Stress is a response to external triggers, while anxiety is persistent and internal

How do anxiety and stress differ?

This article explains that though “stress” and “anxiety” are often used interchangeably, there are distinct differences between the two. Stress is defined as the body's response to an external trigger and can be classified as acute or chronic. Anxiety, however, tends to be triggered internally by excessive thoughts and judgement. Whereas stress disappears when the trigger is gone, anxiety tends to stick around. If left unchecked, both can escalate into more severe mental health conditions.

Stress evolved as a survival mechanism to keep humans alive

Stress activates the “fight-or-flight” response when we face threats. It’s triggered by the hypothalamus, which signals the release of adrenaline and cortisol, heightening awareness and energy. While acute stress helps in short bursts, chronic stress—persistent over time—can harm both physical and mental health, leading to conditions like hypertension, anxiety, or depression.

Stress can be contagious—and scientists want to learn more about it

Researchers have shown that being around someone who is stressed can trigger a stress response in your body, such as elevated cortisol levels and elevated heart rate. One way this was recently studied was by having people watch stressful activities, like a recorded job interview or solving challenging math problems, and then sampling hormones in observers' spit.

The two phases of stress: fast and slow

The physiological response to acute stress generally involves two phases—the "fast" response in which adrenaline is released, and a second "slow" response in which cortisol is released. This technical resource reviews what happens in the body during each phase.

Stress affects different animals in different, but useful, ways

Animals feel stress when they experience actual dangers—such as a zebra chased by a lion. Humans often feel stress from worries, memories, or even thoughts about problems that may occur in the future. For this reason, animals tend to experience stress in short, intense bursts. Conversely, people can feel stressed for long periods, which can eventually be harmful to their health.

The positives of feeling stressed

Worrying about past events and upcoming challenges is not a pleasant experience, but a reasonable amount of stress can bring a lot of good into our lives. In this episode of "The Happiness Lab" with Dr. Laurie Santos, two psychology experts offer tips for resetting one's relationship with stress. Listen and learn how to make stress a positive tool rather than a debilitating emotion.

Fearology, or the study of fear, explores the difference between stress and fear

Our brains involuntarily respond to our environment and signal alarm when that isn’t always needed, triggering responses that include goose bumps. But understanding fear and how to talk our brains into calming down can improve daily life.

Consuming true crime media can increase stress and anxiety

Consuming true crime media can activate one's sympathetic nervous system, which controls the fight-or-flight response. Staying in this heightened state of vigilance can lead to stress-related illnesses, including hypertension, and mental conditions, including depression and anxiety. Additionally, people who actively consume crime news, whether they consider it to be entertainment or educational in nature, report being more fearful of crime, regardless of actual crime rates.

A framework for the various potential causes of insomnia

Insomnia typically occurs in people dealing with life stressors and physical or mental health conditions, though the exact cause continues to elude researchers. Generally, the factors can be broken down into external (such as stress, medication, etc.) or internal (neurological) factors.

Menopause can exacerbate anxiety

Some research shows that menopause can fuel anxiety and also that pre-existing anxiety can boost the chances of experiencing other menopause symptoms, including hot flashes, insomnia, and brain fog. But treatments including hormone replacement therapy, breathing exercises, and other forms of exercise can alleviate some of these symptoms.

PTSD is a long-lasting mental disorder linked to past traumatic events

Posttraumatic stress disorder is a mental health condition arising from traumatic events with four key symptoms: intrusive memories, avoidance behavior, negative moods and thoughts, and changes in emotional and physical reactions.

Panic attacks are intense fear episodes that often occur without a clear trigger

Unlike typical fear responses to real danger, panic attacks can mimic serious health problems, such as heart attacks. Sweating during a panic attack may seem random, but it's a leftover survival mechanism that made it easier for our ancestors to escape by slipping out of an attacker’s grasp.

Nightmares are unpredictable, but are linked to stress, anxiety, trauma, and more

Nightmare comes from the terms "night" and "mare," an Old English word for evil, suffocating spirits. Nightmares are parasomnias, meaning they are undesirable events experienced during sleep, and may stem from building tensions in one's unconscious.

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.

The WHO defines burnout as an occupational phenomenon

While it’s not a medical condition, the World Health Organization defines burnout as an occupational phenomenon in the International Classification of Diseases (ICD-11), and considers it separate from general stress.

DNA damage and chemical stress causes cellular aging

While outward signs of aging, like gray hair and wrinkles, are easy to spot, aging changes at the cellular level are less obvious. The decline within cells stems from numerous sources, including DNA damage, oxidative stress, and accumulated waste.

There’s a psychological explanation for ‘FOMO,’ or the fear of missing out

This video breaks down FOMO—what it is, how it works, and why it happens—showing how social comparison and uncertainty trigger anxiety that pushes people toward risk-taking and constant checking behaviors.

