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Is Watching Scary Movies Good for You?

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You Asked: Is Watching Scary Movies Good for You?

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Watching scary movies and horror flicks can come with some surprising health benefits, like burning calories and improving mood

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On many winter days in New Delhi, if you look at the weather app on your phone, it will sum up the forecast in one word: smoke.

Step outside, and it becomes clear why. As the temperature drops and wind speeds fall, allowing pollutants from the city's swarm of cars--more than 9 million and growing--and fumes from nearby factories to linger in the air, the Indian capital is enveloped by a thick smog. Depending on how bad the pollution is, the haze fluctuates from a sickly yellow to a dark, cough-inducing gray. The effect is deadly, with one 2015 study blaming the city's deteriorating air quality for as many 30,000 early deaths a year.

Those who can afford them have been buying antipollution masks and air purifiers for their homes. But many of Delhi's 25 million inhabitants, like 45-year-old Vikas Jadav, have no choice but to spend hours outdoors, breathing the toxic haze on a daily basis. Jadav drives one of the city's distinctive black-and-yellow three-wheeled taxis. The vehicle has no windows. From two sides, it is open to the elements. All around Jadav, cars and trucks belch out toxic petrol and diesel fumes. "I came here 10 years ago," he says. "Every year, I find I cough more." But there is nothing he can do about it. The only solution for him, he says, is to not think about it. "This is my work," he says.

Delhi ranks high on a World Health Organization (WHO) list of cities with unhealthy levels of air pollution, but it is far from alone. WHO research found that 90% of the world's population lives in areas with unsafe air-pollution levels. And it's not just cities in the developing world, like Beijing, that face dirty air--Western metropolises like New York City and London are on the list as well. At the beginning of December, Paris was hit by some of the worst air pollution in a decade, leaving the Eiffel Tower cloaked in smog. For all the deserved focus on climate change as the planet's major environmental threat, a much older one--bad air--is still a persistent danger.

Economic growth in places like Delhi and Beijing has led to the rapid construction of coal-fired power plants, quick factory construction and traffic-choked streets. Regulations--to the extent that they exist in these places--receive little attention from the officials charged with enforcing them.

Most European cities enjoy strong environmental protections, but they've still been hit by a wave of smog in recent years. Here the problem centers on the switch to diesel vehicles. Those cars--which drive along increasingly crowded streets--are actually better for the climate than gasoline-powered cars, but they emit more of the pollutants that directly harm human health. "In London, you can actually smell the pollution," says Simon Birkett, the founder of the NGO Clean Air in London. "Go down Oxford Street, you can literally smell it."

A slew of previous research has shown that poor air quality hurts the cardiovascular and respiratory systems, contributing to ailments like lung and heart disease. But scientists are gaining a better understanding of the damage that even low levels of pollution can do to the body. When fine particulates--tiny particles of air pollution that cause haze--enter the body, they can harm the brain and damage developing fetuses, among other effects.

Today some 7 million people around the world die prematurely thanks to air pollution, and the scale and seriousness of the problem has finally caught the attention of politicians. European cities like Paris and Berlin have implemented restrictions on vehicles to limit smog. London Mayor Sadiq Khan--who made the British capital's worsening air pollution a key issue in his campaign--just committed to spending more than $1 billion on initiatives aimed at addressing the issue, primarily by overhauling the city's thousands of buses. Diesel-vehicle drivers will soon need to pay $15 just to enter the city center.

Developing countries like India are still doubling down on polluting coal, arguing they need cheap energy to keep their economies growing. But public-health experts argue that air pollution exacts its own toll on the economy--the World Bank pegs the cost of bad-air-related deaths at about $225 billion a year. "You have to make the case that pollution is a big problem," says Dr. Phil Landrigan, a pediatrician and environmental-health expert at New York City's Mount Sinai Medical School. "You make the case on public-health grounds, you make a moral case, you make a business case."

Air pollution, more than any other environmental threat, truly affects everyone. The rich and the poor still breathe the same air--which means we should all have an interest in cleaning up the skies.

--With reporting by NIKHIL KUMAR/NEW DELHI

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On many winter days in New Delhi, if you look at the weather app on your phone, it will sum up the forecast in one word: smoke. Step outside, and it becomes clear why.

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If you feel your smartphone is hurting your health or relationships, the answer may be yes.

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You Asked: How Can I Avoid Getting Sick on Vacation?

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Skip the supplements and adjust your behavior.

