Avalon Nuovo

If the darkening evenings and turning leaves induce a mild sense of dread in you every year, you’re not alone.

With the arrival of winter, many of us experience Seasonal Affective Disorder — which bears the appropriate acronym of SAD — and can bring on a depressed mood, loss of interest in things that you normally enjoy, and changes in sleep and appetite. While there aren’t conclusive figures, it is thought to affect between one and nine percent of the population, depending on where you live.

Although we may think of it as being a distinct affliction of its own, SAD is actually classified as either bipolar or major depressive disorder, but with a seasonal pattern. This means that people who experience it feel much worse in the fall and winter and relatively balanced or potentially even manic in the summer months, explains Kathryn Roecklein PhD, an associate professor of psychology at the University of Pittsburgh who studies the condition.

“Depression itself is pretty episodic,” says Roecklein. “You have a period of it, and then it goes away. The distinction [with SAD] is the seasonal recurrence.” It also appears that SAD is two to four times more common amongst women.

Even though we are making greater efforts as a society to recognize the importance of our mental health, it can be tempting to dismiss SAD as a touch of the “winter blues” and to try to get on with life as usual. But the best approach, Roecklein says, is to accept and recognize that it’s something that we may genuinely suffer from — and need treatment for. Just as we would for heart disease or diabetes.

Why does winter make us SAD?

The story of SAD starts with our circadian rhythm — our internal body clock that tells us when to eat, go to sleep and wake up.

For the most part, we tend not to think too much about this system unless we have an unexpectedly late night or take a long-haul flight. But chronobiologist Emily Manoogian PhD says it plays a much more significant role.

“The circadian system is directly tied to how our brain functions, and this affects our cognitive ability, our behavior, our mood and our ability to remember things,” says Manoogian, who researches circadian rhythms at the Salk Institute for Biological Studies in California. “The circadian system is important for making sure that throughout your body and brain, regions are talking to each other the way that they should be and everything is balanced. We know that circadian disruption is heavily associated with every form of affective disorder — such as major depressive disorder, bipolar disorder, etc.”

Increased darkness in the fall and winter months is something that humans on much of the planet have experienced for thousands of years, but our technological advancement — in particular, artificial light — is interfering with this natural occurrence. Light is one of the most powerful stimuli for our circadian systems, and since the advent of electricity we’ve been sending our bodies a lot of mixed messages.

“This environment that we’ve created is inherently disruptive — it’s not lights on and off at a constant time to allow for a proper rest for our body; it’s lights on when we need to be up for work on some days, and then off later on other days,” explains Manoogian. “That creates this kind of social jetlag. That’s also going to make it a lot harder to sleep, and it can compromise health over time.”

Manoogian is also not a fan of daylight savings time. She says, “It shifts our exposure to sunlight later in the day and thus shifts our biological clocks. In the summer, we are getting sunlight later than we should, and when days are shorter, we are waking up in darkness. But the problem is that we still have to start work or school at the same times. This means that our schedules and our body are on different times, and this disrupts the circadian system.”

Although there is no evidence connecting it directly to SAD, daylight savings time is known to be widely disruptive to society and potentially even associated with cardiac health risks. There’s a growing movement to do away with the twice-annual time switch in several Canadian provinces, where Saskatchewan and (as of 2020) the Yukon Territory stick to the same time year-round, and similar proposals are being considered in other jurisdictions around the world.

What can you do?

As with any disorder, your treatment depends in part on severity. If SAD is significantly disrupting your life or making you feel as though life is not worth living anymore, it’s deeply important for you to reach out immediately to a mental health professional who can support you. Roecklein says that effective treatment options include taking medication, receiving cognitive behavioral therapy tailored to treating SAD, or using a SAD lamp (which delivers a higher dose of light than regular indoor lighting), but they should be explored under professional guidance.

If you’re wondering what to do because you’ve already bought a SAD lamp to use on your own, Roecklein says that there could be side effects. The most likely one, which is mild, is that you will feel it isn’t effective. This doesn’t mean that it can’t be the right therapy for you in conjunction with professional guidance — for instance, you could be using it at the wrong times or for the wrong duration. At the other end of the scale, mania is a very rare but significant side effect of improper use.

However, there are some relatively easy things you can do to support your circadian rhythms in everyday life. And while these aren’t guaranteed treatments for SAD, they can help give your body a stabilizing sense of routine.

