Home allergy tests don’t work well and experts urge caution

Allergy tests identify antibodies, but not whether allergy symptoms may appear

Skin prick tests and blood tests, the two most common allergy tests, both detect the presence of allergen-specific antibodies. But just because the body has those antibodies doesn’t mean that a person is “allergic” to a substance or that they will develop symptoms of an allergy when encountering the substance. Allergists work with families to interpret the results and sometimes combine that data with approaches including exposure challenges—giving someone a tiny bit of the food or substance they may be allergic to—under medical supervision.

Embracing poor hygiene in early life won't stave off allergies

The hygiene hypothesis, first proposed in 1989 by British immunologist David Strachan, suggests that early life exposure to microbes—like those from farm dust or pets—properly trains our immune systems to respond to threats. But sometimes the idea is misinterpreted: It doesn’t mean that poor hygiene—like failing to wash hands–will help ward off allergies; that type of behavior leads to infections and won’t help with allergy prevention.

Amish kids have far fewer allergies than the general population

Only about 7% of Amish children in a northern Indiana community have tested positive for common allergens in routine skin prick tests, whereas half of the general US population tests positive for them. Asthma is also extremely uncommon among the Amish, even when compared with other farming communities. Researchers are interested in exploring if approaches like exposing kids across the general population to Amish farm dust might stave off some allergies.

The science of food allergies

Why do certain substances trigger an immune response while others don't? Listen to researchers explain the science in this five-minute video. Food allergies affect around 8% of children and 2% of adults in the US, and—unlike sensitivity or intolerance—they involve the immune system mistaking certain harmless proteins in foods as dangerous invaders, triggering a rapid and sometimes severe defense response.

Researchers are investigating if nanoparticle treatments could combat allergies

In rodent work, Northwestern University’s Evan Scott (now at the University of Virginia) and his colleagues have been trying to attack allergies with specially designed nanoparticles—miniscule lab-made objects that can penetrate cells. They stud the nanoparticles with a tiny bit of the allergen specific to the allergy (i.e. cashew protein for cashew allergy) and antibodies that shut down allergic response processes.

Most penicillin allergy diagnoses are wrong

A Freakonomics Radio episode investigates why so many people mistakenly believe they’re allergic to penicillin. This widespread misdiagnosis leads to costlier, less effective treatments and contributes to the growing problem of antibiotic resistance.

The promises and perils of using at-home genetic tests for your health

A primer on genetic testing, personalized medicine, and the promise of pharmacogenomics–the use of genetics to predict an individual's response to a drug.

There are two FDA-approved blood tests that may detect early Alzheimer's disease

Yet the tests are only recommended for those who have symptoms of dementia, and are not definitive on their own. False positives are a concern with these new tests, which detect biomarkers that may indicate the presence of brain proteins linked to the disease. This podcast explores the state of research on the disease and concerns about regulators taking jobs at pharmaceutical and biotech companies, which may influence their approach to approvals. It also dives into an investigation about the data underpinning one experimental Alzheimer's drug.

Peanut allergies dropped by 43% after doctors reversed avoidance guidance, but questions remain

The study’s data appear to confirm the policy shift. Still, since the study did not include an examination of infant diet, researchers can’t definitively say that the guideline shift led to dietary changes and thus directly caused the decline.

Hookworm infection, though risky, may help fight certain health conditions

Early clinical trial research suggests that the parasites trigger the production of specific proteins that quiet our immune systems. This keeps the parasites from being killed, but it also quiets the inflammatory response that underpins allergies, type 2 diabetes, celiac disease, and other autoimmune conditions. Researchers still caution that infection with too many hookworms can cause serious medical complications and that this is not a standardized or approved medical treatment.

There's no definitive test for inflammation, or a baseline for what's considered normal

Existing tests can pick up proteins that indicate an immune response—in particular C-reactive protein, which the liver produces when the body's stressed—but that won't tell you why there's inflammation nor if it's chronic or acute inflammation. (Some users may experience a paywall.)