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You Asked: Is It Bad to Exercise on an Empty Stomach?

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You Asked: Is It Bad to Exercise on an Empty Stomach?

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Skipping food before working out won't hurt. But eating before a sweat session is a better choice for most people.

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A new kind of light therapy may soon help you bounce back from the jet lag that stems from changing time zones

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You Asked: Can Indoor Plants Really Purify the Air?

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Indoor plants are famous for being nature's air purifiers. But do indoor air purifying plants live up to their reputation?

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Here's Why Eating More Slowly May Help You Lose Weight

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Eating slowly, cutting out after-dinner snacks avoiding eating within two hours of going to bed was linked to lower obesity.

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Why Pig Organs Could Be the Future of Transplants

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Animal-to-human exchanges of tissues like ones used by CRISPR, could solve serious medical conditions, but they're controversial.

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You Asked: Is Intense Exercise Better For Your Health?

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A vigorous, high-intensity workout is great. But easy or moderate exercise, like walking, may offer more bang for your burn.

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You Asked: Should I Take Nutrition Supplements?

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You Asked: Should I Take Nutrition Supplements?

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Some dietary supplements are safe. But experts say you have to treat nutrition supplements and vitamins as if they were prescription drugs

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Whether you're talking, scowling or smiling, a groove forms on your skin the moment you move one of your facial muscles. That groove is perpendicular to the movement of the underlying muscle, explains Dr. Anthony Rossi, a dermatologist at Memorial Sloan Kettering Cancer Center. "For example, forehead grooves are horizontal because our forehead muscle pulls up," Rossi says.

When it comes to your smile, the largest of the lines that form are the "nasolabial folds"-those big parentheses of skin that arc downward from the sides of your nose to the corners of your mouth, explains Dr. Marc Glashofer, a New York-based dermatologist. Those folds appear every time you smile. And as you grow older, those happy-face grooves don't fade away once you stop beaming, Glashofer says.

Happiness Guide

But don't blame your smile. The real culprit is your skin's diminishing elasticity.

Rossi calls the biological changes that hurt your skin's rebound abilities "intrinsic aging." These include breakdowns to the underlying structure of your skin due to factors like fat loss and muscle atrophy. Rossi says your genetic makeup also affects how your hide holds up to years of smiling. "We know different ethnicities age differently," he says, adding that your skin's natural melanin concentrations and oil production also play a role in how quickly your smile groves will start to leave their mark. Unfortunately, many of those variables are out of your hands.

You Asked: Your Top 10 Health Questions Answered

Illustration by Peter Oumanski for TIME

But here's one factor you can control: ultraviolet radiation exposure from sunlight. "This is actually the number-one cause of wrinkles," Glashofer says. The more sun your skin soaks up, the more its connective tissue breaks down, leaving it less firm and less elastic.

For that reason, Glashofer and Rossi recommend the daily use of a sunscreen that guards against both UVA and UVB rays. Both dermatologists also advise keeping your skin well hydrated, which starts with drinking plenty of water. Rossi says H2O is a major component of your dermis-the layer of skin that houses many of the structural proteins that keep you looking youthful. He also suggests using a skin moisturizer, which helps your skin lock in water.

Retinol-based creams are also aces at fending off age lines, Rossi says. "They not only promote the formation of new skin cells, but they also increase collagen production, which improves the appearance of wrinkles and slows their formation," he explains.

Of course, you could also try to limit your smiles. But you'd be forgoing the immune system-boosting, stress-lowering benefits of a good laugh. "I would never tell anyone to avoid smiling," Glashofer says. "You are truly blessed to have an abundance of smiles in your life."
Read next: You Asked: Does Laughing Have Real Health Benefits?

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You Asked: Can Smiling A Lot Really Cause Wrinkles?

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Whether you're talking, scowling or smiling, a groove forms on your skin the moment you move one of your facial muscles. That groove is perpendicular to the movement of the underlying muscle, explains Dr. Anthony Rossi, a dermatologist at Memorial Sloan Kettering Cancer Center.

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You Asked: Why Do Certain Songs Get Stuck in Your Head?

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Songs that get stuck in your head-or earworm songs-can be annoying. Here's what to do when you can't turn off the music inside your head.

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You Asked: Should I Shower In the Morning Or At Night?

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should i shower in the morning or at night

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is it better to shower at night or morning

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You Asked: Should I Shower in the Morning Or at Night?

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Whether you're a night or morning showerer, both have pros and cons-and some of them are unexpected.