Keep a consistent schedule, especially if you work from home

This doesn’t need to be a rigid, planned-down-to-10-minute increments affair; it’s more about keeping the stimuli that speak to your circadian system arriving roughly when it expects them, says Manoogian. Social interactions and food are two important circadian cues, so having regular mealtimes and breaks where you make a phone call, go for a walk or talk with other members of your household can really help.

Exercise is another important cue

It’s hard to get — and stay — motivated during a winter of pandemic-related restrictions, so any exercise is better than no exercise at all, emphasizes Manoogian. However, if you do choose to exercise outside, she says that the morning is a good time for your body to get some much needed natural light.

The only time for you to avoid exercising, if possible, is right before bed. When you do, it sends a confusing message to your body that night is a time to be active rather than to prepare for sleep.

Maximizing your light exposure is key

How much light we experience at different times of the day is important. Increasing the amount of light you get in the morning is helpful, whereas increasing your light exposure in the evening can be counterproductive.

So if your morning commute has changed from an hour in the car or on transit to a quick switch from your bed to your desk, you’re losing out on a lot of daylight that you are used to receiving just when you need it most. Taking a morning walk before you start your day, or even sitting near a bright window for the first half of your day can really help.

At night, reducing your light exposure and making your sleeping environment as dark as possible is also of huge benefit, explains Roecklein. “Most circadian biologists and sleep researchers I know have blackout shades and no night lights in their rooms — we don’t even have clocks with illuminated screens.”

No, it’s not just you — 2020 may be making your SAD worse

It’s difficult to separate the impacts of factors like the COVID-19 pandemic, the associated economic downturn and the psychological toll of the current political climate. But Roecklein has noted, at least anecdotally among the people in her SAD study, that there seems to be a higher instance of what psychologists refer to as “negative anticipatory cognitions” — where people consistently expect things to be worse in 2020 than in other years.

Roecklein also notes that experiencing negative life events — such as a bereavement, job loss or some other major change that requires large adjustment — as well as reduced opportunities for social and physical activity are additional risk factors for SAD. These areas of our lives have all been significantly impacted by COVID-19, so she and her colleagues anticipate a higher risk of people experiencing SAD this year.

However, there may be one small silver lining to the current situation, says Manoogian. While routine is very important for our bodies, a regular 9-5 work day can be very unnatural for those of us who aren’t morning people.

“The typical workday schedule is an artificial time that not everyone is able to stick to,” she explains. “If you work from home and you have a little bit of freedom about when you work, this could provide a very interesting opportunity for you to actually coordinate your schedule more with your internal clock.”

Sometimes it’s OK to doomscroll

Lastly, Roecklein wants to stress that although a routine is important, we are living through monumental events that are unfolding right before our eyes. And if we occasionally want to stay up a few hours later to feel better informed or more connected to other people experiencing the same thing… that’s actually fine.

“We take a moment to care for ourselves by thinking about the pros and cons. So there may be some nights where staying up late and doomscrolling is a choice one might make for good reasons,” says Roecklein. “But then on other nights, when we think about what we want most for ourselves — like better energy in the morning, a more positive mood, better alertness for the endless Zoom meetings — we might be more motivated to turn off devices, turn off the TV, dim the lights, and do all of those things that can help you wind down. Give yourself the chance to make that decision, and make the decision that’s right for you.”

Watch Emily Manoogian’s TEDxSanDiegoSalon Talk on your circadian clock here: 

ABOUT THE AUTHOR

Mary Halton is Assistant Ideas Editor at TED, and a science journalist based in the Pacific Northwest.

This post was originally published on TED Ideas. It’s part of the “How to Be a Better Human” series, each of which contains a piece of helpful advice from someone in the TED community; browse through all the posts here.

This field went from dirt to dense forest in just two years. Courtesy of Afforestt

When you look at a row of empty parking spots, what do you see?

Many of us would see it for what it is — a place that could be filled with cars and trucks.

But to eco-engineer Shubhendu Sharma, it’s a space to be planted with trees and turned into a compact yet mighty forest.

What’s more, he believes these tiny forests can thrive anywhere, including our most crowded and polluted cities where they can help maintain clean air and water and provide habitat for animals and insects. “A forest is not an isolated piece of land where animals live together,” says Sharma, a TED Fellow. “A forest can be an integral part of our urban existence.”

