<div id="readability-page-1">A cold weather warning was issued as Hong Kong ushered in 2026, with the temperature dropping to 12 degrees Celsius (54 degrees Fahrenheit) overnight. There was a chill in the air and windy conditions in the days that followed as a cold front moved through.\nWhile winter in the city is projected to be normal, day-to-day fluctuations mean that residents can expect the occasional cold snap for the rest of the season.\nFor many people, less sunlight, lower temperatures and decreased humidity in the cooler months can spell a decline in mental and emotional well-being, sometimes referred to as SAD, or seasonal affective disorder.\nSAD explained\nAmerican psychiatrist Norman Rosenthal coined the term SAD in 1984. A subtype of depression, SAD typically starts in the autumn and winter, when the daylight hours are shorter.\n\nRosenthal and colleagues at the US National Institute of Mental Health theorised that less sunlight could throw the internal body clock, known as the circadian rhythm, off balance, lowering levels of serotonin, a chemical messenger that helps regulate mood, sleep, digestion and other functions.\nSigns of SAD\nIn his 2005 book, Winter Blues: Everything You Need to Know to Beat Seasonal Affective Disorder, Rosenthal describes how people with SAD experience low mood, fatigue, difficulty concentrating, increased sleep and carbohydrate cravings.\nBesides that, inclement weather may make us behave in ways that maintain a low mood, adds Bea Smith, a psychotherapist at Maple Tree Counselling in Hong Kong. We may exercise less, spend less time outdoors and socialise less – all “natural antidepressant” activities.\nIn spring and summer, SAD symptoms tend to dissipate naturally.\n\nThese symptoms overlap with those of major depression, but there are some differences, Smith says.\n“For example, with SAD, there’s a strong desire to ‘hibernate’ – cancel plans and stay home – which would improve as the season changes. With the change in season, people lose their motivation to socialise and engage in the activities that they usually enjoy.\n“When someone’s got major depression but doesn’t have SAD, this loss of interest and social withdrawal would be longer lasting and not specifically triggered by the environment and weather.”\nRisk factors for SAD\nAnyone can experience SAD, but certain factors increase vulnerability.\n“It is three to four times more common in women, possibly due to fluctuating hormonal levels, although men are more likely to have severe symptoms, with a higher risk of self-harm and attempting suicide,” Smith says.\nThere is not enough research into the gender difference to make conclusions about the reasons behind it, she says, but “men may be less likely to report SAD or seek treatment for it”.\n\nAge is another factor: the onset of SAD usually occurs in young adulthood, around 18 to 30 years old, although it can develop later.\nSAD is also more common in places with drastic seasonal light changes or frequent cloudy weather, Smith says.\nOther risk factors include having a family history of SAD or other depressive disorders, or having a pre-existing condition affecting mood, such as bipolar disorder, she adds.\nSome people are born with a hypersensitivity to light changes or have genes that affect their circadian rhythm, serotonin or melatonin systems. This would increase the impact of a reduction in sunlight.\nShe adds that going through a difficult life transition and grieving a loss can add to the biological burden of the change in season, depleting one’s coping resources and making SAD symptoms more pronounced.\nDon’t be SAD: tips to overcome symptoms\n1. Get moving\nEngaging in physical activity outside is ideal, but exercising indoors is as helpful, says Jessica Lau, a counselling psychologist at the Integrated Medicine Institute in Hong Kong.\n“Even short bouts of activity can trigger the release of endorphins, your body’s natural mood lifters.”\n\n2. Stay connected\nIf the weather is preventing you from catching up with friends in person, Lau recommends staying in touch through calls or virtual meetings.\n3. Eat a balanced diet\nWhat we eat can influence our emotional well-being. Lau recommends including plenty of fruits, vegetables, whole grains, lean proteins and omega-3 fatty acids, which are found in fatty fish, flax seeds, walnuts and edamame beans.\n“Dark chocolate, bananas, nuts and fatty fish, in particular, are known for their mood-boosting properties,” she notes.\n\n4. Adjust your environment\nSmith says to differentiate the parts of your home that are cosy and comforting with a brighter-lit space for engaging in hobbies – using warm, energising lights, for example.