Up to 400 milligrams of caffeine a day is considered safe

Coffee is, generally, good for your health

While overconsumption certainly has its drawbacks—hello, not sleeping until the sun rises—on the whole, coffee is fine, even beneficial, for your health. It can even help prevent serious health conditions, like heart attacks and liver cancer.

Coffee is, indeed, addictive

Caffeine enters the brain through the bloodstream, where it blocks receptors that cause us to feel tired and enables stimulants like dopamine to increase alertness and focus. Over time, the brain begins to expect this level of stimulation, and caffeine addiction can develop. Caffeine withdrawal causes headaches, irritability, and fatigue.

Coffee contains an average of 15mg of caffeine per fluid ounce

Coffee has three times the amount of caffeine contained in most caffeinated sodas, but significantly less than espresso and cocoa powder.

A caffeine calculator

This simple calculator takes your preferred caffeinated drink and your body weight to determine how much is the right amount, and how much might kill you. In case you've ever had the morbid curiosity about just how much of that tea you'd have to drink to doze off forever. Find out your moderate and lethal doses here, as well as some extra info on caffeine consumption.

Even brief physical activity can trigger the release of neurotransmitters that provide mental health boosts

A couple of minutes of light walking or stretching can increase feelings of energy and reduce fatigue, not just through the release of endorphins. Exercise can also provide self-regulation and improve task engagement and focus in those with certain mental health disorders, like ADHD.

See how much daily sugar substitute intake the FDA considers to be safe

The agency states in this PDF graphic that a person weighing about 132 pounds would have to consume roughly a couple dozen sweetener packets daily—or more—to reach unsafe levels of consumption. The accumulated consumption would be across all sources, including diet beverages, sugar-free candies, and actual packets added to coffee.

Some data shows cold showers can help with depression

An icy water exposure can lead to the release of norepinephrine, cortisol, dopamine, and other stress hormones that are beneficial, among other potential effects. Some data shows that this type of exposure can help combat depression symptoms among some patients, but more research is still needed. (Some users may encounter a paywall.)

Certain medications that affect blood flow or mood boost the risk of heatstroke

Drugs that narrow blood vessels, beta blockers that regulate blood pressure, diuretics, antidepressants, and antipsychotics can all affect the body's ability to regulate its internal body temperature, and so individuals taking these medications need to take special care in extreme heat and when exercising in hot conditions.

Kava, kratom, St. John's Wort, and green tea extract present health concerns

Consumer Reports, which tests supplements for safety, urges consumers to avoid these four supplements due to safety warnings from researchers and public health authorities.

Can microdosing improve mental health?

Animal studies involving microdoses of psilocybin, the psychoactive component in magic mushrooms and ketamine, found it helped to alleviate anxiety and inflammation, an immune response that can cause damage when chronically active. Human studies are ongoing. In at least one double-blind study, where researchers and patients don't know who got a placebo versus the real thing, about half of the participants incorrectly guessed they had been given placebos.

The depression paradox refers to a lack of energy to take action to help alleviate it

Activities like exercise, even at low levels, have been shown to alleviate some of depression's symptoms for some people. However, depression saps energy levels, making it particularly difficult to motivate oneself to take helpful action.

The side effects of falling back and springing forward

Daylight saving time can interfere with a person’s sleep schedule, but it also has been linked to increased rates of depression, heart attack, stroke, cancer, and car accidents. UT Southwestern’s Dr. Joseph Takahashi explains why the time change is bad for your brain and health.

Eating too much salt can worsen vertigo

High salt intake can cause fluid retention in the inner ear, worsening vertigo. Slashing sodium amounts (and caffeine and alcohol consumption) are particularly recommended for those suffering from Ménière's disease to help stabilize inner ear fluid levels.

The myth of sugar rushes vs. the reality of sugar crashes

It's generally accepted that sugar rushes are a myth, and that hyperactivity is a more psychological experience. However, there is real science behind the rare sugar crash that primarily impacts those with diabetes. Read this article to understand how historical and cultural factors have shaped sugar perceptions, and how low blood sugar can trigger shakiness, fatigue, weakness, and more in diabetes patients.