Most of us know just how essential trees are to our health and to the planet’s. Yet millions of hectares of forest are cleared every year due to farming, ranching, logging and construction, making deforestation one of the biggest contributors to greenhouse gas emissions. The World Wildlife Foundation estimates that 20 percent of the Amazon rainforest and surrounding ecosystems have already been lost, threatening a vital carbon sink, and Brazilian president Jair Bolsinaro is opening up previously protected parts to commercial development.

A before-and-after from Afforestt.

After two years, they achieved this inviting patch of greenery.

Inspired by the work of Japanese scientist Akira Miyawaki, Sharma built a forest in the backyard of his family’s home in northern India in 2010. An industrial engineer at the time, he planted 224 spindly young trees and shrubs In the 75-square-meter (or 807-square-foot) plot. They grew and flourished, and a dozen species of birds came to check them out. The plantings created welcome shade, and their roots were able to absorb even the abundant monsoon rains. After a year, he had his own forest.

Since then, Sharma has founded a company called Afforestt. Its top priority is to bring back natural forests to places where they no longer exist. This means restoring stable ecosystems of plants and animals that used to exist in these spaces. Such systems ordinarily take hundreds of years to evolve, grow and mature together, but Sharma believes it’s possible to do this in as little as 10 years — and he has plenty of examples to prove it. He’s shown you can take a space the size of six or seven parking spots — and create a lush, verdant forest with over 100 trees and shrubs. So far, Afforestt has planted 144 forests in 45 cities around the world.

So, how do you build a complete forest ASAP? By aiming for two things: Density and planting native species.

In terms of achieving density, it’s all about filling a space with trees and shrubs of varying heights. “By making a multi-layered forest, we can fill up an entire vertical space with greenery,” Sharma says. “That way, we can have 30 times more green surface area compared to a lawn or a garden in the same area.” A tiny forest provides a long-term, cost-effective alternative to a traditional lawn. Not only are trees beautiful and great at taking in carbon dioxide, they act as an effective noise buffer and a sponge for air pollution and particulate matter.

Planting trees that are native to your region has specific benefits. Since they’re already adapted to the climate, they require significantly less maintenance than many other non-native species. Native trees also create a welcoming environment for the indigenous wildlife — birds and insects — to thrive. Early studies indicate that these dense forests may actually be able to restore biodiversity at levels comparable to natural forests.

Ready to create your own tiny forest?

Shubhendu Sharma breaks it down into 5 steps:

1. Identify your native species

When beginning a project, Sharma and his team first go to the nearest national park, protected grove, or nature reserve to search for patches of conserved forest. Paying close attention to the number and types of trees in a natural ecosystem will allow you to build your own, he says — for instance, noting the relative proportion of native species will give you an idea of how many to plant. “If you can, collect the seeds, germinate seedlings out of them; that’s the start of the physical work,” he says. (Editor’s note: This is not legal in some places, so please check first.)

If you can’t collect seeds or aren’t legally permitted to do so, you can also ask someone knowledgeable at a local nursery, garden, or agricultural or county extension agent to recommend native species to plant.

This compost tea is for trees to drink, not humans.

2. Nurture the soil

Healthy soil is the basis of a healthy forest. “Find different types of biomass, or organic matter, that can make your soil moist, full of nutrition, and so soft that roots can penetrate into it easily,” Sharma says. His team often uses coco-peat (also known as coco coir; it’s the fibrous husks from the outer layer of a coconut) because it’s highly absorbent and improves water retention in dry soil.

“To loosen up compacted soil, we use pear tree husk or any biomass, which is crunchy in nature,” Sharma elaborates. Peanut shells are OK too. He adds, “It has to have a spring-like property. When you crush it, it should come back to its original shape.” These characteristics are important to help support the roots of your trees.

Instead of adding nutrients or artificial fertilizers, Afforestt adds microorganisms. “We take soil from a natural forest, so we can get the native colonies of microbes and fungi and we multiply their number in what we call compost tea,” Sharma says. Compost tea is a microbe-rich nutrient broth, which is diluted and added to the soil. These fungi and microbes grow and support the root network to allow trees to grow quickly and collectively. While more studies are needed to better understand compost tea, you can add regular compost, which is known to support soil health.

Make sure to fill a space with trees and shrubs of varying heights.

