Why Do My Fingernails Smell Like Onions? 

If you usually cook with onions, then you are likely not a stranger to how lasting the smell can be on your hands and indeed any surface the onion juice comes in contact with.

Truly, onion has a stubborn and pungent odor that is easily noticeable. However, it is time to seek answers when you find your fingernails oozing with oniony flavors even without having touched onions or days after you’ve scrubbed the onion juice off your hands.

Why do my fingernails smell like onions?

The reason why your fingernails smell like onions could be due to natural keratin in the nails, a bacteria infestation, a medical condition such as celiac disease, medication, and supplements, emotional stress, hypersensitivity to smells, or onion molecules still caught under the nails.

Let’s look at these possible reasons one after the other.

7 Reasons Why Fingernails Smell Like Onions

1. Natural Keratin in the Nails

Keratin is a type of protein that is found in the hair, nails, and skin of humans. It is also found in the scales, horns, feathers, hooves, and claws of other animals that have backbones. This protein helps to protect these organs from tears and scratches, thereby keeping them healthy.

Where it gets interesting is that this protective substance contains sulfur compounds. Guess what? That smell in your nails that reminds you of onions is the smell of sulfur in keratin.

Yes, sulfur molecules are present in onions, rotten eggs, garlic, and other alliums that have that distinct sulphuric stench.

You can easily tell if it’s keratin that is behind the whiff in your fingernails. This is because it will only smell as you’re cutting it or immediately after trimming. It’s almost like how you get the scent of freshly cut grass. If, however, the odor continues long after your nail trimming, you may be dealing with bacteria.

2. Bacteria Infestation

Another possible reason for onion-scented nails is a build-up of bacteria that produces sulfur under the nails.

These bacteria, specifically called staphylococcus hominis usually break sweat down to produce thioalcohol which contains some amount of sulfur.

Hence, having a colony of Staphylococcus hominis underneath or around your nails can make them emit the notorious smell of sulfur.

These bacteria are not only responsible for foul-smelling fingernails. They are also behind a body odor and certain foul smells in various parts of the body, including the armpit, mouth, hands, and vagina!

I used to wake up to a strong taste of onion on my breath. I had concluded that it must be from previously eaten onions (I love eating raw onions!) until I researched and found out that it was bacteria having a field day in my mouth. The horror!

If any of the above isn’t what is causing your fingernails to smell, then you need to consider some health and body conditions.

3. Celiac Disease

Celiac disease is an abnormal immune system reaction to a protein called gluten. This protein is present in foods like rye, barley, wheat, and malt.

Over time, the immune system’s inflaming response to gluten will harm the lining of the small intestine, making it unable to absorb some nutrients. This leads to foul smells on the person suffering from celiac disease.

4. Medication and Supplements

Some medications and food supplements contain sulfur, which can diffuse through the skin to give off its distinct odor. Onions, garlic, and leeks are natural foods that also have sulfur molecules in them. When eaten in large quantities, their fragrance can leak out of your pores.

5. Emotional Stress

The Mayo Clinic says that a person suffering from emotional stress or anxiety produces oily sweat richly conducive to sulfur-making bacteria. This is clearly observed in people who usually develop clammy and sweaty palms when anxious or emotionally distressed.

Allowing the sweat to stay can attract and nurture bacteria that produce the by-product that gives your entire hands, and fingernails, a whiff of sulfur.

6. Hypersensitivity to Smells

Are you pregnant? Do you suffer from fibromyalgia? No wonder you perceive onions in unexpected places!

During pregnancy, hormones (estrogen) are on a roll, and certain senses tend to get heightened. The smell is one such sense.

Pregnancy can cause you to be hypersensitive to smells such that the very faint lingering of onion oil on your nails may seem like an overpowering stench.

You could even perceive the onion scent carried by the air from your neighbor’s apartment to yours. Weird, isn’t it? Good thing you won’t be pregnant forever.

Fibromyalgia also activates the senses and can send your sense of smell into overdrive, catching wind of things that passed through and are long gone.

It is a condition that leads to so much weakness and pain, and a heightened sense of smell is actually one of its symptoms. This results from the pain that drains so much of the patient’s energy, causing over-sensitivity to every other stimulus.

7. Onion Molecules Still Caught Under the Nails

Finally, that smell may be nothing more than what it appears to be: onion. As I stated at the beginning, onion juice is very stubborn, and its odor can refuse to leave even when you try to send it packing with loads of soap and running water.