Hookworm infection, though risky, may help fight certain autoimmune conditions by tamping down the immune system's inflammatory response.

Despite privacy risks, scientists are using DNA in the air to assess ecosystem health

While DNA in soil and water samples has long been used for such analyses, airborne DNA is being incorporated into such efforts to monitor individual species abundance, detect invasive species, measure biodiversity, and determine the success of conservation actions. Future work may include detecting attacks from biological weapons.

Supplements are only typically recommended for those with a proven deficiency

Blood tests and other dietary screening tools by clinicians and nutritionists can indicate whether someone is deficient in needed vitamins or minerals, and those results can then lead to a personalized care plan that may include supplements. Supplements can negatively interact with certain medications, so it's important to speak with your doctor about supplements before taking them.

Most flu cases are treated at home, but antivirals help high-risk patients

Rest, fluids and common medicines usually ease influenza symptoms. For people at higher risk of complications, doctors may prescribe antiviral drugs, which work best when started soon after symptoms begin.

Efforts to create disease-sniffing capabilities for phones still can't match dogs

In this video, a scientist explains why dogs remain leaders in olfactory capabilities, outpacing technology. Scientists have attempted to create artificial "e-noses" for phones to detect early signs of disease, but so far they have not been successful.

Most things you would get tested for at the doctor’s office are influenced by circadian rhythm

In this video, a Salk Institute Researcher offers daily habit tips focused on aligning with your circadian rhythms. She notes heart rate and blood pressure are highest in the afternoon, for example, and there’s a triglyceride peak in the morning. Generally, she says, it’s a good idea to schedule your doctor’s checkups at the same time of day each year so there’s consistency across your data.

This decongestant doesn't work, so why is it still for sale?

Over-the-counter decongestants powered by phenylephrine won't help those with stuffy sinuses find relief, according to current evidence. This 10-minute video explores why these useless medications are still for sale in the US. The decongestant...

Research shows that, on average, humans correctly spot liars about half of the time

Polygraph tests, also known as lie detectors, are better at detecting lies than people, but they still aren't allowed in most courtrooms. That's in part because of mixed signals. For example, spikes in heart rate can be explained by the stress a person feels during interrogation rather than by their own deception. As a result, polygraph tests are prone to false accusations. Results are also unreliable when participants actually believe their lies, examiners have biases, and tricks are employed to help test-takers relax.

Wichita is the worst US city to live in if you suffer from seasonal allergies

More than 100 million people in the United States suffer from allergies each year. But Wichita, Kansas, tops the charts year after year as the worst city in America for those suffering from seasonal allergies. Longer and more intense pollen allergy seasons, however, are increasing the burden of living with seasonal allergies in numerous locations across the country.

Probiotics, which are living bacteria and yeasts, are not recommended for most patients

The American Gastroenterological Association in 2020 concluded that although almost 4 million American adults have taken some form of probiotics, health claims about them are not backed in strong evidence. They only recommend their use for a few specific situations: to prevent Clostridioides difficile infection in people taking antibiotics that kill gut bacteria, to prevent necrotizing enterocolitis in preterm infants, and for the management of a complication of inflammatory bowel disease called pouchitis.

In recent years a child anxiety expert has created and tested a novel phobia and anxiety treatment approach for children, focused on changing how parents respond to the fears.

Testing five common beliefs about bedbugs

Bedbugs are one of the most stigmatized pest infestations due to their resilience and tendency to dwell where humans are most unconscious for long periods of time: beds. A bedbug problem can lead to horror stories and intensive interventions to...

HSAs are frequently criticized for exacerbating inequality in healthcare access

Health savings accounts offer large tax advantages, but require personal contributions. Some argue that the tax advantages benefit wealthy individuals more than anyone else and that HSAs don't do much to help people who can't afford to regularly contribute to one. As a result, HSAs only decrease costs for those who can comfortably invest in them, and health inequalities between high-income and low-income individuals are exacerbated.