3. Plant your seedlings — but don’t forget the mulch

The key to achieving a dense forest is to arrange the landscape in a beneficial ratio of layers. “We divide our trees into four different layers: a shrub layer, sub-tree layer, a tree layer, and a canopy layer,” Sharma explains. The exact ratio of these layers depends on where you live. For example, a rainforest environment like São Paulo will have a denser canopy layer, while a region with a desert-like climate will have more shrubs. The most successful forests will mimic the composition of the natural environments found in your area.

What really sets the stage for rapid growth is the density of your layers. As trees grow, they communicate through fungal networks that protect against disease and provide nutrients to one another. Mulch plays a vital role in protecting the ecosystem below the soil against harsh environmental conditions — like a breathable, protective blanket over the soil for all seasons. Sharma’s team usually uses straw, but he says the right mulch can be “anything that doesn’t allow water to evaporate back into the atmosphere but is open enough to let the water seep through and reach the soil.” Not only does mulch protect the soil microbiome, it also traps moisture when it’s hot and protects against frost and ice when it’s cold.

4. Tend for a few years

Once your seedlings are planted, you’ll need to perform routine maintenance — watering and weeding — during the first couple of years. But there’s one thing the Afforestt team never does in this time period: They never prune or trim the trees themselves. Since the ultimate goal is to create a lush forest, pruning will counteract that growth process.

Plus, after you reach a certain stage of growth, you’ll be able to stop weeding. “Eventually, the forest becomes so dense that sunlight won’t reach the ground any more. Once sunlight cannot reach the ground anymore, weeds also can’t grow because they need sunlight,” Sharma explains.

5. Let it grow!

Humus is the organic material that naturally occurs in healthy environments. Once it begins to form, then you’ll know it’s time to let your forest be. “Humus is the food for the forest,” Sharma says. “It can only be made on the floor of a natural forest, because it’s a combination of biomass, fungi, dead bodies of insects, microorganisms, earthworms, etc.”

How do you know when humus has formed? “Initially, you will see just leaves on the forest floor, then twigs, and then you’ll see old branches fall, termites coming in to convert that branch into powder. It gets more and more complex and rich,” Sharma explains. “This is the stage when we say, ‘Ok, now no management is the best management.’” Forests can typically be left alone after three years.

If you don’t have the space or time to build your own forest, you can participate in other ways. “What I’d really urge people to do is to go to their local natural forest and learn about their native trees,” says Sharma. Most of us can name multiple dog or cat breeds or the names of numerous fruits and vegetables, so add to your knowledge by learning the names of 25 native tree species. Then look for them in your community.

To expand the Afforestt network, Sharma is partnering with collaborators in other countries and developed a crowdfunding app called Sugi. This allows people to donate and fund forest projects, building a global network around rewilding urban environments. Sharma hopes that by planting seeds of inspiration, the reforestation movement will spread so that more and more land is converted back into forests. While the Afforestt team started in India, it has consulted with groups from many countries, including Cameroon, Australia and Japan. They’ve developed an open-source database with best practices that anyone to use and maintain an up-to-date guide on reforestation.

By planting tiny forests all around the world, Sharma and his team hope to open up people’s eyes to the variety and splendor of native plants. “The biggest challenge is that our perception of beauty has to change,” he says. “There is no one-size-fits-all formula, because Earth is extremely biodiverse. If you go to Dubai and Spain, you see palm trees and if you go to California, you see the same palm trees. That’s a boring world, you know? The beauty of a natural forest is that it’s different everywhere and there is so much to learn. There is so much to enjoy.”

All images: Courtesy of Afforestt. 

Watch his TED Talk now:

ABOUT THE AUTHOR

Kara Newman is a science journalist currently based in New York City.

This piece was adapted for TED-Ed from this Ideas article.

Alamy

From tennis to swimming and soccer, female athletes are at the top of their game right now, but they are still not receiving the support that men do.

Despite accumulating international titles, the US women’s national soccer team are currently having to pursue a gender discrimination lawsuit for equal pay (above, a photo of them from August 2019). In advance of the trial, their governing body, U.S. Soccer, has filed court documents declaring them less skilled than their male counterparts.