\n“Decorate your sleeping and living areas with items that bring you joy and uplift you. Using a calendar to plan activities and count down the days until a fun event or the end of the season can also be motivating,” she adds.\n5. Change your thinking\nReminding yourself of positive experiences in previous winters can help you develop a more balanced perception of this season, especially if you believe that the cold season is always miserable, Lau says.\n6. Meditate using imagery\nMindful activities, like yoga and meditation, can help you relax and feel more grounded. Lau suggests meditating while picturing a sunrise and imagining the warmth from the sun enveloping your body.\n\n7. Establish a routine\nMaintain a consistent daily routine to create structure and predictability, Lau says.\nThis will not only give you a sense of control and stability, but it also creates space for healthy habits such as exercise and quality sleep.\n8. Be kind to yourself\nIt is OK to feel and go slower during this time, Smith points out. It is not about having summer-level energy, but rather, building a gentle, steady momentum. One small, kind act for yourself each day will add up over time.\n9. Try bright light therapy\nRosenthal pioneered bright light therapy as a main treatment for SAD. Studies show that light exposure can improve SAD sufferers’ mood and reduce their depressive symptoms.\n\nToday, aged 75, Rosenthal is a professor of psychiatry at Georgetown University School of Medicine in Washington and runs a private practice. In recent media reports, he says his own home is filled with light boxes.\nThis is the first-line, gold standard treatment for SAD, says Smith.\nSit in front of a special light box (10,000 lux) for about 20 to 30 minutes every morning. The box mimics natural outdoor light, suppressing melatonin production and increasing serotonin, essentially tricking your brain into thinking it is a brighter, longer day, Smith says. Use an approved medical device and follow timing guidelines – consult a professional to get started.\nUsing dawn simulators may also help. Smith says that these alarm clocks gradually increase the brightness in your room before you wake up, simulating a natural sunrise and providing a gentler transition to daytime than a jarring sound in the dark.\nExposure to natural light, such as taking morning walks or sitting by a window during the day, may also boost serotonin levels in the brain, lifting our moods and helping us feel calm and focused.\n\nWhat is reverse SAD?\nThe opposite of winter SAD, reverse SAD (also known as summer SAD), occurs during the spring and summer months. Due to Hong Kong’s location in a subtropical latitude, summer SAD is said to be more prevalent than its cold weather counterpart.\nExtreme heat and humidity can cause physical discomfort, dehydration and disturbed sleep – especially on hot nights. These factors may trigger symptoms such as depressed mood, anxiety and agitation, insomnia, and decreased appetite.\nResearch focusing on seasonal variation in mood among a Chinese study group found that summer SAD symptoms were reported at a higher frequency than winter SAD ones.\nA 2018 study in the International Journal of Environmental Research and Public Health found a positive association between rising ambient temperatures and an increase in mental disorder hospital admissions in Hong Kong, particularly among older people.\n\nWhile there have not been many studies on the treatment of summer SAD, cooling your environment and taking cold showers may alleviate some of the discomfort.\nIn 2023, Rosenthal released Defeating SAD (Seasonal Affective Disorder): A Guide to Health and Happiness Through All Seasons. It discusses both winter and summer varieties of SAD, and the less severe yet bothersome “winter blues”.\nIt has strategies and techniques for defeating them, including psychotherapy and medication, diet and exercise advice, and meditation.\nLike what you read? Follow SCMP Lifestyle on Facebook, X and Instagram. You can also sign up for our eNewsletter here.\n</div>

<p>A cold weather warning was issued in Hong Kong as temperatures dropped to 12°C. This winter, residents may experience seasonal affective disorder (SAD), a subtype of depression linked to reduced sunlight. Symptoms include low mood, fatigue, and social withdrawal. Risk factors include gender, age, and family history. To combat SAD, experts recommend physical activity, staying connected, maintaining a balanced diet, adjusting home environments, and changing negative thought patterns.</p>

What is SAD? Why seasonal affective disorder makes you feel down, and how to combat it