Experts argue some frugal habits—like driving farther for cheaper gas—aren't worth it

Other frugal habits experts suggest might not be worth the squeeze include driving to multiple stores in one trip to hunt for deals, as well as buying everything in bulk.

Q-tips can cause more problems than they solve

Swabbing the ear with a Q-tip can disrupt the ear wax that naturally protects the ear from dirt and bacteria. It can also tear the delicate skin of the ear drum, causing permanent hearing loss and constant discomfort that's similar to the symptoms of swimmer's ear. (Some users may encounter a paywall.)

Black mold isn’t more worrisome than other colors of mold

Black mold typically refers to Stachybotrys chartarum, a mold that commonly appears in damp or water-damaged areas of the home. Black mold—and other molds—won’t typically make otherwise healthy people ill, and all molds should be treated the same with respect to health risks and removal. If you have mold allergies, mold can cause an allergic response, and it can trigger asthma attacks for people with asthma. If you have a compromised immune system, then black mold exposure can also cause a fungal infection in your airways or elsewhere in the body.

Urushiol, the oily toxin in poison ivy, can remain allergenic on clothing for years.

Telehealth demand for GLP-1s for weight loss is booming as consumers seek easier access.

Human-to-human transmission of hantavirus remains extremely rare, so the 2026 hantavirus cruise ship outbreak doesn't mean we're facing a COVID-style pandemic risk.

Studies suggest when you sleep is as important as how much you get, and syncing with your circadian rhythms may lead to less fatigue and improved long-term health outcomes

At the beginning of the 20th century, a group of young men ate standard American food—replete with food additives like borax and formaldehyde—as part of government research to better understand food safety.

Fear or disgust related to clusters of holes and cracks, called trypophobia, may stem from evolutionary processes to help us avoid pathogens.

Indefinite cloning of some endangered species may not sustain their longevity because cloning success rates decrease as genetic mutations accumulate.

Listen to an in-depth conversation on the links between Parkinson's disease and herbicide exposure and the challenging pace of scientific investigation.

How the most famous Ebola book, The Hot Zone, which sold 3.5 million copies and was translated into 30 languages, got aspects of the disease so wrong.

When you complete a CAPTCHA on a website to prove you are human, you may be unknowingly training algorithms for self-driving cars, whose systems require training data to help identify crosswalks, bicycles, and other outdoor objects.

See images of medical cases of firework injuries shared on this 'Instagram for doctors.' (Warning: Graphic content)

20,000 letters to the advice columnist 'Dear Abby' provide insight into prevailing sex, religion, and LGBTQ fears, anxieties, and concerns from the 1950s onward.

US housing costs have risen by roughly 175% between 1991 and 2026—but a growing number of Gen Zers are becoming homeowners anyway. In 2025, 4% of homebuyers were Gen Z, up from 3% the year before.

Massive 3D printers have been used to build homes by stacking layers of 'concrete toothpaste,' a fire-resistant material that effectively insulates against outside noise.

Chaos theory—informally known as the butterfly effect—is the reason why weather forecasts are presented with probabilities rather than certainties.

Recent research found that the brain doesn't seem to massively rewire following amputation—upending earlier beliefs about the cause of phantom limb pain.

Scientists can determine Earth's past climate conditions by analyzing air trapped in microscopic bubbles within ice cores—columns of compressed snow layers that build up over hundreds of thousands of years.

To reduce wrinkles in clothing, research recommends gentle wash cycles with more water and tumble drying with smaller loads and longer times.

In its famous catalog, Sears sold $600 DIY house kits from 1908 through the 1940s, resulting in an estimated 100,000 'Sears and Roebuck homes.'

Hedge funds, the private investment firms that trade a wide swath of financial assets, make money by imposing steep fees on investors and from the fund's investment performance.

Sunflowers have long been a symbol of nuclear disarmament because they can extract large amounts of radioactive cesium from soil.

Pure water does not conduct electricity because this flow of energy requires the movement of charged particles, and water is a neutral molecule.

Explore an interactive map built from more than 100,000 survey responses on where people find joy in their lives