But the problem isn’t just that the gender pay gap also exists in sport — even the average woman just wanting to have enough energy to hit the gym regularly is at a disadvantage. The underlying research that makes good nutrition and effective training possible has also all been done on men, says exercise physiologist and nutrition scientist Stacy Sims in her TEDxTauranga Talk. “[During my early research I was told] ‘women are an anomaly, so we don’t necessarily study women in sport nutrition or exercise science’… I looked around and I thought surely with 50 percent or more of the population being female, aren’t the men the anomaly and they don’t know it yet?”

New Zealand-based Sims is on a mission to get the sporting world to recognize that “women aren’t just small men” but have their own set of nutritional and physiological needs.

While everyone’s body is different, there are patterns in physiology that are particular to most women and deeply impact their training. One of these is the menstrual cycle. Sims is frustrated that this isn’t addressed enough in sport and training. “This is one of the reasons girls drop out of sport, because no one talks about it… and wait til you get to perimenopause and menopause; it’s like tumbleweeds.” She has also seen clients in her own practice who have felt it was normal and “easier” for their periods to disappear during intense training.

While some studies have suggested that it can be useful to plan strength training around your menstrual cycle, and that you may even be more at risk of injury in particular stages of your cycle, we are still lacking a large and robust body of research to tailor training and competition around a fundamental aspect of many top athletes’ physiology.

In nutrition, too, Sims says that studies on high intensity interval training, the ketogenic diet and paleo intermittent fasting are all done on (often sedentary) men, then generalized over to the entire fitness population. “If we look at how women have been marginalized [in this process], they’re just assuming that this information is going to work for them as well.”

This mindset is also letting women down when it comes to something as fundamental as equipment, says Lynn Le. She’s the founder of women’s boxing gear and sportswear brand Society Nine (named after the Title IX legislation that made gender discrimination in sport illegal).

A former kickboxing instructor, Le founded the Portland, Oregon company in 2013 after struggling for years with combat sports equipment that hadn’t been designed for women. Clients would show up to her classes wearing children’s boxing gloves, or “some brand’s version of a pink glove, and they almost always didn’t fit the wrist and feel supportive. The material felt super chintzy; it just had no realm of seriousness at all in either fit or quality, and I realised I didn’t really have a place to direct them.”

Le herself had resorted to doubling up on the hand wraps usually used by combat fighters, so she could force her hand into a fist inside men’s gloves that were too big. As women’s hands are narrower than men’s, Le knew that a dedicated design was necessary not just for comfort but for basic safety.

“[In combat sport] your first line of defense is creating that shock absorption through the power of your own body, which is compressing your hand into as close of a perfectly formed fist as you can. If you’re wearing a glove that’s two sizes too big, how on earth can you possibly do that?… You want to enjoy what you’re doing, and to enjoy what you’re doing, you want to wear things that are comfortable, support you and help you prevent injury.”

Le and her development team also came up against the severe lack of research on women’s physiology when they were trying to design shin guards. There were no studies on how to make a suitable fit for women, despite women having a much more variable sizing from the knee down than men do. “We had to go back to high school biology and really try to understand the human body… Women’s bodies are incredible and complicated. They’re way more different in variability than men’s bodies. That’s the number one thing I’ve learned.”

But for Le, founding Society Nine was about more than solving an equipment problem. “The industry wasn’t really interested in representing all self identifying women, from their products to their stories. If they did, they did it in such a way that it tokenized individual women singularly rather than as a collective. So many brands… only talk about being the one, being the champion, being the winner, and that is not a recipe for longevity.”

Her own experience with combat sports changed her life, and created a community for her when she was going through a difficult period. Now she sees an outpouring of the same stories from her customers.

Le’s aim is to make it known that this community exists far beyond what is regularly shown in advertising, and it is welcoming. “Why we train, whether for fitness or competitively, goes so much deeper than glory or attention.” Society Nine works hard to make sure that whenever the company uses the term “women” that it’s defined as “self-identified women”, and it continues to expand its sizing and representation.

The industry is even more alienating for trans women and intersex athletes, who face not only a lack of representation but a serious dearth of research, with debates and disagreements at the highest level about how and whether they can compete.

In terms of what the future looks like, it’s still an uphill battle. Even now, as a professor at the University of Waikato and having held a research position at Stanford, Sims gets asked why it’s important to study women when “we don’t know enough about men.”

She recently published ROAR, a nutrition and fitness guide for women, and she wants to see more women realising the full and unique potential of their bodies. “We can really work with our physiology to improve our health outcomes, to improve our performance. Whether that be walking up the mountain, running a fast 5k, or winning Ironman. Whatever your goal is.”