Mental health symptoms may manifest differently across cultures

Mental health, like physical health, is imbued with values, beliefs, and traditions. Symptoms of distress are not universal and may differ based on racial, ethnic, and cultural contexts. Because mental health may be stigmatized or communities may have varying belief systems about causes of mental health challenges and how to fix them, it may affect how symptoms manifest. Chest pain, for example, may be a sign of mental distress—not the need for a doctor.

Inflammation appears to cause specific symptoms of depression

A large analysis of existing studies published in 2021 found that systemic inflammation is associated with fatigue, appetite changes, and sleep disruption, rather than some of depression's broader symptoms including hopelessness about the future, or feeling fearful. This may suggest that inflammation influences specific symptoms of the condition, rather than the disease as a whole.

Doctors differentiate between a phobia and fear by asking patients whether their fear interferes with their day-to-day activities.

Watch actress Kristen Bell discuss her challenges with depression and anxiety

Bell describes how depression can make it difficult to celebrate good news, and how decision fatigue can make simple decisions feel Herculean. She reveals how she wishes she'd discussed these struggles publicly earlier in her career.

Autism and ADHD may have overlapping symptoms and someone can have both disorders

This video explores similarities and differences between these two disorders, which both have genetic causes. Challenges with attention, hyperactivity, and impulsivity are typical of ADHD. Fidgeting, problems picking up on social cues, emotional dysregulation, and being oblivious to time may occur with both disorders—though the impetus for these behaviors may differ.

When to see a doctor over memory lapses

Memory includes various, distinct functions, like working memory (storing information temporarily) and procedural memory (your body's ability to perform a task unconsciously). Forgetting a word or losing your keys can feel like red flag memory lapses, but they are, in fact, language or attention problems, not memory ones. However, a lapse on top of stress, lack of sleep, chronic dysfunction, or an injury may be a red flag to see your doctor.

Its predictability distinguishes SAD from other forms of depression

Most major depression is "stochastic"—brought on without a clear trigger. SAD—also known as major depression with a seasonal component—is unique in that its onset is predictable. Many of those affected can predict its occurrence accurately within a range of three weeks. This podcast explores this unusual feature of SAD, among other expert takes.

Are you a digital hoarder? There are four types, actually

Digital hoarding: the phenomenon where people accumulate excessive digital clutter, like thousands of emails, hundreds of open browser tabs, and unused apps on their devices. This behavior has been associated with increased stress levels and potential negative impacts on mental well-being. Are you a digital hoarder? Find out the four types here.

Long-term goose bumps are something to flag to your doctor

Although rarely a cause for concern, persistent goose bumps with no known cause could be a symptom of something to discuss with your doctor, including anxiety, a hair follicle blockage, or conditions that arise from an overreaction of the autonomic nervous system.

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.

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

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

Alzheimer's can lead to brain shrinkage, with an average of around 2% of volume reduction per year

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.

Shooting stars, or meteors, are fragments of asteroids and comets that burn up as they enter Earth's atmosphere, creating streaks in the sky called meteor showers.

Use this calculator to find the dollar value of your mental load, from meal planning to coordinating after-school care for your children.

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

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

How fusion—which releases energy when two lighter atoms combine to form a heavier atom—differs from fission

While the sun's gravity keeps the planets in orbit, their gravity also pulls on the sun, causing it and everything else in the solar system to orbit around a mutual balance point called the barycenter—the true center of the solar system.

US consumers collectively owe more than $1T to credit card companies—almost as much as they owe in auto loans.

The rivalry between Alexander Hamilton and Thomas Jefferson centered on federalism—the question of how much power the federal government should hold relative to the states.

Poison ivy can cause rashes year-round since all parts of the plant contain urushiol, the oil that triggers our allergic response.

Existentialist writer Jean-Paul Sartre coined the famous phrase 'Hell is—other people' in his play 'No Exit'

Fireworks-related ER visits are on the rise—in 2024, they increased by 52% as compared to the prior year.

Coral reefs get their colors from zooxanthellae—microorganisms that line corals' digestive tracts and provide them with sugars in exchange for a home within this protective tissue.

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

Play the role of a student in a game where you try to navigate college and remain debt-free, selecting different income levels, high school experience, race, ethnicity, and more.

The word 'jazz' evolved from 'jasm,' 19th-century American slang for 'energy'

Astronauts have repaired genetic damage in space using CRISPR—a molecular tool that can make precise changes to DNA and is used in single-celled organisms to attack invasive viruses.

Clever Hans was a 1900s horse that was believed to be able to solve math equations, tell time, and read and comprehend German, until a psychology student discovered how he got his answers.

An initial public offering or 'IPO' is the process of a private company becoming public by putting shares of the company on the stock market for purchase.

Three Ebola species are responsible for most large outbreaks of the disease, yet the only approved Ebola vaccine is known to work against just one of them.