Regular soap does not have what it takes to neutralize the acid produced when cutting an onion open, the same acid that makes you cry when cutting onions.

Hence, the onion flavor can cling to your skin and the underside of your fingernails for up to two days after you cut onions and wash your hands.

Possible Types of Smell From Fingernails

Apart from smelling like onions, there are other kinds of smells that people have reported concerning their fingernails.

Ordinarily, fingernails should be free of any smell except the one that may be produced by the keratin in nails when cut. And keratin odor usually lasts only a short while.

However, fingernails have been known to emit a garlic-like smell and that of rotten eggs too. This is also due to the sulphuric scent of keratin or the sulfur molecules cooked up by certain bacteria.

Another commonly experienced smell is that of metal. Yes, people have been known to exude a metallic aura. This is due to contact between the skin and metallic substances that cause a particular kind of oil in the skin to break down.

Other alarming smells are cheese, vomit, or poop. These most likely signal a fungal infection called onychomycosis.

This is a nail fungus, and though it is more liable to infect toenails, it is also possible to experience onychomycosis in the fingernails.

Apart from the stench it can cause, it can also give the fingernails a dark or greenish color. Nail fungus can as well make the nails thick and crumbly.

How To Remove Onion Smell From Your Fingernails

Having discovered why your fingernails have that peculiar fragrance of onions, you probably want to eliminate the smell, no matter how much you love the actual onions. No one wants to go around smelling like a giant onion root.

Find options on how to get rid of the onion smell from your fingernails below.

1. Using Stainless Steel

Sulfur molecules usually bind themselves to stainless steel molecules. Therefore, stainless steel helps to remove the source of the odor itself from your nails.

Just rub the affected fingers with a spoon or stainless steel while holding them under cold water. Try to reach underneath the fingernails as much as possible to get rid of the odor.

2. Using Lemon Juice

Lemon juice is strong enough to neutralize sulphuric acid. Drop some of the juice around and under your fingernails, and watch it do its magic.

Be careful, though, it is also strong enough to lead to irritation. Also, the juice stings if pre-existing cuts on your hands or if the hands are dry. Afterward, wash your hands with cold water.

3. Using Salt

Wet your hands and rub some salt all over them. If you prefer, you can also mix salt and lemon juice. Rinse off after a few seconds of massaging.

4. Using Baking Soda

Make a little paste using one salt, two baking soda, and a little water. You can mix this on your hand or in a small bowl.

Rub against your fingernails and underneath for a few seconds, then rinse off. The baking soda absorbs the smell, and the salt helps to remove dead skin (exfoliation), leaving your hands and fingernails smelling nice and feeling smooth.

How To Prevent Your Nails From Smelling Like Onions

  1. After handling onions or garlic, get the clingy juice off your hands at once by using one of the above methods.
  2. Use gloves to prevent the juice from getting on your hands in the first place.
  3. Maintain proper hygiene of the hands and fingernails.
  4. If possible, avoid medication and supplements that contain sulfur. Also, avoid eating too much garlic, leeks, or onions.
  5.  Practice stress management techniques or see a specialist for anxiety disorders.

Care Of The Fingernails

To avoid abnormalities like the onion smell in the fingernails, it is important to take good care of them. Follow the tips below for grooming healthy and attractive nails.

  • As you apply lotion to your hands, let the nails also benefit by massaging the moisturizer.
  • Soak fingernails in warm water just before cutting them, or take a warm shower. This softens the nails, making it easier for you to trim them.
  • Use clippers or nail scissors for trimming fingernails. First, trim straight across the nails, then file the corners down in a nice curve.
  • Avoid cuticle removal as the cuticles help to protect your nail roots.
  • Use nail hardener more but less nail polish remover.
  • Infuse biotin into your diet.
  • Only visit certified salons for your manicures.
  • Finally, consult a doctor immediately if you observe anything abnormal about your nails. It could be a symptom of something else going on in the body.

What is smelling onions a symptom of?

Smelling onions can be a symptom of certain medical conditions, such as diabetes, kidney failure, or liver failure, or it can be a side effect of certain medications. If you have been smelling onions and are concerned, it is a good idea to consult a healthcare professional for further evaluation.


Your fingernails may smell like onions due to the natural keratin in the nails, a bacteria infestation, celiac disease, some medication and supplements, emotional stress, hypersensitivity to smells, or onion molecules still caught under the nails.

However, there are remedies for the odor. Nail hygiene is also key in preventing any stench from your fingernails. Keep clean.


1. 4 Reasons Your Fingernails Smell, and What to Do About It


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