For Le, the aim is to keep serving her community and to keep having challenging conversations. Though she received a strong welcome when the company started, some of the push back she encountered in the early days still remains. Like sports pro shop retailers telling her that women don’t really come to their store. “Maybe they don’t come into your store because there’s actually no women’s product. There’s no reason for them to enter if they are shown blatantly that they aren’t served or thought about.”

Society Nine also continues to donate equipment to combat sports programs for women and young people across the country. “I want to keep on helping self-identified women and other underrepresented people. I want them to feel seen … What motivates me isn’t just making really beautiful stuff that works. It’s also telling these women’s stories.”

Watch Stacy Sims’s TEDxTauranga Talk now:

ABOUT THE AUTHOR

Mary Halton is Assistant Ideas Editor at TED, and a science journalist based in the Pacific Northwest.

This piece was adapted for TED-Ed from this Ideas article.

iStock

A new technology aspires to harness the powerful human sense of smell to enhance our daily lives.  Someday this approach might even be used to benefit our health. How is this possible? Step one: Just inhale.

We’re living in a playlist world, with many of us curating soundtracks to get us through life’s daily ups and downs, such as a tough commute, sweaty workout, or sleepless night. But what if we could also turn on our own scent playlists — imagine “Peppermint Wake-up”, “Grapefruit Grind”, “Lavender Lullaby” — at those times? You know, like a personal smelltrack? Or smell-list? (Note to the world: Applications for better name now open).

David Edwards, an inventor and professor of bioengineering at Harvard University, is working to turn that dream into a reality. He has created an app, called oNotes— a combo of “olfactory” and “notes”— that is paired with a scent speaker, called Cyrano. Use the app to play the speaker and out wafts a dynamic sequence of scents.

The human nose can distinguish among at least 1 trillion different scents.

While our sense of smell can get overshadowed by the other four senses, there should be no mistake: It is formidable. The fact that humans have a poor sense of smell compared to other mammals was recently refuted as a 19th-century myth. The human nose can distinguish among at least 1 trillion different scents. (A little practice — or even a lot — doesn’t hurt: see the TED-Ed lesson: How to master your sense of smell.) Even though we’re not always aware of our scentscapes and the impact they’re having, a chance whiff has the power to stop us in our tracks, stir up emotions and memories, and attract us to (or repel us from) its source.

For humans, scent and survival are inextricably linked. Unpleasant odors elicit immediate involuntary responses. Our heart rate ratchets up when we smell a raging fire, and our disgust is evoked by the pungent aroma of spoiled food. As in much of the animal kingdom, we humans transmit signals to each other through scent, whether it’s via pheromones, selective (and unconscious) hand-sniffing after we shake hands with others, raised hormone levels, or our ability to differentiate between the odors of “self” and “non-self”.

Scientists are only now delving into how particular scent molecules affect our brains. What they do know is that once a scent binds to the olfactory receptors in our nasal epithelium, “there’s an electrical signal that’s delivered directly to the brain’s limbic system, an area associated with emotion and memory, [which sets] off a cascade of neurologic and biochemical consequences,” says Edwards. By contrast, other sensory inputs — tastes, touches, sights and sounds — are routed through different parts of the brain first, which moderates their effects.

In a human sperm cell, olfactory receptors register chemicals and determine the way the cell moves.

Humans contain a huge array of olfactory receptors located outside of our noses. They’re found throughout the body in places such as the brain, lungs, gut, kidneys, and even sperm cells. These receptors act as docking and signaling systems, playing a crucial role in the conversations constantly taking place inside us. In a sperm cell, for instance, olfactory receptors register chemicals and determine the way the cell moves — and whether it reaches a certain egg of interest.

Today, we find ourselves immersed in a dramatically altered, controlled and artificial scentscape. There are “all of these sensory signals that we’re not used to,” says Edwards, and “our bodies don’t quite know what to do with those signals.” Just think of the overload that we experience during a single visit to a shopping mall, where perfumes, warm pretzels, new sneakers and more compete for our noses. Amid the onslaught, the scents of the natural world that humans evolved with over millions of years are diminishing or disappearing from our lives.