Fantasy sports can have adverse health effects

Experts warn that fantasy sports, including fantasy football, can encourage obsessive use because they offer hits of dopamine. Daily fantasy games, which function more like gambling, are especially problematic.

US depression rates at historic high among adults

More than 18% of US adults reported that they currently have or are being treated for depression in both 2024 and 2025. In the 2025 survey, more than 11,000 adults were surveyed. The numbers have ticked upward since 2015—by about 8 percentage points—with most of the increase occurring from the 2020 pandemic onward.

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.

Bupropion is the only antidepressant approved for the preventive treatment of SAD

Clinical trials showed a 44% reduction in risk for recurrence of SAD for those who took the drug compared to a placebo group. Bupropion is a norepinephrine–dopamine reuptake inhibitor, which increases dopamine (other common antidepressants, known as selective serotonin reuptake inhibitors, sometimes can suppress dopamine, but not always).

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.

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

Unlike milder fears, phobias may get in the way of proceeding with your life

Clinicians may recommend exposure therapy—exposing oneself to the thing triggering fears in some doses—as one way to help overcome a fear.

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

Learn the differences between mild cognitive impairment and age-associated memory loss

Mild cognitive impairment is a condition in which people experience more thinking and memory problems than expected for their age. It's often associated with depression and anxiety. Daily routines, writing things down, and healthy lifestyle choices can help cope with the condition, but there's no cure. The condition elevates the risk of developing dementia and Alzheimer's.

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.

Blood pressure readings correspond to the peaks and valleys of heart beats

Pushing 2,000 gallons of blood through the body every day exerts a force known as blood pressure. Blood pressure is highest during the heart's contractile phase, known as systole, which forces blood through the circulatory system, and lowest during the heart's resting phase between beats, known as diastole.

Low cell division rates in heart cells make heart cancer particularly rare

The heart's location in the chest also offers protection from external cancer-causing factors. The disease affects about 3 in every 10,000 people, though most cases arise from metastasis from other body parts.

What causes high cholesterol?

Cholesterol is a complex health issue, and for a long time, the American Health Association recommended Americans not eat more than three eggs a week to avoid it. But scientific advancements on the impact of different types of cholesterol revealed eggs aren't so bad. So what is it, and how does it effect us? Dive into the digestive tract here.

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

After the Boston Tea Party, colonists switched to coffee, which became the main morning drink for revolutionaries.

Bone marrow (soft tissue found inside certain bones) generates roughly 500 billion new blood cells each day

Larger animals like giraffes, elephants, and blue whales have developed a unique defense against cancer, a phenomenon known as Peto's Paradox

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

The first steps to rebuilding your credit score include getting to know exactly what's on your credit report and figuring out how far you are from the '700 club,' or 'good score' range.

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.

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

Crows are believed to have intelligence on par with a seven-year-old child and demonstrate complex behaviors, from problem-solving with tools to recognizing human faces.

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.

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

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

As of 2025, the most cited papers in science include a review of graphene, methods to improve image recognition, streamlining electron density calculations, and optimizing protein studies.

For centuries, Niagara Falls has been a magnet for daredevils seeking to conquer one of nature's most powerful wonders, with its 200-foot drop and water rushing at 32 feet per second with 280 tons of force.

This site reaches millions of visitors who are tired of AI chatbots and seeking human connection. Pretend to be an AI chatbot and ask questions, provide answers, and draw for people in real time.

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.

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.

Memecoins are a type of cryptocurrency—a form of digital currency with a wide variety of uses—created around popular 'memes,' or viral internet jokes.

44% of Americans say they pray at least once a day—discover how your state's religiosity stacks up against the rest of the country.

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.

US intelligence allegedly pursued more than 600 schemes to assassinate Cuban revolutionary Fidel Castro.

The boiling temperature of water decreases with increasing elevation because the molecules need less energy to overcome the lower atmospheric pressure associated with thinner air.

See how Budweiser's famous Clydesdales spend their days at Warm Springs Ranch, where roughly 70 to 80 of the beer brand's giant horses can be found at any given time.