You can test your sense of taste at home with a few simple experiments using items from your kitchen. The key is separating true taste (sweet, sour, salty, bitter, and savory) from flavor, which depends heavily on your sense of smell. Many people who think they’ve lost taste have actually lost smell, and a couple of quick tests can help you figure out which one is affected.
The Jelly Bean Test: Taste vs. Smell
Most of what people call “taste” is actually flavor, and flavor depends on your nose more than your tongue. Before testing taste itself, it helps to figure out whether smell is the real problem. The jelly bean test, developed by the National Institutes of Health, is the simplest way to do this.
Have someone hand you a jelly bean while you’re blindfolded. Eat it and try to identify the flavor. Then pinch your nostrils shut, eat a second jelly bean, and try again. With your nose open, you should be able to tell apple from cherry from lemon. With your nose pinched, most people can only detect broad categories: sweet, sour, or bitter. If your experience is the same whether your nose is open or closed, your smell is likely the issue. If you can’t even detect sweetness or sourness with your nose pinched, that points to an actual taste problem.
You can run a similar test with any strongly flavored food. Try eating a piece of chocolate or a slice of orange first normally, then with your nostrils pinched. The difference tells you how much your smell is contributing.
Testing the Five Basic Tastes at Home
Your tongue detects five distinct tastes: sweet, salty, sour, bitter, and umami (savory). You can test each one individually with common pantry items dissolved in small amounts of water.
- Sweet: dissolve a teaspoon of sugar in a cup of water
- Salty: dissolve half a teaspoon of salt in a cup of water
- Sour: squeeze a few drops of lemon juice into a cup of water
- Bitter: brew a strong cup of black coffee or use tonic water
- Umami: dissolve a pinch of MSG or soy sauce in water
Take a sip of each solution, swish it around your mouth, and spit it out. Rinse with plain water between each one. You’re checking two things: whether you can detect that something is in the water at all (detection), and whether you can correctly name what taste it is (recognition). If you can detect a taste but can’t tell sweet from salty, that’s a partial loss called hypogeusia. If you can’t detect anything at all across multiple tastes, that’s closer to ageusia, a complete loss of taste.
To make this more reliable, have someone prepare three cups for each taste: one with the solution and two with plain water. Try to pick which cup has the taste in it. This mirrors a clinical method called the three-drop test, where patients must correctly identify the taste-containing sample three times before the result counts. If you can’t, the concentration is increased until you either detect it or it’s clear there’s a deficit.
Testing Different Regions of Your Tongue
Taste loss sometimes affects only one area of the mouth, particularly when a specific nerve is damaged. The front two-thirds of your tongue is supplied by one nerve, and the back third by another. You can do a rough regional test at home using a cotton swab.
Dip a cotton swab in one of your test solutions (salt water works well) and dab it on the tip of your tongue, then the sides, then as far back as you can comfortably reach. Compare what you feel in each area. If one side is noticeably weaker than the other, or the front and back give very different results, that’s useful information to bring to a doctor. In clinical settings, professionals use paper strips soaked in sweet, sour, salty, and bitter solutions at four different concentrations, placed on specific tongue regions while the tongue is sticking out. A score below a certain threshold, or a noticeable difference between the left and right sides, flags a problem worth investigating.
What Doctors Use for a Definitive Diagnosis
If your home tests suggest something is off, clinical testing can pinpoint exactly what’s happening. The most common professional methods include taste strips (paper strips impregnated with different flavors at increasing concentrations), taste tablets that work on the same principle but are easier to store and use in a clinic, and electrogustometry.
Electrogustometry uses a small electrical current applied to different areas of the tongue. The current stimulates taste nerves directly, producing a metallic, sour sensation. By adjusting the current between 1.5 and 400 microamps, the test can map exactly where your taste detection is working and where it isn’t. It can’t distinguish between different taste qualities since the electrical stimulation always produces the same metallic flavor, but it’s excellent for localizing damage to a specific nerve or region.
Common Causes of Taste Loss
The most frequent cause of sudden taste loss is a viral infection. During COVID-19, taste and smell loss typically appeared about 4 to 5 days after other symptoms and lasted 7 to 14 days on average. Most people recovered within 3 weeks, with significant improvement in the first two weeks. Other respiratory viruses, sinus infections, and even severe colds can temporarily knock out taste through similar mechanisms.
Medications are another major culprit, and the list is longer than most people realize. Blood pressure medications, antibiotics, antidepressants, anti-seizure drugs, thyroid medications, antihistamines, and chemotherapy agents can all alter taste. Some drugs cause taste disturbance in a large percentage of users: the glaucoma drug acetazolamide affects taste in 12 to 100 percent of patients depending on the study, while the chemotherapy drug cisplatin causes it in 77 percent. Even common medications like the blood pressure drug captopril affect taste in 2 to 7 percent of users, and the antifungal terbinafine does so in about 3 percent. If your taste loss started around the time you began a new medication, that connection is worth exploring.
Zinc deficiency is a less obvious but well-established cause. Zinc is essential for producing gustin, a protein in your saliva that supports the growth and maintenance of taste buds. When zinc levels drop, gustin production falls and taste buds don’t develop normally. Blood zinc levels below about 60 to 69 micrograms per deciliter are considered deficient and associated with taste problems.
Signs That Point to Something Neurological
Most taste loss is temporary and tied to infections, medications, or nutritional deficits. But certain patterns suggest nerve damage or a neurological cause. Taste loss on only one side of the tongue can indicate damage to the nerve serving that region, sometimes from dental procedures, ear surgery, or Bell’s palsy. Taste loss combined with facial numbness, weakness, or difficulty swallowing raises more concern.
Brief episodes of distorted taste lasting under two minutes can sometimes represent seizure activity originating in the brain’s temporal lobe. These are distinct from the longer-lasting taste distortions (five minutes to hours) that come from problems with the taste or smell organs themselves. Taste changes that come and go in very short bursts, especially paired with other unusual sensations, warrant a neurological evaluation.
The Blue Dye Papillae Count
This test doesn’t measure whether you’ve lost taste, but it can tell you something about your baseline taste hardware. Dab blue food coloring on the tip of your tongue with a cotton swab. The small bumps that contain taste buds (fungiform papillae) resist the dye and stay pink, while the surrounding tissue turns blue. Place a hole-punch reinforcement sticker on your tongue tip and count the pink bumps inside the circle using a magnifying mirror and flashlight.
People with more fungiform papillae per square centimeter tend to have more intense taste perception. This is more of a sensitivity test than a loss test, but if you’re wondering whether you’ve always been a less sensitive taster versus having developed a new problem, it provides some context. A very low count suggests you may have always had reduced taste intensity, while a normal or high count combined with poor performance on the taste solutions above points more clearly toward an acquired loss.