This shift in our olfactory environment could be having negative effects on our health, contends Edwards. In recent decades, epidemiologists have observed a huge global increase in the number of people diagnosed with diabetes: from 108 million in 1980 to 422 million in 2014, according to the World Health Organization. Indeed, some research in laboratory animals has indicated that smell can impact metabolic health and diet-induced obesity. “You can think of the olfactory bulb as a kind of fuel gauge. Upon sensing aromas, particularly food aromas, it will rev up metabolism,” Edwards explains. This process may then trigger cravings, which have historically helped our species survive, but now sometimes cause us to overeat or eat unrewarding foods.

One experiment has shown that when fasting women inhaled the scent of chocolate, they could go longer without eating.

Scent playlists might be used to “bring back to the body sensory signals that it knows how to understand,” according to Edwards. One study found that when people were exposed to a sweet or savory smell, they developed a greater appetite for the food that matched the smell. And, “if you expose humans to a sweet aroma before a savory meal, they’ve been shown to consume fewer calories, and vice versa,” Edwards says. Another experiment has shown that when fasting women inhaled the scent of chocolate, they could go longer without eating. It appears as if the smell of chocolate alone “affects their system as if they’ve actually started eating it,” says Edwards, which triggers the hormonal responses associated with satiation and appetite suppression. Yet another study found that when people’s taste experience was augmented with aroma, they tended to feel more satiated. These and other experiments point to the potential for scent-based therapies and technologies to subtly mediate how much people eat and diminish unwanted cravings.

Scent playlists might also be used to shift our emotional states. Certain scents have the power to evoke vivid autobiographical memories, be they of the Proust-and-madeleine kind or the sterile-hospital-childhood-injury variety. The more profound the experience associated with the aroma, the greater the emotional responses in the brain. What’s more, being exposed to odors with uplifting personal associations has been shown to disrupt cravings, decrease inflammation, and increase positive emotions. In studies, certain naturally occurring scents have been found to have stimulating (peppermint, coffee), calming (lavender, magnolia), or joy-inducing (freshly cut grass) effects on human subjects.

Could scents be used in conjunction with psychotherapy to treat people with addiction?

Cyrano, Edwards’s scent speaker, is all about aromas of the uplifting kind.It currently works with three evocatively-titled cartridges: Surfside (guava, suntan lotion, lime and sea breeze), Einstein (rosemary, lemon and peppermint) and Central Park (rain, waffle cone, jasmine and cut grass). Each is meant to elicit a specific physiological response in users (relaxation, focus, and energy, respectively). The individual aromas are made from essential oils or synthetic molecules. Like a musical playlist, the scent compositions change over time, switching every 8 to 10 minutes. This variation prevents olfactory fatigue, which occurs when our olfactory receptors saturate and we become inured to a scent after a while (think of how intensely a cafe smells when you first enter it, but how little you notice the ambient coffee aroma after you’ve used the WiFi for an hour).

So, how is the scent speaker working for its users? While an experiment hasn’t yet been done in the lab, Edwards has conducted one small pilot study on the effects of the device in the workplace. In it, 77 employees at Siemens Corporation were given two scent cartridges (Surfside and Einstein) to use at their discretion over a six-week period. The results: 80 percent continued to use the device after the first week, 50 percent reported feeling positive effects, and those who used it more frequently saw a greater improvement in their scores on an emotional intelligence test. Interestingly — and understandably — 3 PM was a popular time for people to play their scent speakers.

The office isn’t the only place Edwards can see the device being beneficial, though. This summer, Cyrano will be installed in cars from a high-end European automaker. Edwards is also set to launch a product that is designed to enhance users’ culinary experiences by emitting “flavor clouds” like ginger, chocolate and raspberry. Another research question at the front of his mind is: Could scents be used in conjunction with psychotherapy to treat people with addiction?

Someday, Edwards hopes that people can use technology to tap into scent for a quick pick-me-up, dose of calm, or way to find more enjoyment from the food they eat. In many ways, we humans have reached a day of reckoning when it comes to realizing just how much we’ve altered our environment. But instead of bemoaning the state we’re in, Edwards is encouraged by the work being done in this area. “We’ve been playing around with sensory signals, not recognizing how big a deal they are. Now that we’re understanding the consequences, there’s an effort to correct them,” he says. “It’s ultimately good news.”

Watch this TED-Ed video to learn how to master your sense of smell:

Watch David Edwards’s TEDxHarvardCollege talk: