The annual pattern of winter depression and melancholy – better known as seasonal affective disorder, or SAD – suggests a strong link between your mood and the amount of light you get during the day.

To put it simply: The less light exposure one has, the more one’s mood may decline.

Wintertime blues are common, but about 10 million Americans are affected every year by a longer lasting depression called seasonal affective disorder. Along with low mood, symptoms include anxious feelings, low self-esteem, longer sleep duration, constant craving for carbohydrates and low physical activity levels.

I am a nutritional neuroscientist, and my research focuses on the effects of diet and lifestyle factors on mood and brain functions such as mental distress, resilience and motivation.

Through my research, I have learned that seasonal affective disorder can strike anyone. However, people with a history of mood disorders are at a higher risk. In particular, young adults and women of all ages have an increased susceptibility.

Why seasonal depression happens

When daylight saving time ends each fall, the one-hour shift backward reduces the amount of light exposure most people receive in a 24-hour cycle. As the days get shorter, people can experience general moodiness or a longer-term depression that is tied to a shorter exposure to daylight.

This happens due to a misalignment between the sleep-wake cycle, eating schedules and other daily tasks. Research shows that this mismatch may be associated with poor mental health outcomes, such as anxiety and depression.

Our sleep-wake cycle is controlled by the circadian rhythm, an internal clock regulated by light and darkness. Like a regular clock, it resets nearly every 24 hours and controls metabolism, growth and hormone release.

When our brain receives signals of limited daylight, it releases the hormone melatonin to support sleep – even though we still have hours left before the typical bedtime. This can then affect how much energy we have, and when and how much we eat. It can also alter the brain’s ability to adapt to changes in environment. This process, called neuronal plasticity, involves the growth and organization of neural networks. This is crucial for brain repair, maintenance and overall function.

It is possible to readjust the circadian rhythm to better align with the new light and dark schedule. This means getting daylight exposure as soon as possible upon waking up, as well as maintaining sleep, exercise and eating routines that are more in sync with your routine prior to the time change. Eventually, people can gradually transition into the new schedule.

The intimate connection between serotonin and melatonin

Serotonin is a chemical messenger in the brain that is a key player in regulating several functions such as mood, appetite and the circadian rhythm. Serotonin also converts to melatonin with lower light intensity. As mentioned above, melatonin is a hormone that regulates the sleep-wake cycle and signals the brain that it’s time to sleep.

Less daylight exposure during winter months leads to the conversion of serotonin into melatonin earlier in the evening, since it gets dark earlier. As a result, this untimely melatonin release causes a disruption in the sleep-wake cycle. For some people this can cause moodiness, daytime sleepiness and loss of appetite regulation, typically leading to unhealthy snacking. People with seasonal affective disorder often crave foods rich in simple sugars, such as sweets, because there is an intimate connection between carbohydrate consumption, appetite regulation and sleep.

Strategies to combat the winter blues

In winter, most people leave work when it’s turning dark. For this reason, light therapy is typically recommended for those who experience seasonal affective disorder, or even shorter periods of seasonal funk.

This can be as simple as getting some light shortly after awakening. Try to get at least one hour of natural light during the early morning hours, preferably about one hour after your usual morning wake-up time when the circadian clock is most sensitive to light. This is true no matter what your wake-up time is, as long as it’s morning. For people living at northern latitudes where there’s very little sun in winter, light therapy boxes – which replicate outdoor light – can be effective.

You can also improve your sleep quality by avoiding stimulants like coffee, tea or heavy meals close to bedtime. Exercising during the day is also good – it increases serotonin production and supports circadian regulation. A balanced diet of complex carbs and healthy proteins supports steady serotonin and melatonin production, and practicing downtime before bed can reduce stress.

Taking these small steps may help the circadian rhythm adjust faster. For the millions with mood disorders, that could mean happier times during what are literally the darkest days.

Lina Begdache, Associate Professor of Health and Wellness Studies, Binghamton University, State University of New York

This article is republished from The Conversation under a Creative Commons license. Read the original article.

You saw it at Thanksgiving, and you’ll likely see it at your next holiday feast: piles of unwanted food – unfinished second helpings, underwhelming kitchen experiments and the like – all dressed up with no place to go, except the back of the refrigerator. With luck, hungry relatives will discover some of it before the inevitable green mold renders it inedible.

U.S. consumers waste a lot of food year-round – about one-third of all purchased food. That’s equivalent to 1,250 calories per person per day, or US$1,500 worth of groceries for a four-person household each year, an estimate that doesn’t include recent food price inflation. And when food goes bad, the land, labor, water, chemicals and energy that went into producing, processing, transporting, storing and preparing it are wasted too.

Where does all that unwanted food go? Mainly underground. Food waste occupies almost 25% of landfill space nationwide. Once buried, it breaks down, generating methane, a potent greenhouse gas that contributes to climate change. Recognizing those impacts, the U.S. government has set a goal of cutting food waste in half by 2030.

Reducing wasted food could protect natural resources, save consumers money, reduce hunger and slow climate change. But as an agricultural economist and director of the Ohio State Food Waste Collaborative, I know all too well that there’s no ready elegant solution. Developing meaningful interventions requires burrowing into the systems that make reducing food waste such a challenge for consumers, and understanding how both physical and human factors drive this problem.

Consumers and the squander sequence

To avoid being wasted, food must avert a gauntlet of possible missteps as it moves from soil to stomach. Baruch College marketing expert Lauren Block and her colleagues call this pathway the squander sequence.

It’s an example of what economists call an O-ring technology, harking back to the rubber seals whose catastrophic failure caused the Space Shuttle Challenger disaster in 1986. As in that event, failure of even a small component in the multistage sequence of transforming raw materials into human nutrition leads to failure of the entire task.

MIT economist Michael Kremer has shown that when corporations of many types are confronted with such sequential tasks, they put their highest-skilled staff at the final stages of production. Otherwise the companies risk losing all the value they have added to their raw materials through the production sequence.

Who performs the final stages of production in today’s modern food system? That would be us: frenzied, multitasking, money- and time-constrained consumers. At the end of a typical day, we’re often juggling myriad demands as we try to produce a nutritious, delicious meal for our households.

Unfortunately, sprawling modern food systems are not managed like a single integrated firm that’s focused on maximizing profits. And consumers are not the highly skilled heavy hitters that Kremer envisioned to manage the final stage of the complex food system. It’s not surprising that failure – here, wasting food – often is the result.

Indeed, out of everyone employed across the fragmented U.S. food system, consumers may have the least professional training in handling and preparing food. Adding to the mayhem, firms may not always want to help consumers get the most out of food purchases. That could reduce their sales – and if food that’s been stored longer degrades and becomes less appetizing or safe, producers’ reputations could suffer.

Three paths to squash the squandering

What options exist for reducing food waste in the kitchen? Here are several approaches.

• Build consumer skills.

This could start with students, perhaps through reinvesting in family and consumer science courses – the modern, expanded realm of old-school home economics classes. Or schools could insert food-related modules into existing classes. Biology students could learn why mold forms, and math students could calculate how to expand or reduce recipes.

Outside of school, there are expanding self-education opportunities available online or via clever gamified experiences like Hellman’s Fridge Night Mission, an app that challenges and coaches users to get one more meal a week out of their fridges, freezers and pantries. Yes, it may involve adding some mayo.

Recent studies have found that when people had the opportunity to brush up on their kitchen management skills early in the COVID-19 pandemic, food waste declined. However, as consumers returned to busy pre-COVID schedules and routines such as eating out, wastage rebounded.

• Make home meal preparation easier.

Enter the meal kit, which provides the exact quantity of ingredients needed. One recent study showed that compared to traditional home-cooked meals, wasted food declined by 38% for meals prepared from kits.

Meal kits generate increased packaging waste, but this additional impact may be offset by reduced food waste. Net environmental benefits may be case specific, and warrant more study.

• Heighten the consequences for wasting food.

South Korea has begun implementing taxes on food wasted in homes by requiring people to dispose of it in special costly bags or, for apartment dwellers, through pay-as-you-go kiosks.

A recent analysis suggests that a small tax of 6 cents per kilogram – which, translated for a typical U.S. household, would total about $12 yearly – yielded a nearly 20% reduction in waste among the affected households. The tax also spurred households to spend 5% more time, or about an hour more per week, preparing meals, but the changes that people made reduced their yearly grocery bills by about $170.

No silver bullets

Each of these paths is promising, but there is no single solution to this problem. Not all consumers will seek out or encounter opportunities to improve their food-handling skills. Meal kits introduce logistical issues of their own and could be too expensive for some households. And few U.S. cities may be willing or able to develop systems for tracking and taxing wasted food.

As the National Academies of Science, Engineering and Medicine concluded in a 2020 report, there’s a need for many solutions to address food waste’s large contribution to global climate change and worldwide nutritional shortfalls. Both the United Nations and the U.S. National Science Foundation are funding efforts to track and measure food waste. I expect that this work will help us understand waste patterns more clearly and find effective ways to squelch the squander sequence.

Brian E. Roe, Professor of Agricultural, Environmental, and Development Economics, The Ohio State University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

The International Space Station is no longer the only place where humans can live in orbit.

