pain, or new discharge [healthline]
You should book an appointment if:
The smell is strong, sour, or rotten and lasts more than 3–4 days.
You also have itching, burning, pelvic pain, or unusual discharge.
You think a tampon or object might still be in.
You’ve had unprotected sex with a new partner and notice a new odor. [verywellhealth]
What Actually Helps (Without Making Things Worse)
Support your natural balance
Wash the vulva (outside only) with warm water or a very gentle, unscented cleanser. Skip internal washing and douches these strip protective bacteria and can cause BV, which makes odor worse. [healthline]
Change underwear daily, and more often if sweaty. Cotton or moisture‑wicking fabrics are best. [kushae]
After workouts, rinse off or at least change out of damp leggings as soon as you can.
Adjust diet and hydration
If you notice a consistent pattern:
Cut back a bit on onions, garlic, strong spices, and very processed foods for a week and see if the scent changes. [healthline]
Drink plenty of water diluted urine and sweat tend to smell less intense.
You don’t need a restrictive “vaginal detox diet.” Just notice which foods your body broadcasts the loudest.
Avoid common “fixes” that backfire
Skip:
Vinegar or lemon douches (acidic burns and disrupts your microbiome).
Perfumed sprays, wipes, and scented pads (irritation + higher infection risk).
Putting yogurt, garlic, or essential oils inside the vagina. [medicalnewstoday]
These can create or worsen infections and make you more self‑conscious about odor long‑term.
When to See a Clinician (and What to Ask For)
Make an appointment if:
Onion‑like or foul odor persists more than a few days despite showering and clothing changes.
You notice new discharge, itching, burning, or pelvic pain.
You suspect a retained tampon, especially with fever or feeling sick.
You’ve had unprotected sex and are worried about STIs. [verywellhealth]
Ask for:
A full vaginal exam and swabs for BV, yeast, and STIs (including trichomoniasis and chlamydia when appropriate). [better2know]
Help reviewing medications, hormones, and hygiene products that might be affecting your odor.
Clear instructions on what’s normal for you vs what should trigger another visit.
Key Takeaways
A mild onion‑like scent often comes from sweat and diet mixing with normal discharge, especially after hot days or onion/garlic‑heavy meals. [intimaterose]
A strong, persistent, or foul onion smell, especially with discharge, itching, or pain, can signal issues like BV, STIs, or a forgotten tampon, and deserves a proper check‑up.
Gentle external washing, breathable underwear, food awareness, and skipping harsh “feminine hygiene” products usually do more for vaginal odor than any detox or DIY remedy. [cleavelandclinic]
Your vagina isn’t supposed to smell like a scented candle. It’s allowed to have a real‑life body scent. Your goal is to learn what’s normal for you and when something shifts enough that it’s worth getting checked.
Frequently Asked Questions
Can an STI make my vagina smell like onions?
Yes. Some STIs especially trichomoniasis and, less often, chlamydia or gonorrhea can cause strong, foul, sometimes onion‑like or rotten odors along with yellow‑green discharge, burning, or pelvic pain. Any new strong smell with symptoms or a new partner is a reason to get tested.
How long should I wait before seeing a doctor about odor?
If the onion‑like smell is mild, clearly linked to sweat or recent food, and goes away within 1–2 days after showering and changing clothes, you can just keep an eye on it. If it’s strong, lasts more than 3–4 days, or comes with discharge, itching, burning, or pelvic pain, schedule a visit.
Will changing my diet really change how I smell?
Often, yes. Strong‑smelling foods like onions, garlic, and some spices can temporarily affect how your sweat, urine, and discharge smell, especially in warm, sweaty areas like the groin. You don’t need a strict diet just notice whether cutting back on those foods for a week softens the scent.