On Nov. 29, 2022, the Shenzhou 15 mission launched from China’s Gobi Desert carrying three taikonauts – the Chinese word for astronauts. Six hours later, they reached their destination, China’s recently completed space station, called Tiangong, which means “heavenly palace” in Mandarin. The three taikonauts replaced the existing crew that helped wrap up construction. With this successful mission, China has become just the third nation to operate a permanent space station.

China’s space station is an achievement that solidifies the country’s position alongside the U.S. and Russia as one of the world’s top three space powers. As scholars of space law and space policy who lead the Indiana University Ostrom Workshop’s Space Governance Program, we have been following the development of the Chinese space station with interest.

Unlike the collaborative, U.S.-led International Space Station, Tiangong is entirely built and run by China. The successful opening of the station is the beginning of some exciting science. But the station also highlights the country’s policy of self-reliance and is an important step for China toward achieving larger space ambitions among a changing landscape of power dynamics in space.

Capabilities of a Chinese station

The Tiangong space station is the culmination of three decades of work on the Chinese manned space program. The station is 180 feet (55 meters) long and is comprised of three modules that were launched separately and connected in space. These include one core module where a maximum of six taikonauts can live and two experiment modules for a total of 3,884 cubic feet (110 cubic meters) of space, about one-fifth the size of the International Space Station. The station also has an external robotic arm, which can support activities and experiments outside the station, and three docking ports for resupply vehicles and manned spacecraft.

Like China’s aircraft carriers and other spacecraft, Tiangong is based on a Soviet-era design – it is pretty much a copy of the Soviet Mir space station from the 1980s. But the Tiangong station has been heavily modernized and improved.

The Chinese space station is slated to stay in orbit for 15 years, with plans to send two six-month crewed missions and two cargo missions to it annually. The science experiments have already begun, with a planned study involving monkey reproduction commencing in the station’s biological test cabinets. Whether the monkeys will cooperate is an entirely different matter.

Science and a steppingstone

The main function of the Tiangong station is to perform research on life in space. There is a particular focus on learning about the growth and development of different types of plants, animals and microorganisms, and there are more than 1,000 experiments planned for the next 10 years.

Tiangong is strictly Chinese made and managed, but China has an open invitation for other nations to collaborate on experiments aboard Tiangong. So far, nine projects from 17 countries have been selected.

Although the new station is small compared to the 16 modules of the International Space Station, Tiangong and the science done aboard will help support China’s future space missions. In December 2023, China is planning to launch a new space telescope called Xuntian. This telescope will map stars and supermassive black holes among other projects with a resolution about the same as the Hubble Space Telescope but with a wider view. The telescope will periodically dock with the station for maintenance.

China also has plans to launch multiple missions to Mars and nearby comets and asteroids with the goal of bringing samples back to Earth. And perhaps most notably, China has announced plans to build a joint Moon base with Russia – though no timeline for this mission has been set.

Astropolitics

A new era in space is unfolding. The Tiangong station is beginning its life just as the International Space Station, after more than 30 years in orbit, is set to be decommissioned by 2030.

The International Space Station is the classic example of collaborative ideals in space – even at the height of the Cold War, the U.S. and the Soviet Union came together to develop and launch the beginnings of the space station in the early 1990s. By comparison, China and the U.S. have not been so jovial in their orbital dealings.

In the 1990s, when China was still launching U.S. satellites into orbit, concerns emerged that China was accidentally acquiring – or stealing – U.S. technology. These concern in part led to the Wolf Amendment, passed by Congress in 2011, which prohibits NASA from collaborating with China in any capacity. China’s space program was not mature enough to be part of the construction of the International Space Station in the 1990s and early 2000s. By the time China had the ability to contribute to the International Space Station, the Wolf Amendment prevented it from doing so.

It remains to be seen how the map of space collaboration will change in the coming years. The U.S.-led Artemis Program that aims to build a self-sustaining habitat on the Moon is open to all nations, and 19 countries have joined as partners so far. China has also recently opened its joint Moon mission with Russia to other nations. This was partly driven by cooling Chinese-Russian relations but also due to the fact that because of the war in Ukraine, Sweden, France and the European Space Agency canceled planned missions with Russia.

As tensions on Earth rise between China, Russia and the West, and some of that jockeying spills over into space, it remains to be seen how the decommissioning of the International Space Station and operation of the Tiangong station will influence the China-U.S. relationship.

An event like the famous handshake between U.S. astronauts and Russian cosmonauts while orbiting Earth in 1975 is a long way off, but collaboration between the U.S. and China could do much to cool tensions on and above the Earth.

Eytan Tepper, Visiting Assistant Professor of Space Governance, Indiana University and Scott Shackelford, Professor of Business Law and Ethics, Indiana University

This article is republished from The Conversation under a Creative Commons license. Read the original article.